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How to_do_Preventive_ Maintenance_Condenser_Heat Exchanger_صيانة المبادل الحرارى
WEBVTT Kind: captions Language: en
00:00:00.150 [Music] 00:00:09.64000:00:09.650 by now you have a good idea of what heat 00:00:12.29000:00:12.300 exchangers are and how they work and you 00:00:14.33000:00:14.340 know some of the kinds of things that 00:00:16.22000:00:16.230 can go wrong with heat exchangers in 00:00:17.81000:00:17.820 this unit we're going to find out what 00:00:20.42000:00:20.430 to do to cure these problems we'll also 00:00:22.70000:00:22.710 take a look at what's done to keep heat 00:00:24.23000:00:24.240 exchangers in the plant working 00:00:25.75900:00:25.769 efficiently we'll be seeing routine 00:00:28.27900:00:28.289 maintenance typical repair jobs and 00:00:30.29000:00:30.300 online temporary fixes what we're going 00:00:33.65000:00:33.660 to be doing in this segment is give an 00:00:35.45000:00:35.460 overview of the subject so you'll have a 00:00:36.97900:00:36.989 broad picture of what your job on heat 00:00:39.17000:00:39.180 exchangers is going to be we'll also 00:00:42.17000:00:42.180 look into a couple of very simple 00:00:43.54900:00:43.559 procedures in more detail before going 00:00:45.83000:00:45.840 on to a close look at major tasks now 00:00:49.61000:00:49.620 what a heat exchanger is out of service 00:00:51.38000:00:51.390 for routine scheduled maintenance 00:00:53.33000:00:53.340 the first thing needed is a thorough 00:00:55.97000:00:55.980 cleaning with surface heat exchangers 00:00:59.38900:00:59.399 condensers and other shell and tube 00:01:01.09900:01:01.109 units this usually means cleaning out 00:01:03.04900:01:03.059 the water boxes or headers and clearing 00:01:04.93900:01:04.949 the tubes of any blockage cleaning an 00:01:07.52000:01:07.530 inspection is also done with direct 00:01:09.50000:01:09.510 contact heat exchangers with direct 00:01:12.41000:01:12.420 contact heat exchangers you're usually 00:01:14.30000:01:14.310 looking for corrosion and scale and some 00:01:16.78900:01:16.799 of the problems they'll cause this might 00:01:19.10000:01:19.110 be blockage of inlet nozzles or loose 00:01:21.08000:01:21.090 scale might get in to clean feed water 00:01:22.78900:01:22.799 as it leaves the heat exchanger 00:01:24.91000:01:24.920 maintenance on direct contact heaters is 00:01:27.49900:01:27.509 usually nothing but re welding or 00:01:29.27000:01:29.280 replacing trays and trays supports since 00:01:32.03000:01:32.040 this is about all you'll ever need to 00:01:33.38000:01:33.390 worry about with direct contact heat 00:01:35.27000:01:35.280 exchangers will limit our discussion in 00:01:37.55000:01:37.560 this unit to maintenance of surface heat 00:01:39.64900:01:39.659 exchangers cleaning out condensers often 00:01:43.28000:01:43.290 involves scraping tube sheets and raking 00:01:45.38000:01:45.390 accumulated crud out of water boxes 00:01:47.49900:01:47.509 headers and large shell and tube units 00:01:49.88000:01:49.890 are usually cleaner in smaller units 00:01:52.37000:01:52.380 it's just a matter of disassembling them 00:01:54.13900:01:54.149 for cleaning your cleaning methods will 00:01:56.56900:01:56.579 depend on what's going through the heat 00:01:58.34000:01:58.350 exchanger and the kinds of impurities in 00:02:00.83000:02:00.840 the fluids cleaning the inside of tubes 00:02:03.83000:02:03.840 can be done several ways on bigger units 00:02:06.70900:02:06.719 if the build-up is moderate and easy to 00:02:08.71900:02:08.729 remove such as slime from algae and 00:02:10.82000:02:10.830 other water growth a stream of water 00:02:12.89000:02:12.900 under high 00:02:13.76000:02:13.770 we'll do the trick you use a water gun 00:02:16.43000:02:16.440 which is just held in the end of each 00:02:18.68000:02:18.690 tube pulling the trigger shoots water 00:02:21.02000:02:21.030 through the tube 00:02:21.92000:02:21.930 now sometimes compressed air is mixed 00:02:24.35000:02:24.360 with the water to churn the muck and 00:02:25.85000:02:25.860 sludge off the walls of the tubes 00:02:28.24000:02:28.250 now if deposits are really hard to 00:02:30.50000:02:30.510 remove the same gun is used to shoot the 00:02:32.75000:02:32.760 tubes with rubber plugs wire brushes or 00:02:38.18000:02:38.190 metal scrapers sometimes called bullets 00:02:41.92000:02:41.930 the one you choose depends on what you 00:02:44.54000:02:44.550 trying to get out and that depends on 00:02:46.55000:02:46.560 what's going through the heat exchanger 00:02:49.00000:02:49.010 another way of cleaning tubes is rotting 00:02:51.62000:02:51.630 it's the elbow grease version of 00:02:53.66000:02:53.670 shooting tubes and is practical on small 00:02:55.94000:02:55.950 heat exchangers like a small oil cooler 00:02:57.83000:02:57.840 and there are also devices like plumbers 00:03:00.38000:03:00.390 snakes use to clean drains and sewers 00:03:02.21000:03:02.220 they remove the toughest stuff with a 00:03:04.64000:03:04.650 rotating scraper on a flexible cable in 00:03:07.97000:03:07.980 large heat exchangers tube bundles can 00:03:10.37000:03:10.380 be pulled out so the outside of tubes 00:03:12.65000:03:12.660 can be cleaned corrosion scale and 00:03:15.59000:03:15.600 deposits can be brushed off with wire 00:03:17.24000:03:17.250 brushes once the heat exchanger is 00:03:20.57000:03:20.580 cleaned out a thorough and careful 00:03:22.58000:03:22.590 inspection is in order to find any leaks 00:03:24.62000:03:24.630 that exist while the system was running 00:03:27.23000:03:27.240 there may have been no evidence of 00:03:28.97000:03:28.980 leakage problems regardless it's really 00:03:32.18000:03:32.190 important to make your inspection as 00:03:33.65000:03:33.660 thorough as possible 00:03:34.94000:03:34.950 the more careful you make your 00:03:36.56000:03:36.570 inspection but less likely it is that a 00:03:38.84000:03:38.850 problem will crop up before the next 00:03:40.22000:03:40.230 scheduled maintenance a number of things 00:03:43.28000:03:43.290 go into this detailed inspection to 00:03:45.32000:03:45.330 check for leaks and a surface heat 00:03:46.76000:03:46.770 exchanger you may use a dye check or you 00:03:49.40000:03:49.410 may perform a vacuum test now these 00:03:51.77000:03:51.780 might be done while the component is in 00:03:53.69000:03:53.700 service or they might be performed while 00:03:55.88000:03:55.890 the unit's down after it's been cleaned 00:03:57.94900:03:57.959 after cleaning a visual inspection is 00:04:01.19000:04:01.200 done for evidence of corrosion cracking 00:04:03.86000:04:03.870 or to look for any more blockage while 00:04:07.97000:04:07.980 some heat exchanges are in service a 00:04:09.83000:04:09.840 telltale dye can be added to the water 00:04:11.78000:04:11.790 going into them to look for any leaks 00:04:13.36000:04:13.370 this is usually a fluorescent dye that 00:04:16.01000:04:16.020 glows when it's exposed to blacklight a 00:04:18.89000:04:18.900 source of ultraviolet light any leakage 00:04:21.59000:04:21.600 will show up where the dye comes through 00:04:23.33000:04:23.340 on condensers and other heat exchangers 00:04:26.78000:04:26.790 which are 00:04:27.26000:04:27.270 under a vacuum a vacuum check can be 00:04:30.05000:04:30.060 used to look for leaks it involves 00:04:32.45000:04:32.460 placing sheets of thin plastic wrap on 00:04:34.79000:04:34.800 the tube sheets to cover both ends of 00:04:36.86000:04:36.870 the tubes this is done while a vacuum is 00:04:40.46000:04:40.470 drawn on the shell of the component now 00:04:42.92000:04:42.930 the plastic wrap is just like the stuff 00:04:45.11000:04:45.120 that you use in your kitchen and it 00:04:47.11900:04:47.129 sticks to the tube sheets as well as to 00:04:49.18900:04:49.199 itself now if there's a leak in the tube 00:04:51.80000:04:51.810 the plastic wrap will be sucked into 00:04:53.60000:04:53.610 that tube that's a dead giveaway 00:04:56.29000:04:56.300 after a condenser or shell and tube heat 00:04:58.61000:04:58.620 exchangers clean and a good thorough 00:05:00.83000:05:00.840 inspections been made any leaks that 00:05:03.11000:05:03.120 have been found need to be taken care of 00:05:04.64000:05:04.650 now generally you plug a leaking to but 00:05:07.43000:05:07.440 each end to keep fluid from going 00:05:08.83900:05:08.849 through normally you don't try to stop 00:05:10.96900:05:10.979 the leak itself later on we'll be seeing 00:05:13.67000:05:13.680 in detail how plugging is done sometimes 00:05:17.12000:05:17.130 you may find a leak around where a tube 00:05:19.21900:05:19.229 goes through the tube sheet you might 00:05:21.95000:05:21.960 have to plug the tube or you may be able 00:05:24.49900:05:24.509 to weld the end of the tube to the tube 00:05:26.20900:05:26.219 sheet it's possible you may have to do 00:05:28.70000:05:28.710 both tube replacement is often a job 00:05:32.02900:05:32.039 that's farmed out it may be farmed out 