# Coffin feed pumps



## Steve Hodges

Some recent correspondence in the BP Shipping forum got onto the subject of Coffin feed pumps, and it turns out that I was not alone in being frightened of the things! I only ever came across them on the BP "P" clas VLCCs built in Holland, but I'm assuming that they must have been pretty common in US built steamers. Was everybody frightened of them?
From memory, and it's a helluva long time ago, they normally ran at 10,000 rpm and simply screamed like a jet aircraft. The lubrication of the roller bearings was by a high-volume oil wash system. On one ship, one of these oil supply lines was blocked by something ( a bit of PTFE tape I think) and the bearing ran dry. I was on engineroom rounds at the time, heard the normal screaming going decidedly odd, and when I got to it the whole bearing housing was red hot with sparks streaming from it. I thought - briefly - about shutting it down locally, but then I just ran away, to be honest! By the time I got to the control room I think it had seized solid, but we got the electric pump going before we lost everything. If I remember correctly, when it was stripped the bearing inner race had welded itself to the shaft and had to be ground off. The 2/E did get it going again eventually, but we never really trusted it again and used to run the other one all the time.
The BP Planned Maintenace schedules said that we had to test the overspeed trips on these things something like once a month. The speed governor was hydraulic, so the procedure was to put a lever into the nozzle valve linkage and heave - the speed would shoot up , but the governor would fight back , so you had to heave harder and harder to try to get up to trip speed, which was from ( my now decidely failing) memory around 13,000 rpm. In the meantime, a junior engineer would be kneeling at the end of the unit with a tacho on the end of the shaft. As the speed shot up and the screaming went up several octaves , their nerve would often go and they would just drop the tacho and leg it. I must confess that the overspeed trip test on the PM sheet was frequently falsified!
It may well be that 35 years have made these memories even more lurid, but I think I can honestly say that Coffin feed pumps were the only things I ever met in an engine room that I was truly frightened of! Anyone else care to confess? Or are US marine engineers a hardier breed?


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## Basil

On the Fyffes ships, we'd a couple of turbo feed pumps on the starting platform.
Would those have been Coffin pumps?
Certainly made a heck of a 'ZZZZZZZ' noise for which I blame my reduced auditory acuity (together with RR Dart turboprops, jets various and aircraft air conditioning packs - also turbine)

p.s. Re subsequent posts, ours were probably Weir's. Never had to open one up - TF!


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## makko

I was wracking my own memory about this.......Turbine driven feed pumps.
"Coffin" was the trademark from the family name, see the link:

http://www.compasswater.com/history.html

Rgds.
Dave


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## spongebob

Google 'Coffin pumps' and find them alive and well. 
I have heard of them but not ever used one but like the Weir turbo pump those high rpm's can be alarming at times.

Bob


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## David Campbell

My first ship the Esso T2 "Saguaro" had Coffin feed pumps. Do not recall any peculiar noise. I guess a lot of T2's had Coffin feed pumps


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## kewl dude

I sailed several ships with Coffin feed pumps. On T2's a pair were mounted on a platform about 3 feet above the floor plates on the starboard side of the shaft alley. They were controlled by reach rods to the fire room operating position. Sometimes the valves grew out of the deck alongside the boiler corner. Others the valves were in front of the combustion control board like the attached picture.

I do not recall any unusual noises. I do recall that they were impossible to get apart when needed. The only realistic way was to torch cut the main shaft between the turbine and pump. The shaft exited the casing on the bottom with just enough room to burn it in half. So any overhaul required a new shaft. 

I was under the impression that the reason they were so popular was their cost was much less than horizontal or vertical multi-stage pumps, with an external steam turbine? They were also more compact and lighter in weight in the 450-600 pound operating range. I saw some 1200 pound Coffins on a US Navy ship and they were huge in comparison.

Greg Hayden


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## Malky Glaister

I recall on a couple of Maersk steamtankers a Coffin feedpump driven directly off the turbo alternator shaft. Steam end.
The second pump was conventional, if that s the word,direct steamturbine drive. It had a relatively large Woodward governo rbolted onto it,s top at an angle.
The word COFFIN never inspired me much!