00:05:34.10000:05:34.110 to a reef itter or back to the 00:05:35.71900:05:35.729 manufacturer of the unit sometimes 00:05:37.70000:05:37.710 though you may do such a job in house 00:05:40.08900:05:40.099 tube replacement is almost always done 00:05:42.49900:05:42.509 in wholesale Lots when so many tubes 00:05:45.17000:05:45.180 have been plugged that the efficiency of 00:05:46.58000:05:46.590 the heat exchanger is affected tubes are 00:05:49.73000:05:49.740 usually set into tube sheets in one of 00:05:51.76900:05:51.779 two ways 00:05:52.24000:05:52.250 one method is by rolling which is a way 00:05:55.27900:05:55.289 of expanding the ends of the tubes into 00:05:57.17000:05:57.180 corrugated openings in the tube sheet 00:05:59.14000:05:59.150 the other method is to weld the tubes 00:06:01.99900:06:02.009 into the tube sheet openings whichever 00:06:05.48000:06:05.490 way the tubes are set into the tube 00:06:06.95000:06:06.960 sheet any that have to be replaced must 00:06:09.62000:06:09.630 be cut away very carefully after 00:06:12.08000:06:12.090 removing the old tube on the you tube is 00:06:14.05900:06:14.069 set into place and fixed to the tube 00:06:15.74000:06:15.750 sheet the same way as the original tube 00:06:18.45900:06:18.469 will be studying these things in more 00:06:20.62900:06:20.639 detail further on will be going into 00:06:22.61000:06:22.620 inspection cleaning and repair jobs on 00:06:25.07000:06:25.080 both large and small heat exchangers and 00:06:27.20000:06:27.210 we'll take a look at some of the 00:06:28.82000:06:28.830 equipment you'll be using on the job to 00:06:30.68000:06:30.690 see how it's done 00:06:32.26000:06:32.270 before we go on let me mention the 00:06:35.02900:06:35.039 importance of sacrificial anodes 00:06:37.70000:06:37.710 they aren't used in all heat exchangers 00:06:39.83000:06:39.840 but attention has to be paid to them 00:06:41.78000:06:41.790 where they are used there really isn't 00:06:44.90000:06:44.910 much you can say about sacrificial 00:06:46.73000:06:46.740 anodes except that they're a little bit 00:06:47.90000:06:47.910 heavy and the details of their 00:06:49.64000:06:49.650 maintenance are so simple that we won't 00:06:50.99000:06:51.000 spend a lot of time on the subject we've 00:06:53.45000:06:53.460 already talked about them and discuss 00:06:54.80000:06:54.810 the way they work they're called 00:06:57.68000:06:57.690 sacrificial because they are eaten away 00:06:59.93000:06:59.940 by corrosion rather than the metals of 00:07:02.15000:07:02.160 the heat exchanger when they're worn 00:07:04.25000:07:04.260 down so far they have to be replaced 00:07:06.28000:07:06.290 just when is usually a matter of 00:07:08.39000:07:08.400 judgment but one rule of thumb is to 00:07:11.27000:07:11.280 replace them when they're more than 50% 00:07:13.19000:07:13.200 eaten away or when they are in danger of 00:07:16.19000:07:16.200 coming loose from their mountings 00:07:18.28000:07:18.290 replacement is a straightforward job of 00:07:20.60000:07:20.610 just bolting a new one in the place of 00:07:23.00000:07:23.010 the old one and you're done after all 00:07:27.86000:07:27.870 the rest of your maintenance tasks are 00:07:29.39000:07:29.400 completed it's time to clean up tools 00:07:31.61000:07:31.620 and equipment when you've made sure that 00:07:34.01000:07:34.020 nothing's been overlooked the unit can 00:07:36.08000:07:36.090 be closed up it might be tested before 00:07:39.53000:07:39.540 it's put back into service 00:07:40.73000:07:40.740 this might include flow testing pressure 00:07:43.79000:07:43.800 or vacuum testing leak tests and so 00:07:46.34000:07:46.350 forth it has to pass any tests that are 00:07:49.58000:07:49.590 performed before the component is ready 00:07:51.14000:07:51.150 to go back online routine maintenance 00:07:54.50000:07:54.510 tasks are usually pretty simple about as 00:07:57.35000:07:57.360 simple as heat exchangers themselves 00:07:59.15000:07:59.160 still each job has to be done with care 00:08:02.24000:08:02.250 and thoroughly completed then you can 00:08:05.45000:08:05.460 expect everything to work just fine when 00:08:07.31000:08:07.320 the system's put back into service now 00:08:10.46000:08:10.470 before we go on further pause to study 00:08:12.92000:08:12.930 the first section of your text and 00:08:14.42000:08:14.430 answer the questions get your instructor 00:08:16.76000:08:16.770 to clear up any questions you may have 00:08:18.16000:08:18.170 when we come back we're going to see 00:08:20.84000:08:20.850 what any big heat exchanger job begins 00:08:23.03000:08:23.040 with 00:08:23.84000:08:23.85000:08:33.67000:08:33.680 so far we've seen that heat exchangers 00:08:36.56000:08:36.570 are really pretty simple devices it 00:08:39.08000:08:39.090 doesn't exactly take the skill of a 00:08:40.55000:08:40.560 surgeon to operate on a heat exchanger 00:08:42.95000:08:42.960 and the tools you need to work on a heat 00:08:45.14000:08:45.150 exchanger aren't as varied and complex 00:08:47.12000:08:47.130 as those you'd find in the operating 00:08:48.56000:08:48.570 room either nevertheless it's important 00:08:51.38000:08:51.390 to give thought and care to any job you 00:08:53.36000:08:53.370 do the things you do to prepare for the 00:08:55.67000:08:55.680 job call for thought about what you'll 00:08:57.44000:08:57.450 be doing and the precautions necessary 00:08:59.48000:08:59.490 to ensure doing the job safely deserve 00:09:02.18000:09:02.190 consideration - now when we prepare for 00:09:05.63000:09:05.640 any maintenance job we've got to select 00:09:08.00000:09:08.010 the tools necessary to do the job these 00:09:10.82000:09:10.830 tools include safety items as well as 00:09:13.22000:09:13.230 stuff for mechanical work part of our 00:09:15.98000:09:15.990 preparations also include procedures we 00:09:18.68000:09:18.690 have to follow - ready the equipment to 00:09:20.72000:09:20.730 be worked on these practices include 00:09:23.54000:09:23.550 shutting down the system and tagging 00:09:25.52000:09:25.530 equipment so it won't be operated while 00:09:27.77000:09:27.780 you're doing work now when a work order 00:09:30.71000:09:30.720 comes down for a maintenance job the 00:09:33.29000:09:33.300 first thing to do is check out the 00:09:35.12000:09:35.130 equipment you'll be working on you 00:09:37.49000:09:37.500 should also look at any manufacturers 00:09:39.53000:09:39.540 manuals or spec sheets on the equipment 00:09:41.63000:09:41.640 this way you can figure out exactly what 00:09:44.75000:09:44.760 you'll need to do the job if you know 00:09:47.39000:09:47.400 what you'll be working on and if you 00:09:49.40000:09:49.410 know what the task is then you can 00:09:51.89000:09:51.900 decide what tools and equipment you need 00:09:54.82000:09:54.830 let's see what this takes Mel here just 00:09:59.03000:09:59.040 got a work order to open and inspect the 00:10:01.13000:10:01.140 waterboxxes of the main condenser on 00:10:03.32000:10:03.330 turbine unit number 12 00:10:05.18000:10:05.190 now maintenance practices vary from 00:10:07.97000:10:07.980 place to place in Mel's plant the 00:10:11.15000:10:11.160 operations people are responsible for 00:10:13.31000:10:13.320 shutting down the Associated systems and 00:10:15.53000:10:15.540 draining the condenser in some plants 00:10:18.32000:10:18.330 Mel might do this part of the 00:10:20.24000:10:20.250 preparation himself equipment tags are 00:10:24.11000:10:24.120 placed on all valves and controls to be 00:10:26.39000:10:26.400 sure they're not operated this will 00:10:29.03000:10:29.040 prevent unpleasant surprises while the 00:10:31.10000:10:31.110 jobs going on while he's at it 00:10:33.92000:10:33.930 Mel checks the size of the hardware so 00:10:36.35000:10:36.360 he'll have the right sized wrenches to 00:10:38.27000:10:38.280 open the condenser up back at the tool 00:10:41.36000:10:41.370 room it's just a matter of checking out 00:10:43.13000:10:43.140 the right tools and equipment 00:10:44.90000:10:44.910 and making sure that nothing's 00:10:46.52000:10:46.530 overlooked and while we're at it how 00:10:49.04000:10:49.050 about looking over the equipment to make 00:10:50.84000:10:50.850 sure it's okay 00:10:51.86000:10:51.870 a visual inspection of tools and 00:10:54.14000:10:54.150 equipment can save a trip back to the 00:10:56.24000:10:56.250 tool room or possibly might save a trip 00:10:58.85000:10:58.860 to the doctor let's take a look at the 00:11:01.88000:11:01.890 equipment needs for this job since Mel 00:11:05.27000:11:05.280 or his coworker will be working in a wet 00:11:07.58000:11:07.590 confined area he chooses special low 00:11:10.61000:11:10.620 voltage safety lighting to protect 00:11:12.62000:11:12.630 against a shock hazard they'll need an 00:11:15.29000:11:15.300 impact wrench and a large socket to 00:11:17.51000:11:17.520 loosen the retaining nuts on the 00:11:19.13000:11:19.140 waterboxx doors and it would be a good 00:11:21.86000:11:21.870 idea to take a crowbar along just in 00:11:24.17000:11:24.180 case the swivel studs are really tight a 00:11:26.83000:11:26.840 rain suit and boots will help keep them 00:11:29.78000:11:29.790 dry inside the water box especially if 00:11:32.54000:11:32.550 they have to do any cleaning of the 00:11:34.13000:11:34.140 water box or the tubes now if any 00:11:37.73000:11:37.740 chemical corrosion inhibitors were used 00:11:39.68000:11:39.690 in this system very special precautions 00:11:42.56000:11:42.570 would be needed to protect the eyes and 00:11:44.48000:11:44.490 the skin many of these are chromate 00:11:47.15000:11:47.160 solutions and they're especially 00:11:48.65000:11:48.660 hazardous if you have no protection 00:11:51.31000:11:51.320 sometimes breathing protection is even 00:11:53.75000:11:53.760 needed where these chemicals are used 00:11:55.57000:11:55.580 they'll need an air quality check a 00:11:58.49000:11:58.500 sniff tester like this one not only 00:12:01.55000:12:01.560 tells if there's enough oxygen to 00:12:03.44000:12:03.450 breathe inside the confined workspace 00:12:05.12000:12:05.130 but also signals if there are any 00:12:07.49000:12:07.500 explosive gases present in Mel's plant 00:12:11.45000:12:11.460 the instrumentation people are 00:12:13.40000:12:13.410 responsible for doing this check but in 00:12:15.89000:12:15.900 a lot of places mell would do it for 00:12:17.93000:12:17.940 himself 00:12:19.39000:12:19.400 now since the cooling water and this 00:12:21.68000:12:21.690 plants condensers comes in from the 00:12:23.54000:12:23.550 river nearby there's likely to be a lot 00:12:25.49000:12:25.500 of muck inside so in order to do a 00:12:28.04000:12:28.050 thorough and complete inspection in the 00:12:30.05000:12:30.060 condenser Mel's helper is going to need 00:12:32.72000:12:32.730 to clean accumulated junk out of the 00:12:34.67000:12:34.680 water box and off the face of the tube 00:12:36.41000:12:36.420 sheets first for this he'll need pics 00:12:39.08000:12:39.090 and scrapers and a rake will make it 00:12:41.00000:12:41.010 easier to get the big stuff a shovel and 00:12:43.49000:12:43.500 a container to pass the crud out to be 00:12:45.38000:12:45.390 dumped round out what they'll need for 00:12:47.09000:12:47.100 this part of the job because they're 00:12:50.09000:12:50.100 sure of having to clean out the tubes 00:12:52.01000:12:52.020 they'll be certain to check out a 00:12:53.87000:12:53.880 high-pressure water gun and maybe a 00:12:55.82000:12:55.830 bunch of scrapers brushes or squeegees 00:12:58.16000:12:58.170 to shoot 00:12:58.77000:12:58.780 tubes with this will come later in this 00:13:00.93000:13:00.940 job and now it's down to the job when 00:13:05.19000:13:05.200 our worker was looking over the unit 00:13:06.72000:13:06.730 earlier he made sure the water boxes 00:13:09.12000:13:09.130 were drained and that equipment had been 00:13:10.62000:13:10.630 tagged out so he knows it's safe to open 00:13:12.72000:13:12.730 up the condenser it's been a while since 00:13:15.66000:13:15.670 this units been opened up so the impact 00:13:18.00000:13:18.010 wrench will make it a lot easier to open 00:13:19.74000:13:19.750 it than if they had to use hand tools 00:13:21.62000:13:21.630 the large nuts are backed off only 00:13:24.36000:13:24.370 enough to allow the studs to be swiveled 00:13:26.52000:13:26.530 out of the way when the last one loose 00:13:28.83000:13:28.840 the door comes open easily after opening 00:13:32.94000:13:32.950 two doors on each side of the water box 00:13:35.28000:13:35.290 the very first thing to do is an air 00:13:38.13000:13:38.140 quality check this is necessary before 00:13:40.77000:13:40.780 you go to work in any kind of confined 00:13:43.32000:13:43.330 area the sniff tester is calibrated for 00:13:46.17000:13:46.180 both readings it'll take after 00:13:48.09000:13:48.100 calibrating the meter a sample of the 00:13:50.49000:13:50.500 atmosphere and the water box is drawn 00:13:52.38000:13:52.390 into the tester through the nozzle at 00:13:54.09000:13:54.100 the end of the hose the meter shows how 00:13:56.58000:13:56.590 much oxygen content is in the air and 00:13:58.44000:13:58.450 any percentage of explosive gases if 00:14:02.79000:14:02.800 either reading falls outside the safe 00:14:05.13000:14:05.140 limits on alarm goes off and the meter 00:14:07.77000:14:07.780 will tell you exactly what's wrong in 00:14:10.16000:14:10.170 this case there's plenty of oxygen 00:14:12.33000:14:12.340 inside and no gases are present to cause 00:14:14.70000:14:14.710 danger if there were the water box would 00:14:17.64000:14:17.650 have to be ventilated or if it were 00:14:20.34000:14:20.350 impossible to ventilate anyone working 00:14:22.53000:14:22.540 inside would have to use a respirator 00:14:25.28000:14:25.290 even though the air inside the water box 00:14:27.78000:14:27.790 is safe this crew has decided to provide 00:14:30.69000:14:30.700 ventilation using this large fan the 00:14:34.05000:14:34.060 fresh plant air will make it more 00:14:35.46000:14:35.470 pleasant to work inside the water box 00:14:38.06000:14:38.070 now this units been shut down for a 00:14:40.35000:14:40.360 couple of days so it's cool enough to 00:14:43.08000:14:43.090 work in without danger of fatigue or 00:14:45.12000:14:45.130 heat exhaustion if it were still hot 00:14:47.61000:14:47.620 they might have to take special 00:14:49.08000:14:49.090 precautions such as extra ventilation 00:14:51.48000:14:51.490 for cooling or even reduce the work 00:14:53.64000:14:53.650 cycle to prevent heat exhaustion from 00:14:55.74000:14:55.750 working in a hot environment of course 00:14:58.50000:14:58.510 our mechanics are observing the two-man 00:15:00.33000:15:00.340 rule - this is a very basic safety rule 00:15:03.39000:15:03.400 for any kind of work in a confined space 00:15:05.30000:15:05.310 there's always one man on the outside 00:15:07.95000:15:07.960 not only to serve as a helper but to 00:15:10.29000:15:10.300 ensure the safety of the worker in 00:15:12.35000:15:12.360 the man can call for help and provide 00:15:15.69000:15:15.700 assistance if the worker inside gets 00:15:17.70000:15:17.710 into any trouble all these preparations 00:15:20.79000:15:20.800 and precautions we've talked about in 00:15:23.19000:15:23.200 this part of the program make the job 00:15:25.26000:15:25.270 easier and safer easier because the 00:15:28.98000:15:28.990 thoughtful planning that goes into 00:15:30.33000:15:30.340 getting ready for the job keeps the 00:15:32.04000:15:32.050 number of steps involved down to a 00:15:33.72000:15:33.730 minimum and safer because the care 00:15:36.96000:15:36.970 that's taken to observe precautions in 00:15:39.18000:15:39.190 doing the job ensure that the worker 00:15:41.52000:15:41.530 doesn't have to deal with unnecessary 00:15:43.29000:15:43.300 dangers on the job in this part we've 00:15:47.40000:15:47.410 looked at preparations such as draining 00:15:49.35000:15:49.360 the condenser and shutting off valves 00:15:51.33000:15:51.340 and pumps in the system choosing tools 00:15:53.49000:15:53.500 and equipment for the job and opening up 00:15:55.65000:15:55.660 the unit we've also talked about safety 00:15:58.17000:15:58.180 precautions like tagging out equipment 00:16:00.12000:16:00.130 special safety lighting air testing and 00:16:02.97000:16:02.980 the two-man rule for working in a 00:16:04.92000:16:04.930 confined space and we've seen all these 00:16:07.59000:16:07.600 preparations and precautions followed 00:16:09.48000:16:09.490 properly up to the point where the 00:16:11.64000:16:11.650 condenser is open and they're ready for 00:16:13.80000:16:13.810 work to begin now all these procedures 00:16:16.56000:16:16.570 also apply to work on large shell and 00:16:19.35000:16:19.360 tube heat exchangers in some cases the 00:16:22.38000:16:22.390 headers will be opened up so the problem 00:16:24.39000:16:24.400 of a confined workspace doesn't exist 00:16:26.57900:16:26.589 but gases can still be present as the 00:16:29.73000:16:29.740 head is coming off we'll be looking 00:16:32.01000:16:32.020 inside a large shell and tube heat 00:16:33.57000:16:33.580 exchanger further on as we follow Mel's 00:16:36.12000:16:36.130 job - before we go on to the actual work 00:16:39.24000:16:39.250 to be done pause now to read through 00:16:41.40000:16:41.410 chapter 2 in your text and answer the 00:16:43.47000:16:43.480 questions your instructor will discuss 00:16:45.90000:16:45.910 any special procedures that are followed 00:16:47.85000:16:47.860 in your plant and can answer any 00:16:49.82900:16:49.839 questions you may have when we get back 00:16:52.32000:16:52.330 we'll follow our workers through their 00:16:54.32900:16:54.339 job cleaning and inspecting the 00:16:55.95000:16:55.960 condenser and we'll also take a look at 00:16:58.35000:16:58.360 some of the same kinds of operations on 00:17:00.27000:17:00.280 large shell and tube heat exchangers 