I much preferred the WEIR TWA pumps.

regards

Malky


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## surfaceblow

I did not have any problems with the Coffin Feed Pumps they were the norm for all of the steam plants I sailed on. Some of the Mariners had Pacific Feed Pumps which were bigger and the governor had a habit of falling apart if you tried to reset it with the turbine still spinning. 

The problems started with the Coffin Feed Pumps when the packing was changed to the non asbestos type. Later mechanical seals where used which improved some worries but it created others. With the asbestos packing the average time between overhauls was 2 to 3 years most of the companies would have a specialty company come in to do the major overhaul. When the packing was changed to non asbestos it was every six months of replacing the packing. We also had to test the overspeed trips on the coffin feed pumps but we used the reach rods for that exercise. 

Joe


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## Steve Hodges

spongebob said:


> Google 'Coffin pumps' and find them alive and well.
> I have heard of them but not ever used one but like the Weir turbo pump those high rpm's can be alarming at times.
> 
> Bob


Weir turbine feed pumps never really bothered me, they always seemed solid and heavily engineered, whereas the Coffins I sailed with gave the impresssion of light construction running absolutely flat out. Another poster on the BP forum mentioned hearing a story of one coming apart and badly injuring a BP 2/E - I wonder if that was true or just apocryphal?


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## stevekelly10

Steve Hodges said:


> Weir turbine feed pumps never really bothered me, they always seemed solid and heavily engineered, whereas the Coffins I sailed with gave the impresssion of light construction running absolutely flat out. Another poster on the BP forum mentioned hearing a story of one coming apart and badly injuring a BP 2/E - I wonder if that was true or just apocryphal?


I'm afraid it is true, as I actually sailed with that particular 2/E post the event and that's were my initial dislike of coffin feed pumps started! I've heard other horror stories concerning these pumps too.
My own experience of these infernal machines was mostly when I was 2/E with Stena Bulk\Concordia maritime, sailing on the ULCC's Stena King or Stena Queen. The Stena King was used as a testbed for the first seagoing test for mechanical seals fitted to a DEB22 Coffin feed pump. The test was successful so the other pump was fitted with mechanical seals, next drydock in Dubai and the Stena Queen's feed pumps were done at her next drydocking. all the seals were fitted by 2 greek service engineers that worked for Marship, a coffin feed pump specialist. The two service engineers were actually a father and son team, that spent more time arguing or fighting with each other, but that's another story . I was the 2/E during both drydockings and had to witness the tests of the overspeed after overhaul and I admit I was hiding behind a large column when they did it 
Some years later the Stena King was left stranded mid Atlantic when both feed pumps destroyed themselves within 20 mins of each other!
and unfortunately there was no electro feed pump as a back up! I was on the Stena Queen at this time and we were ordered to rendevous with the King and pass over any feed pump spares we had or to take the King in tow if needed. Fortunately the King had onboard a plasma cutter, that was used and needed to dismantle both pumps. They eventually managed to salvage enough parts to get one pump going and limp into Capetown.
The reason both pumps failed, I am afraid to say was down to a certain nameless person shutting off the hydraulic balance valve instead of the manual re-circ valve as the auto recirc valves were known to be passing. The culprit never owned up to what he had done and tried to blame the oil foaming for the failure, A load of C**P !


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## Burntisland Ship Yard

Probably with a few exceptions Coffin feedwater pumps were standard on the Texaco Steam ships, for me I did not recall high pitched noises. However, I do recall the standard 15 inch steel strip with a sharp end that was used to jack open the governor to start them up..........


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## surfaceblow

Burntisland Ship Yard said:


> Probably with a few exceptions Coffin feedwater pumps were standard on the Texaco Steam ships, for me I did not recall high pitched noises. However, I do recall the standard 15 inch steel strip with a sharp end that was used to jack open the governor to start them up..........


The newer models had an electric lube oil pump so you no longer had to lift the governor by hand. After the feed pump was up to speed the electric pump would stop when the gear pump oil pressure switch opened. The pry bars was never far away from the feed pump. 