00:17:02.96000:17:02.97000:17:17.72000:17:17.730 as we saw earlier there are basically 00:17:20.34000:17:20.350 just two things that can go wrong with 00:17:22.43900:17:22.449 heat exchangers one of these is blockage 00:17:24.84000:17:24.850 and leakage is the other in this part of 00:17:27.92900:17:27.939 the program we'll take a look at the 00:17:29.58000:17:29.590 first one of these maintenance problems 00:17:31.23000:17:31.240 blockage we'll examine the problem in 00:17:33.89900:17:33.909 two ways first we'll talk about the 00:17:36.00000:17:36.010 various routines you'll be using to 00:17:37.52900:17:37.539 clean large surface heat exchangers and 00:17:39.71000:17:39.720 second will see some automatic methods 00:17:42.50900:17:42.519 of cleaning that are used to slow down a 00:17:44.34000:17:44.350 buildup of the things that stop up a 00:17:46.52900:17:46.539 heat exchanger now depending on what 00:17:49.62000:17:49.630 fluids go through a particular heat 00:17:51.36000:17:51.370 exchanger it's pretty easy to know just 00:17:53.66900:17:53.679 what to expect when you open up a unit 00:17:55.74000:17:55.750 after a long period of service when our 00:17:58.64900:17:58.659 mechanic got the work order to open and 00:18:00.62900:18:00.639 inspect the main condenser on number 12 00:18:02.85000:18:02.860 he knew pretty much what he was going to 00:18:04.62000:18:04.630 find he planned the job accordingly he 00:18:08.54900:18:08.559 chose the necessary cleaning tools as 00:18:10.35000:18:10.360 well as his personal protective gear 00:18:12.52900:18:12.539 once the unit was opened up from the air 00:18:15.06000:18:15.070 quality check told him the air was safe 00:18:16.68000:18:16.690 inside all it took was a quick 00:18:18.65900:18:18.669 inspection to confirm his judgment oh 00:18:20.75900:18:20.769 what a mess oh well it could have been a 00:18:24.12000:18:24.130 lot worse 00:18:24.81000:18:24.820 the unit had been in service for quite a 00:18:26.87900:18:26.889 while and in all that time this was all 00:18:29.46000:18:29.470 that had accumulated inside well the 00:18:32.39900:18:32.409 first thing to do is suit up and go 00:18:33.89900:18:33.909 inside our workers got to be careful of 00:18:36.65900:18:36.669 his footing in that water box the 00:18:38.37000:18:38.380 surface is in there very slippery the 00:18:40.23000:18:40.240 last thing he wants to do is fall and 00:18:41.90900:18:41.919 take a bath in that stuff or hurt 00:18:43.95000:18:43.960 himself scraping the tube sheet and 00:18:47.00900:18:47.019 picking things out of the ends of the 00:18:48.48000:18:48.490 tubes just requires patience to get it 00:18:51.33000:18:51.340 all it really doesn't matter whether he 00:18:54.18000:18:54.190 cleans the tube sheets first or shovels 00:18:56.12900:18:56.139 off the water box it's all got to go but 00:18:58.95000:18:58.960 if the stuff in the water box isn't 00:19:01.23000:19:01.240 downright hazardous it's more practical 00:19:02.94000:19:02.950 to clean the tube sheets first why clean 00:19:05.46000:19:05.470 the water box twice cleaning the tube 00:19:08.27900:19:08.289 sheets is made easier with the use of 00:19:09.93000:19:09.940 wire picks to get to the inside of the 00:19:12.12000:19:12.130 tubes with the most junk stuck into them 00:19:14.00000:19:14.010 be sure to use care though 00:19:16.63000:19:16.640 some tubes are made of soft metal and 00:19:18.46000:19:18.470 you could damage them bristle or wire 00:19:21.34000:19:21.350 brushes may be used later to get any 00:19:23.38000:19:23.390 slime accumulation from the face of the 00:19:25.36000:19:25.370 tube sheet once the tube sheets been 00:19:28.27000:19:28.280 picked clean our workers make a sort of 00:19:30.88000:19:30.890 two-man bucket brigade passing all the 00:19:33.22000:19:33.230 crud out and dumping it for disposal 00:19:36.72000:19:36.730 shooting the tubes involves the use of a 00:19:39.13000:19:39.140 high-pressure water gun like this one 00:19:40.87000:19:40.880 depending on the kind and amount of 00:19:42.73000:19:42.740 garbage that's blocking the tubes the 00:19:44.80000:19:44.810 mechanic may do the job one of four ways 00:19:47.37000:19:47.380 if there's only mud or silt accumulated 00:19:50.80000:19:50.810 inside the tubes you may just use a 00:19:52.84000:19:52.850 stream of water from the gun 00:19:54.72000:19:54.730 sometimes a gun like this may have a 00:19:56.92000:19:56.930 fitting that allows pumping in 00:19:58.42000:19:58.430 compressed air to turn stubborn 00:19:59.98000:19:59.990 accumulation off the walls of the tubes 00:20:01.72000:20:01.730 a second method he might use is rubber 00:20:05.56000:20:05.570 squeegees that just fit inside the tubes 00:20:07.78000:20:07.790 these are forced through the tubes by 00:20:10.27000:20:10.280 the stream of water they remove slime or 00:20:12.58000:20:12.590 soft deposits from the tube walls better 00:20:14.50000:20:14.510 than water or water and air do the third 00:20:17.68000:20:17.690 thing used to shoot tubes is a tight 00:20:19.42000:20:19.430 fitting wire brush with rubber plugs at 00:20:22.03000:20:22.040 both ends the rubber plug pushes the 00:20:24.64000:20:24.650 brush through on the stream of water 00:20:26.59000:20:26.600 from the gun the plug that goes through 00:20:29.35000:20:29.360 first clears any soft deposits while the 00:20:32.41000:20:32.420 brush removes harder deposits and scale 00:20:35.64000:20:35.650 the fourth item he could use is for 00:20:38.17000:20:38.180 really heavy hard deposits on strong 00:20:40.06000:20:40.070 tube materials such as stainless steel 00:20:42.03000:20:42.040 this bullet is a fend scraper which will 00:20:46.39000:20:46.400 scrape loose chemicals and corrosion 00:20:48.22000:20:48.230 deposits even wire brushes won't remove 00:20:51.84000:20:51.850 in this case the worker is using brushes 00:20:54.46000:20:54.470 to shoot the tubes he inserts a bunch of 00:20:57.28000:20:57.290 them at one time into a section of tubes 00:20:59.14000:20:59.150 he may do several hundred at once when 00:21:03.19000:21:03.200 they're all placed in the tubes he 00:21:04.57000:21:04.580 shoots them through one at a time with 00:21:06.16000:21:06.170 the same high-pressure water gun he uses 00:21:07.96000:21:07.970 when just shooting the tubes with water 00:21:10.29000:21:10.300 it's really important to make sure no 00:21:12.73000:21:12.740 one's in the other water box the force 00:21:14.95000:21:14.960 of the rushes coming through could hurt 00:21:16.54000:21:16.550 someone pretty bad after he's done with 00:21:19.54000:21:19.550 one group of tubes a helper will collect 00:21:21.85000:21:21.860 the bullets from the water box at the 00:21:23.44000:21:23.450 other end while he's doing this our 00:21:25.57000:21:25.580 mechanic places a mother bunch of 00:21:27.10000:21:27.110 bullets into the next group of tubes and 00:21:28.90000:21:28.910 signals his helper 00:21:30.59000:21:30.600 he's ready to shoot them communications 00:21:33.11000:21:33.120 with everyone are really important so no 00:21:35.29900:21:35.309 one will get hurt 00:21:36.46000:21:36.470 to shoot the tubes all he has to do once 00:21:39.68000:21:39.690 the bullets are in place is to hold the 00:21:41.93000:21:41.940 nozzle of the water gun firmly in the 00:21:44.15000:21:44.160 mouth of each tube and pull the trigger 00:21:46.18000:21:46.190 he can feel the water pressure and he 00:21:49.07000:21:49.080 can tell by this feel when the bullet 00:21:50.87000:21:50.880 has gone through and out the other end 00:21:52.70000:21:52.710 of the tube now occasionally the workers 00:21:56.15000:21:56.160 going to find that a tube is blocked so 00:21:58.15900:21:58.169 badly that a bullet won't clear it when 00:22:01.03900:22:01.049 this happens he's going to get wet this 00:22:03.89000:22:03.900 is why he's kept his rain suit on and 00:22:06.02000:22:06.030 why he's wearing safety glasses while 00:22:08.21000:22:08.220 he's performing this chore chemicals in 00:22:11.51000:22:11.520 the deposits or in the water could be 00:22:13.43000:22:13.440 harmful in order to get all the tubes in 00:22:17.14900:22:17.159 the condenser or any big shell and tube 00:22:19.39900:22:19.409 heat exchanger it'll take a fair amount 00:22:21.38000:22:21.390 of time to go through this process over 00:22:23.36000:22:23.370 and over again a bunch at a time 00:22:27.27900:22:27.289 now the basic jobs not much different on 00:22:29.99000:22:30.000 a large shell and tube heat exchanger in 00:22:32.77900:22:32.789 the case of this large heater shooting 00:22:34.78900:22:34.799 the tubes was done with high-pressure 00:22:36.26000:22:36.270 water and compressed air and that was 00:22:38.53900:22:38.549 good enough to remove the small amounts 00:22:40.19000:22:40.200 of scale that were in the tubing 00:22:41.68000:22:41.690 although the tools and implements are 00:22:44.09000:22:44.100 pretty much the same as the ones we saw 00:22:45.95000:22:45.960 the mechanic using on the condenser one 00:22:48.56000:22:48.570 thing you have to think about with a you 00:22:50.27000:22:50.280 tube heat exchanger is what you shoot 00:22:53.02900:22:53.039 the tubes with longer bullets or brushes 00:22:56.36000:22:56.370 can get hung up in the bend and the 00:22:58.13000:22:58.140 tubes when the outsides of the tubes 00:23:01.31000:23:01.320 need to be cleaned it's necessary to 00:23:03.35000:23:03.360 pull the tube bundle out of the heater 00:23:06.64000:23:06.650 this flange is separated and tracks and 00:23:09.77000:23:09.780 slides or rollers are provided inside 00:23:11.81000:23:11.820 the shell to allow the tube bundle to be 00:23:13.73000:23:13.740 pulled out when the tubes are out in the 00:23:16.52000:23:16.530 open you can wire brush scale away in 00:23:20.08000:23:20.090 oil heaters if you have to get all the 00:23:22.85000:23:22.860 oil off the tubes for any reason you can 00:23:24.91900:23:24.929 use solvents made for that purpose now 00:23:27.50000:23:27.510 once all the tubes are cleared and when 00:23:29.81000:23:29.820 water boxes or headers are clean the 00:23:32.21000:23:32.220 next job at hand is finding and plugging 00:23:34.37000:23:34.380 leakage before we follow on to the next 00:23:37.25000:23:37.260 step though we'd like to take a look at 00:23:39.77000:23:39.780 a couple of other ways of keeping shell 00:23:41.72000:23:41.730 and tube heat exchangers clean 00:23:43.92000:23:43.930 one mechanical method some plants use is 00:23:47.20000:23:47.210 sort of like the snake plumber uses to 00:23:50.02000:23:50.030 clean out your home plumbing a rotating 00:23:52.75000:23:52.760 set of blades on the end of a cable is 00:23:54.55000:23:54.560 fed through the tubes in a heat 00:23:55.96000:23:55.970 exchanger to remove very tough scaly 00:23:58.57000:23:58.580 deposits like the scrapers used in 00:24:01.69000:24:01.700 shooting tubes this method of cleaning 00:24:03.82000:24:03.830 is usually reserved for the toughest 00:24:06.01000:24:06.020 cleaning jobs on tubes of strong 00:24:07.93000:24:07.940 material in addition to these 00:24:11.41000:24:11.420 do-it-yourself methods there are some 00:24:13.18000:24:13.190 automatic systems for keeping condensers 00:24:15.31000:24:15.320 and a shell and tube heat exchangers 00:24:16.81000:24:16.820 clean now these automatic systems fall 00:24:19.21000:24:19.220 into two categories the first is 00:24:21.31000:24:21.320 mechanical cleaning and the second is 00:24:23.17000:24:23.180 chemical cleaning automatic mechanical 00:24:26.35000:24:26.360 cleaning systems are found in many 00:24:27.70000:24:27.710 plants that utilize river or ocean water 00:24:30.13000:24:30.140 for cooling water and condensers and 00:24:31.87000:24:31.880 other heat exchangers a common system 00:24:34.57000:24:34.580 circulates rough sponge balls through 00:24:37.24000:24:37.250 the tubes and collects them to be pumped 00:24:39.37000:24:39.380 back through a use of these automatic 00:24:42.13000:24:42.140 systems cuts down on the need for 00:24:43.51000:24:43.520 periodic cleaning where fresh clean 00:24:45.55000:24:45.560 water can't be used in a heat exchanger 00:24:48.63000:24:48.640 chemical cleaning systems automatically 00:24:50.92000:24:50.930 chlorinate the incoming cooling water to 00:24:53.02000:24:53.030 kill and prevent algae growth the 00:24:55.63000:24:55.640 collection of slime on the inside of 00:24:57.37000:24:57.380 tubes and on tube sheets is reduced and 00:25:00.16000:25:00.170 this keeps cleaning jobs to a minimum 00:25:03.60000:25:03.610 altogether the methods we've examined in 00:25:06.58000:25:06.590 this part of the program manual and 00:25:08.65000:25:08.660 automatic are typical of the cleaning 00:25:11.08000:25:11.090 methods used in the plant these methods 00:25:13.87000:25:13.880 are the methods used for larger shell 00:25:15.67000:25:15.680 and tube heat exchangers and for surface 00:25:17.95000:25:17.960 condensers a little later in the program 00:25:20.80000:25:20.810 we'll examine smaller shell and tube 00:25:22.78000:25:22.790 heat exchanger maintenance but before we 00:25:24.55000:25:24.560 do we'll look at maintenance practices 00:25:26.47000:25:26.480 to plug leaks in larger heat exchangers 00:25:29.46000:25:29.470 for the time being pause and read 00:25:31.75000:25:31.760 section 3 of your text and answer the 00:25:33.61000:25:33.62000:25:36.01000:25:36.020 the methods used in your plant to keep 00:25:38.08000:25:38.090 larger surface heat exchangers clean 00:25:40.08000:25:40.090 make sure you have a good understanding 00:25:41.92000:25:41.930 of these methods and ask your instructor 00:25:44.26000:25:44.27000:25:46.47000:25:46.48000:26:02.74000:26:02.750 in the last section of our program we 00:26:05.75000:26:05.760 talked about how there are basically 00:26:07.01000:26:07.020 only two maintenance problems with heat 00:26:08.75000:26:08.760 exchangers a blockage was one of these 00:26:11.06000:26:11.070 problems and we looked at the procedures 00:26:12.98000:26:12.990 you'll use to clear out blockage in 00:26:14.63000:26:14.640 large components we also talked about 00:26:17.00000:26:17.010 cleaning out the heat exchangers before 00:26:19.04000:26:19.050 inspecting them for any evidence of 00:26:20.51000:26:20.520 leakage leakage is the second of the two 00:26:23.69000:26:23.700 problems you'll have to deal with when 00:26:25.37000:26:25.380 you work on heat exchangers and that's 00:26:27.32000:26:27.330 what we're going to be talking about in 00:26:28.61000:26:28.620 this segment we're going to follow mel 00:26:30.95000:26:30.960 and his crew as they look for some 00:26:32.54000:26:32.550 evidence of leakage in the condenser we 00:26:34.43000:26:34.440 saw them cleaning we'll also take a look 00:26:36.68000:26:36.690 inside the big feed water heater we've 00:26:38.42000:26:38.430 seen will show you how leaks are taken 00:26:40.64000:26:40.650 care of in these big components - 00:26:43.24000:26:43.250 earlier on we saw Melanie's helper clean 00:26:46.07000:26:46.080 out the condenser water box they scrape 00:26:48.56000:26:48.570 the tube sheets and picked abri out of 00:26:50.48000:26:50.490 the ends of the tubes then the water box 00:26:52.67000:26:52.680 was shoveled clean finally Mel's helper 00:26:55.97000:26:55.980 shot the tubes of the condenser to clear 00:26:57.92000:26:57.930 them of any crud that had accumulated 00:26:59.21000:26:59.220 inside them now that the water side of 00:27:03.02000:27:03.030 the condensers been cleaned they can 00:27:04.49000:27:04.500 look for tube leaks and you can do this 00:27:06.50000:27:06.510 in a couple of different ways one of 00:27:08.51000:27:08.520 these methods is a very simple test this 00:27:11.39000:27:11.400 test uses the same plastic wrap that's 00:27:13.25000:27:13.260 so popular for use in the kitchen of 00:27:15.17000:27:15.180 course there are many brands of this 00:27:16.73000:27:16.740 wrap available but this is the stuff 00:27:18.86000:27:18.870 that seems to stick to everything even 00:27:20.95000:27:20.960 itself a vacuum is drawn on the shell 00:27:24.77000:27:24.780 side of the condenser as if it were in 00:27:26.66000:27:26.670 operation now this step is unnecessary 00:27:29.24000:27:29.250 if the condenser is operating under 00:27:30.59000:27:30.600 reduced load with it half opened up the 00:27:33.65000:27:33.660 plastic wrap is laid over wetted tube 00:27:35.75000:27:35.760 sheets like wallpaper sheets of plastic 00:27:38.48000:27:38.490 are overlapped so all the ends of the 00:27:40.46000:27:40.470 tubes are covered you do this at both 00:27:42.92000:27:42.930 ends of the tubes so they'll be sealed 00:27:44.84000:27:44.850 off completely if there's a leak in any 00:27:47.99000:27:48.000 tube the plastic wrap will be sucked 00:27:49.88000:27:49.890 into the ends of the tube that's leaking 00:27:51.88000:27:51.890 you can even tell how bad the leak is if 00:27:55.04000:27:55.050 it's big the wrap may be sucked in so 00:27:57.29000:27:57.300 hard it'll pop in the opening 00:28:00.27000:28:00.280 other substances can be used for this 00:28:02.16000:28:02.170 test a soap and water mix or foam can be 00:28:05.04000:28:05.050 brushed over the tube sheet where the 00:28:07.32000:28:07.330 bubbles are sucked in reveals leaking 00:28:09.42000:28:09.430 tubes wherever a leak is found the tube 00:28:12.78000:28:12.790 is plugged at both ends so the cooling 00:28:14.91000:28:14.920 water won't get into the condensate when 00:28:16.98000:28:16.990 the systems running 00:28:18.20000:28:18.210 tubes are plugged like this instead of 00:28:20.55000:28:20.560 being repaired because it isn't possible 00:28:22.44000:28:22.450 to get into the tube bundle to all the 00:28:24.33000:28:24.340 places the tube might be leaking in a 00:28:27.09000:28:27.100 minute we'll see how leaking tubes are 00:28:28.56000:28:28.570 plugged but before we do let's look at 00:28:30.84000:28:30.850 another way we have to look for tube 00:28:32.34000:28:32.350 leaks this is a test that has to be done 00:28:34.92000:28:34.930 when the turbine is shut down now this 00:28:37.41000:28:37.420 way is more involved but it allows you 00:28:39.90000:28:39.910 to find leaks you might not be able to 00:28:41.58000:28:41.590 detect with the vacuum test our second 00:28:44.64000:28:44.650 method uses a fluorescent dye to seek a 00:28:46.65000:28:46.660 leaking tube and here's how it's done 00:28:49.01000:28:49.020 after the water side of the condenser 00:28:51.09000:28:51.100 has been drained and cleaned jacks or 00:28:53.61000:28:53.620 supports are placed under pads on the 00:28:55.65000:28:55.660 condenser this is because the shell of 00:28:57.93000:28:57.940 the condenser is going to be flooded 00:28:59.37000:28:59.380 with water the jacksons supports are 00:29:01.62000:29:01.630 necessary to hold all the extra weight 00:29:03.30000:29:03.310 on the shell remember that many main 00:29:06.81000:29:06.820 steam condensers are suspended below the 00:29:09.18000:29:09.190 turbine and they just won't hold up 00:29:10.77000:29:10.780 under all the water's extra weight once 00:29:14.04000:29:14.050 the supports have been put into place 00:29:15.36000:29:15.370 the operators flood the condenser with 00:29:17.43000:29:17.440 clean water with the fluorescent dye 00:29:19.17000:29:19.180 added as the dye mixes with the water 00:29:22.38000:29:22.390 any leakage from the shell into the 00:29:24.87000:29:24.880 tubes or around to bins will become 00:29:26.88000:29:26.890 visible under black light black light is 00:29:29.70000:29:29.710 the light produced by an ultraviolet 00:29:31.41000:29:31.420 lamp it causes the dye to glow bright 00:29:34.23000:29:34.240 green wherever there's dye coming out 00:29:36.93000:29:36.940 from around a tube end or out of a 00:29:38.82000:29:38.830 leaking tube it'll be easily visible 00:29:40.92000:29:40.930 using this method of inspection so we've 00:29:44.70000:29:44.710 seen a couple of common methods of 00:29:46.29000:29:46.300 locating leaking condenser tubes other 00:29:48.72000:29:48.730 methods may be used but generally any 00:29:50.94000:29:50.950 method used will be a variation of the 00:29:52.80000:29:52.810 two we've seen be sure to learn how it's 00:29:55.68000:29:55.690 done in your plant once the leaking 00:29:59.19000:29:59.200 tubes are found they get plugged to keep 00:30:01.41000:30:01.420 cooling water from contaminating the 00:30:03.15000:30:03.160 condensate in the shell now tubes can be 00:30:06.36000:30:06.370 plugged in one of several ways remember 00:30:09.48000:30:09.490 that to do the job right you have to 00:30:11.76000:30:11.770 plug the tube at both ends to key 00:30:13.90000:30:13.910 the cooling water out there are several 00:30:16.39000:30:16.400 kinds of plugs for this purpose what 00:30:19.24000:30:19.250 kind of plug to use may be chosen by the 00:30:21.73000:30:21.740 components manufacturer or your plant 00:30:24.34000:30:24.350 may have special requirements your 00:30:26.56000:30:26.570 instructor can fill you in on how to 00:30:28.39000:30:28.400 find out in your plant the most common 00:30:31.36000:30:31.370 are made of a fibrous material and are 00:30:33.16000:30:33.170 shaped like the stopper of a bottle 00:30:35.05000:30:35.060 they're tapered so you can fit them into 00:30:37.39000:30:37.400 the two bins and then just hammer them 00:30:39.31000:30:39.320 in tight they'll stay in place partly 00:30:41.92000:30:41.930 because water pressure will push in on 00:30:44.02000:30:44.030 them also the fibrous material of the 00:30:46.51000:30:46.520 plug will tend to expand when it's 00:30:48.04000:30:48.050 soaked with water to hold the plug in 00:30:49.69000:30:49.700 even more tightly other kinds of plugs 00:30:52.84000:30:52.850 are used to do the job to some of the 00:30:55.24000:30:55.250 older plugs used in this condenser has 00:30:57.22000:30:57.230 slotted heads they're threaded plugs 00:31:00.04000:31:00.050 that screw into the ends of the tubes 00:31:02.01000:31:02.020 they cut their own threads sort of like 00:31:04.54000:31:04.550 wood or sheet metal screw the threads 00:31:07.42000:31:07.430 grabbed into the middle of the tube and 00:31:08.98000:31:08.990 hold tight these are metal plugs and 00:31:12.16000:31:12.170 they don't have to expand in place to 00:31:13.90000:31:13.910 hold tight now long experience has shown 00:31:16.51000:31:16.520 that the heat and vibration that's 00:31:18.10000:31:18.110 present when the unit's running doesn't 00:31:20.17000:31:20.180 necessarily loosen plugs too easily 00:31:21.91000:31:21.920 so metal tapered plugs can be hammered 00:31:24.88000:31:24.890 in tightly enough to hold a metal 00:31:27.58000:31:27.590 tapered plug will sometimes seal a minor 00:31:29.83000:31:29.840 leak between the tube and the tube sheet 00:31:31.66000:31:31.670 by forcing the end of the tube more 00:31:33.49000:31:33.500 tightly into the hole in the tube sheet 00:31:35.23000:31:35.240 to be sure it's sealed if there's any 00:31:37.78000:31:37.790 doubt a metal plug can then be welded 00:31:40.27000:31:40.280 around to make a permanent positive seal 00:31:43.74000:31:43.750 another type of plug that sometimes used 00:31:46.09000:31:46.100 to seal a leaking tube is an expandable 00:31:48.10000:31:48.110 plug these have a rubber donut 00:31:50.65000:31:50.660 sandwiched between two large washers 00:31:52.66000:31:52.670 with a bolt running through the middle 00:31:54.10000:31:54.110 and the bolt is tightened the rubber is 00:31:56.83000:31:56.840 forced to expand outward this seals the 00:31:59.80000:31:59.810 tube tightly enough that the plug won't 00:32:01.57000:32:01.580 loosen and come out for extreme service 00:32:04.90000:32:04.910 requirements such as high pressure 00:32:06.40000:32:06.410 heaters and nuclear power plants there 00:32:08.74000:32:08.750 are even explosive plugs that are 00:32:10.60000:32:10.610 detonated to expand them into place now 00:32:14.50000:32:14.510 let's take a look at plugging leaks in a 00:32:15.94000:32:15.950 high-pressure feed water heater here 00:32:18.37000:32:18.380 we'll see two other methods of plugging 00:32:20.41000:32:20.420 tubes and leaks between two bins and 00:32:22.33000:32:22.340 tube sheets this big heater has been 00:32:25.00000:32:25.010 opened because it was known that it had 00:32:26.62000:32:26.630 some leakage 00:32:27.76000:32:27.770 when they open it up they found that 00:32:29.38000:32:29.390 some tubes were leaking and I also found 00:32:31.57000:32:31.580 that some of the two bins had vibrated 00:32:33.16000:32:33.170 loose from the tube sheet and were 00:32:34.57000:32:34.580 allowing leakage to different kinds of 00:32:37.15000:32:37.160 plugs were used in this heater the older 00:32:39.40000:32:39.410 ones are expandable metal plugs the hard 00:32:42.16000:32:42.170 metal pin in the middle is driven in 00:32:44.02000:32:44.030 with a hammer and forces the softer 00:32:45.70000:32:45.710 metal of the plug to expand in the tube 00:32:47.50000:32:47.510 end the others are tapered metal plugs 00:32:50.38000:32:50.390 just installed recently notice that some 00:32:53.53000:32:53.540 of these have been welded in place 00:32:54.93000:32:54.940 they've done this to seal a leak between 00:32:57.43000:32:57.440 the tube end and the tube sheet where 00:33:00.49000:33:00.500 several adjacent tubes may have come 00:33:02.26000:33:02.270 loose at once the whole bunch of them is 00:33:04.51000:33:04.520 welded over to seal any further leakage 00:33:06.93000:33:06.940 if the tubes were much larger in 00:33:09.28000:33:09.290 diameter they might have welded plugs in 00:33:11.79900:33:11.809 the ends of them now whether we're 00:33:14.32000:33:14.330 talking about a condenser or any other 00:33:16.66000:33:16.670 shell and tube heat exchanger there's 00:33:18.58000:33:18.590 only a certain percentage that can be 00:33:20.74000:33:20.750 plugged before the heat exchanger begins 00:33:23.16900:33:23.179 to lose efficiency usually you can plug 00:33:26.53000:33:26.540 between ten and twenty percent before it 00:33:29.08000:33:29.090 affects the components efficiency you 00:33:31.27000:33:31.280 can find out what that percentage is on 00:33:33.37000:33:33.380 the piece you're working on by checking 00:33:35.23000:33:35.240 manufacturer spec sheets for that 00:33:36.97000:33:36.980 component for this reason and also to 00:33:40.06000:33:40.070 make sure that plugs haven't come out 00:33:41.77000:33:41.780 during operation it's important to 00:33:44.02000:33:44.030 record exactly which tubes are plugged 00:33:46.51000:33:46.520 when you know that you're reaching the 00:33:48.70000:33:48.710 maximum percentage you can plan to 00:33:51.04000:33:51.050 replacement well in advance when that 00:33:54.73000:33:54.740 maximum percentage is exceeded it's time 00:33:57.04000:33:57.050 to replace the tubes when that's done 00:33:59.13000:33:59.140 usually all the tubes are done at once 00:34:01.51000:34:01.520 because it's most economical to do it 00:34:03.07000:34:03.080 that way usually a tube replacement is a 00:34:06.19000:34:06.200 job that's contracted out to a refiller 00:34:08.34900:34:08.359 or to the components manufacturer this 00:34:11.26000:34:11.270 may involve having to ship pieces out or 00:34:13.57000:34:13.580 the component may be repaired at your 00:34:15.36900:34:15.379 facility depends on the size of the 00:34:17.05000:34:17.060 component tubes are replaced by 00:34:19.59900:34:19.609 carefully cutting them away from the 00:34:21.36900:34:21.379 tube sheet so the tube sheet isn't 00:34:23.47000:34:23.480 damaged new tubes are installed the same 00:34:26.59000:34:26.600 way the old ones were put in and this 00:34:28.72000:34:28.730 could be one of two ways rolling tubes 00:34:31.51000:34:31.520 is the first way it's a method of 00:34:33.43000:34:33.440 expanding the ends of the tubes into 00:34:35.23000:34:35.240 corrugated holes in the tube sheets the 00:34:37.84000:34:37.850 corrugations hold the tube in place and 00:34:39.73000:34:39.740 provide a strong seal against leak 00:34:42.06000:34:42.070 the second way tubes may be fixed to 00:34:44.62000:34:44.630 tube sheets is by welding this is 00:34:46.90000:34:46.910 usually done for components operating 00:34:48.64000:34:48.650 under high temperature and high pressure 00:34:50.32000:34:50.330 conditions welding is done carefully and 00:34:53.59000:34:53.600 provides a very strong bond between 00:34:55.54000:34:55.550 tubes and tube sheets of compatible 00:34:57.70000:34:57.710 metals in either case it'll probably be 00:35:00.73000:35:00.740 your job to prepare the heat exchanger 00:35:02.86000:35:02.870 for the retooling job and this will mean 00:35:05.20000:35:05.210 you'll have to rig the component to open 00:35:07.00000:35:07.010 it and close up the component after the 00:35:09.19000:35:09.200 tube bundle is back in place this will 00:35:11.98000:35:11.990 involve the careful rigging of the parts 00:35:14.11000:35:14.120 of the heat exchanger gaskets to see a 00:35:16.66000:35:16.670 large header plates and gaskets to see a 00:35:18.67000:35:18.680 large baffle flanges may have to be cut 00:35:20.98000:35:20.990 from big sheets of gasket material the 00:35:23.62000:35:23.630 sealing surfaces will have to be clean 00:35:25.45000:35:25.460 smooth of all old casket material which 00:35:27.79000:35:27.800 may be stuck to it with everything 00:35:30.55000:35:30.560 placed carefully it's a mighty job to 00:35:33.19000:35:33.200 handle the impact wrenches these huge 00:35:35.35000:35:35.360 wrenches have to be rig themselves 00:35:37.48000:35:37.490 they're so heavy it takes two people to 00:35:39.79000:35:39.800 do this task to get these nuts tightened 00:35:42.10000:35:42.110 on the studs after everything's back 00:35:45.79000:35:45.800 together a pressure drop test will be 00:35:47.92000:35:47.930 used to make sure the unit is really 00:35:49.66000:35:49.670 tight now this is a test where one side 00:35:52.21000:35:52.220 of the heaters pressurized and the other 00:35:54.04000:35:54.050 is left open when the pressure source is 00:35:56.77000:35:56.780 closed off any drop in pressure shows 00:35:59.56000:35:59.570 evidence of a leak all these procedures 00:36:02.89000:36:02.900 we've seen in this segment inspection to 00:36:05.29000:36:05.300 find leaks and the ways you have to seal 00:36:07.63000:36:07.640 leaks are part of the procedures you'll 00:36:09.79000:36:09.800 probably follow from time to time when 00:36:11.68000:36:11.690 you're called on to do maintenance on 00:36:13.03000:36:13.040 large heat exchangers in a moment we'll 00:36:16.21000:36:16.220 go on to look at maintenance on smaller 00:36:18.16000:36:18.170 heat exchangers before we do read the 00:36:21.16000:36:21.170 fourth chapter of your text and work the 00:36:22.96000:36:22.970 exercise your instructor can tell you 00:36:25.48000:36:25.490 what work is done to detect and plug 00:36:27.46000:36:27.470 leaks and the large heat exchangers in 00:36:29.14000:36:29.150 your plant any special information on 00:36:31.75000:36:31.760 the unit's you'll be working with can be 00:36:33.40000:36:33.410 found in manufacturers spec sheets and 00:36:35.56000:36:35.570 manuals 00:36:40.64000:36:40.65000:36:52.80000:36:52.810 so far in this program we've seen many 00:36:55.39000:36:55.400 routine maintenance tasks you'll be 00:36:56.92000:36:56.930 performing on large heat exchangers 00:36:58.85900:36:58.869 condensers and big shell and tube heat 00:37:00.88000:37:00.890 exchangers are all dealt with in pretty 00:37:02.89000:37:02.900 much the same way now small heat 00:37:05.71000:37:05.720 exchangers such as this lube oil cooler 00:37:07.75000:37:07.760 have the same kinds of maintenance 00:37:09.97000:37:09.980 problems blockage and leakage but you'll 00:37:12.43000:37:12.440 handle them differently for the most 00:37:14.68000:37:14.690 part heat exchangers used in the plant 00:37:17.02000:37:17.030 fall into two extremes the larger ones 00:37:20.98000:37:20.990 we've examined up till now are fixed in 00:37:22.99000:37:23.000 position and maintained in place smaller 00:37:25.75000:37:25.760 ones on the other hand can be brought 00:37:27.19000:37:27.200 into the shop for their maintenance 00:37:28.51000:37:28.520 they're portable enough for you to pick 00:37:30.52000:37:30.530 them up and handle them what we're going 00:37:33.37000:37:33.380 to do in this part of the program is 00:37:35.08000:37:35.090 look at a typical maintenance routine on 00:37:37.27000:37:37.280 this small cooler specific things like 00:37:41.20000:37:41.210 where the inlets and the outlets are and 00:37:44.05000:37:44.060 the configuration of the headers may 00:37:46.90000:37:46.910 vary among different units but the 00:37:48.94000:37:48.950 things we'll be seeing are basic to most 00:37:51.04000:37:51.050 all the small shell and tube heat 00:37:52.69000:37:52.700 exchangers you'll be working on these 00:37:56.58900:37:56.599 mechanics have already removed the lube 00:37:58.45000:37:58.460 oil cooler from the motor pump assembly 00:38:00.31000:38:00.320 it was serving since the system had to 00:38:03.16000:38:03.170 be put back in service immediately they 00:38:05.74000:38:05.750 replaced it with a unit that had 00:38:07.24000:38:07.250 previously been rebuilt they pressure 00:38:10.45000:38:10.460 checked this one to see if there were 00:38:12.31000:38:12.320 any leaks before they rebuilt it what 00:38:15.31000:38:15.320 they'll do now is open this one clean it 00:38:17.68000:38:17.690 out thoroughly replace gaskets and seals 00:38:19.75000:38:19.760 and test it then they'll put it back 00:38:22.69000:38:22.700 into stock until another one like it 00:38:24.33900:38:24.349 needs service the first step is to drain 00:38:27.84900:38:27.859 the cooler thoroughly when they've 00:38:29.80000:38:29.810 gotten as much out as possible the front 00:38:32.20000:38:32.210 header is loosened so the seal can be 00:38:34.35900:38:34.369 broken this way the rest of the oil and 00:38:37.35900:38:37.369 water can be drained from the tubes in 00:38:38.95000:38:38.960 the shell once both fluids have been 00:38:42.09900:38:42.109 drained from the cooler the guys can 00:38:44.29000:38:44.300 finish taking it apart without spreading 00:38:46.35900:38:46.369 the mess too much first he removes the 00:38:49.78000:38:49.790 front header this is the header he had 00:38:52.18000:38:52.190 loosened to finish draining the unit 00:38:54.06000:38:54.070 with the header off it's pretty easy to 00:38:56.82900:38:56.839 see why they're having to work on this 00:38:58.51000:38:58.520 coup 00:38:59.14000:38:59.150 all that build-up comes from the cooling 00:39:01.90000:39:01.910 water flowing through the tube side 00:39:04.09000:39:04.100 the water is unpurified river water and 00:39:07.60000:39:07.610 the accumulation of silt and slime is a 00:39:10.36000:39:10.370 lot like some of the junk that collects 00:39:12.64000:39:12.650 in a condenser next off comes the header 00:39:16.39000:39:16.400 at the other end 00:39:17.50000:39:17.510 notice the rotation cycle of loosening 00:39:20.44000:39:20.450 the bolts until they are free from 00:39:22.36000:39:22.370 tension on the shell and header this is 00:39:25.06000:39:25.070 to prevent any possibility of warping 00:39:27.22000:39:27.230 the header or the shell once each header 00:39:30.88000:39:30.890 is removed the hardware is set carefully 00:39:33.40000:39:33.410 aside so it doesn't get lost the 00:39:36.70000:39:36.710 mechanic now has access to both ends of 00:39:39.16000:39:39.170 the tube bundle and both tube sheets can 00:39:41.65000:39:41.660 be scraped clean he's doing the step of 00:39:44.68000:39:44.690 cleaning with a putty knife 00:39:45.70000:39:45.710 using care not to gouge the tubes on the 00:39:48.37000:39:48.380 tube sheet he's not likely to cause any 00:39:51.88000:39:51.890 harm but it is possible to do damage 00:39:53.80000:39:53.810 that might cause leaks when the tube 00:39:57.04000:39:57.050 sheets are scraped he wipes them clean 00:39:59.26000:39:59.270 with a rag now he's ready to rot out the 00:40:02.98000:40:02.990 tubes the rod has an end which fits 00:40:06.58000:40:06.590 snugly inside the tubes and as it's 00:40:09.28000:40:09.290 pushed through each one drives all the 00:40:11.44000:40:11.450 accumulated sludge out of the other open 00:40:13.93000:40:13.940 end it doesn't make any difference what 00:40:16.48000:40:16.490 direction the tubes are rotted in both 00:40:19.03000:40:19.040 ends are the same and they're both open 00:40:21.75000:40:21.760 after rotting each tube the mechanic 00:40:24.67000:40:24.680 wipes off any remaining sludge from the 00:40:26.53000:40:26.540 tube sheets cleaning the gasket surfaces 00:40:29.95000:40:29.960 at each end of the shell comes next 00:40:31.62000:40:31.630 using a scraper the flat surfaces have 00:40:34.96000:40:34.970 to be cleaned to bare metal they can't 00:40:37.72000:40:37.730 leave any old gasket material stuck to 00:40:40.09000:40:40.100 the mating surfaces that would keep them 00:40:41.83000:40:41.840 from sealing tightly once the last 00:40:45.79000:40:45.800 little bit is removed the shell and tube 00:40:48.40000:40:48.410 bundle can be set aside and it's time to 00:40:51.04000:40:51.050 work on the headers our mechanic needs a 00:40:54.34000:40:54.350 putty knife to dig out the sludge from 00:40:56.29000:40:56.300 inside the headers he gouges out the 00:40:59.47000:40:59.480 last little bit before he scrapes the 00:41:01.33000:41:01.340 gasket area clean he's got to be just as 00:41:05.08000:41:05.090 thorough as when he cleaned the gasket 00:41:07.18000:41:07.190 mating surfaces on the show every bit of 00:41:10.69000:41:10.700 old gasket has got to go 00:41:13.10900:41:13.119 the surfaces have to be smooth bare 00:41:16.21000:41:16.220 metal in order to get a good seal he 00:41:19.27000:41:19.280 goes through the same routine to clean 00:41:20.83000:41:20.840 the other header first he gets all the 00:41:23.17000:41:23.180 accumulation out of the inside then he 00:41:25.93000:41:25.940 scrapes the gasket surfaces clean so the 00:41:28.57000:41:28.580 seal will be good when the cooler goes 00:41:30.40000:41:30.410 back together when all this is done he 00:41:33.76000:41:33.770 makes a final close inspection of all 00:41:36.19000:41:36.200 the parts to make sure he hasn't 00:41:37.87000:41:37.880 overlooked anything he's also looking 00:41:40.39000:41:40.400 for any damage that might be apparent if 00:41:43.30000:41:43.310 any were found it would have to be 00:41:45.22000:41:45.230 corrected before he reassembles the 00:41:47.02000:41:47.030 component now it's time to lay out all 00:41:50.29000:41:50.300 the materials and hardware to put the 00:41:52.33000:41:52.340 cooler back together again when he 00:41:55.66000:41:55.670 reassembles the cooler he carefully 00:41:57.46000:41:57.470 checks the fit of each gasket then he 00:42:00.76000:42:00.770 uses a light complete coating of gaskets 00:42:03.49000:42:03.500 cement on the mating surface of the 00:42:05.74000:42:05.750 shell this will hold the gasket in place 00:42:08.38000:42:08.390 so it will stay perfectly aligned when 00:42:10.96000:42:10.970 the header is put on gasket cement also 00:42:14.38000:42:14.390 helps provide a more perfect seal so he 00:42:17.32000:42:17.330 smooths the coating on the other mating 00:42:19.30000:42:19.310 surface - then it's back on with the 00:42:22.66000:42:22.670 header carefully making sure everything 00:42:25.15000:42:25.160 lines up just so while he holds the 00:42:29.65000:42:29.660 header in place with one hand he threads 00:42:31.99000:42:32.000 the nuts onto the studs carefully and 00:42:34.57000:42:34.580 runs them down by hand until they are 00:42:36.76000:42:36.770 finger tight one by one each nut is 00:42:40.54000:42:40.550 threaded on to the studs until they are 00:42:42.52000:42:42.530 all snug when all the nuts are tightened 00:42:46.30000:42:46.310 down in this manner he takes a hand 00:42:48.67000:42:48.680 wrench to tighten them the rest of the 00:42:50.34900:42:50.359 way in order to make sure the header is 00:42:53.08000:42:53.090 tightened down uniformly he tightens the 00:42:55.72000:42:55.730 nuts in a crisscross pattern this 00:42:58.99000:42:59.000 assures that the parts will not warp and 00:43:01.54000:43:01.550 that the gaskets will provide a tight 00:43:03.73000:43:03.740 seal now some heat exchangers like this 00:43:07.39000:43:07.400 one may require the nuts to be tightened 00:43:09.52000:43:09.530 with a torque wrench whenever you're 00:43:12.58000:43:12.590 working on a piece of equipment check of 00:43:14.50000:43:14.510 the manufacturers manual or maintenance 00:43:16.59900:43:16.609 bulletin will tell you torquing 00:43:18.34000:43:18.350 requirements it'll give you any other 00:43:21.28000:43:21.290 special information you need to know - 00:43:22.99000:43:23.000 on this particular cooler the 00:43:26.24000:43:26.250 manufacturer doesn't specify the torque 00:43:28.58000:43:28.590 required to tighten the nuts so the 00:43:30.77000:43:30.780 mechanic uses careful judgment to 00:43:32.57000:43:32.580 tighten the nuts uniformly he's also 00:43:35.36000:43:35.370 careful to avoid twisting that wrench 00:43:37.31000:43:37.320 too hard he doesn't want to take a 00:43:39.62000:43:39.630 chance on stripping the threads on the 00:43:41.36000:43:41.370 studs after the other headers back on 00:43:45.23000:43:45.240 when everything's up tight a final 00:43:47.81000:43:47.820 external cleaning with a rag is just 00:43:49.85000:43:49.860 plain good practice the last step before 00:43:54.29000:43:54.300 they put the cooler back in the 00:43:55.70000:43:55.710 storeroom for the next time it'll be 00:43:57.14000:43:57.150 needed is to check and make sure there 00:43:59.81000:43:59.820 are no leaks and one way to do this is 00:44:01.85000:44:01.860 to hook up the tube side inlet to the 00:44:04.43000:44:04.440 usual cooling water system and then 00:44:06.83000:44:06.840 plugging the outlet now when the valve 00:44:09.41000:44:09.420 is open to allow water to flow there 00:44:11.45000:44:11.460 should be no evidence of leakage either 00:44:13.52000:44:13.530 at the gaskets or into the shell from 00:44:16.10000:44:16.110 the tube bundle another way of checking 00:44:18.62000:44:18.630 for leaks is a little cleaner since you 00:44:20.90000:44:20.910 don't have to use cooling water to look 00:44:22.73000:44:22.740 for leaks all you do is plug the outlet 00:44:25.16000:44:25.170 as before but the inlet is connected to 00:44:28.58000:44:28.590 a source of compressed air with a gauge 00:44:30.95000:44:30.960 between the valve and the cooler the 00:44:33.11000:44:33.120 valve is opened and the shell is 00:44:34.82000:44:34.830 pressurized you've got to be careful 00:44:37.04000:44:37.050 here not to use too much pressure or you 00:44:39.17000:44:39.180 could cause a lot of damage to the 00:44:40.70000:44:40.710 cooler then the valve is closed and you 00:44:43.97000:44:43.980 watch the gauge to see if there's any 00:44:46.25000:44:46.260 drop in the pressure in the shell if not 00:44:49.07000:44:49.080 you can figure the component is leak 00:44:51.11000:44:51.120 tight these are the same types of tests 00:44:55.01000:44:55.020 they might have used before they took 00:44:56.51000:44:56.520 the cooler apart after it passes the 00:44:59.15000:44:59.160 leakage test it's ready to go back on 00:45:01.22000:45:01.230 the shelf for future use if any leaks 00:45:03.95000:45:03.960 are found usually it's easier to replace 00:45:06.11000:45:06.120 the tube bundle with a new or rebuilt 00:45:07.97000:45:07.980 one later on the tube bundle can be 00:45:10.58000:45:10.590 rebuilt and put back for future service 00:45:13.09000:45:13.100 from our we've seen in this unit 00:45:15.35000:45:15.360 maintenance on shell and tube heat 00:45:16.82000:45:16.830 exchangers is pretty basic once you have 00:45:18.92000:45:18.930 an understanding of how they work and 00:45:20.60000:45:20.610 how they're made you'll only be looking 00:45:22.91000:45:22.920 for ways to fix two heat exchanger 00:45:24.83000:45:24.840 maintenance problems blockage and 00:45:26.78000:45:26.790 leakage and the way you'll be dealing 00:45:29.48000:45:29.490 with these problems will depend on the 00:45:31.16000:45:31.170 physical size of the component as well 00:45:33.44000:45:33.450 as the circumstances of its use none of 00:45:36.74000:45:36.750 it is all that difficult but just like 00:45:39.11000:45:39.120 any mechanical 00:45:40.10000:45:40.110 it needs your attention to doing the job 00:45:42.41000:45:42.420 right to avoid problems later on when 00:45:45.59000:45:45.600 you've completed the exercises on heat 00:45:47.27000:45:47.280 exchangers you'll be ready to tackle any 00:45:49.46000:45:49.470 of these jobs in your plant 00:45:51.51000:45:51.520
Office location
Engineering company LOTUS®
Russia, Ekaterinburg, Lunacharskogo street, 240/12