Joe


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## jamesgpobog

Oh bloody hell, I read that name, and it sure sounds familiar. I think we had them on Mispillion (a US Navy T3-S2-A3 jumboized oiler), and here's a pic form January 2012.

If these are Coffin's, yes, they scared the hell out of me, but I really don't know exactly what was going on internally that made them so scary. Beyond the basic understanding of a turbo pump, I really didn't have an understanding of how they worked.

What scared me about them is that they seemed to always be running balls out and for some reason they would pound...you could hear and see these thumps that would make them jump (or seem to) on their foundations. I don't know if it was small slugs of water in the steam side or what, but I did not like them one bit.


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## surfaceblow

jamesgpobog said:


> Oh bloody hell, I read that name, and it sure sounds familiar. I think we had them on Mispillion (a US Navy T3-S2-A3 jumboized oiler), and here's a pic form January 2012.
> 
> If these are Coffin's, yes, they scared the hell out of me, but I really don't know exactly what was going on internally that made them so scary. Beyond the basic understanding of a turbo pump, I really didn't have an understanding of how they worked.
> 
> What scared me about them is that they seemed to always be running balls out and for some reason they would pound...you could hear and see these thumps that would make them jump (or seem to) on their foundations. I don't know if it was small slugs of water in the steam side or what, but I did not like them one bit.


The pounding noise was most likely the Feed Water being too hot and flashing into steam in the pump impeller or a collapsing air bubble. It was a balancing act of how much the recir valve was open to keep the pump impeller full of water and the amount of steam required to get enough water into the steam drum. You did not want the pump getting too close to Over speed trip setting or having the steam governor full open, but it was normal to crack open the extra nozzle valve to get the governor operating in it's mid range. Another point of trouble was the vent on the DC Heater was not open enough to vent the air from the feed water. Then the pump end would become air bound and there would be no water getting to the boiler. 

Water in the steam end would have made a total mess of the plant operation. All of the turbine driven machinery would slow down and speed up. It is very hard to get water into the Auxiliary Steam line but not impossible. I was on port watch eating super when the a Feed Regulator failed. The Chief Engineer did not believe in having a proper chow relief in port so only the oiler was in the Engineroom. By the time I returned to the Engineroom water had gotten to the both generators the low pressure (used Auxiliary Steam and can use the Surface Condenser) and the high pressure generators. The frequency meter broke. The Emergency Diesel started but the circuit breaker would not close. (Sand Blast Grit got into the breaker mechanism Chief Engineer and Captain did not believe in testing the generator under load). The Auxiliary Steam would have made a pass thur the superheater than back into the desuperheater pipe of the steam drum to ensure that there was no water in the the steam line and lowering the stam temperature before going to the feed pump and the other consumers of Auxilary Steam. 

Joe


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## jamesgpobog

surfaceblow said:


> The pounding noise was most likely the Feed Water being too hot and flashing into steam in the pump impeller or a collapsing air bubble. It was a balancing act of how much the recir valve was open to keep the pump impeller full of water and the amount of steam required to get enough water into the steam drum. You did not want the pump getting too close to Over speed trip setting or having the steam governor full open, but it was normal to crack open the extra nozzle valve to get the governor operating in it's mid range. Another point of trouble was the vent on the DC Heater was not open enough to vent the air from the feed water. Then the pump end would become air bound and there would be no water getting to the boiler.
> 
> Water in the steam end would have made a total mess of the plant operation. All of the turbine driven machinery would slow down and speed up. It is very hard to get water into the Auxiliary Steam line but not impossible. I was on port watch eating super when the a Feed Regulator failed. The Chief Engineer did not believe in having a proper chow relief in port so only the oiler was in the Engineroom. By the time I returned to the Engineroom water had gotten to the both generators the low pressure (used Auxiliary Steam and can use the Surface Condenser) and the high pressure generators. The frequency meter broke. The Emergency Diesel started but the circuit breaker would not close. (Sand Blast Grit got into the breaker mechanism Chief Engineer and Captain did not believe in testing the generator under load). The Auxiliary Steam would have made a pass thur the superheater than back into the desuperheater pipe of the steam drum to ensure that there was no water in the the steam line and lowering the stam temperature before going to the feed pump and the other consumers of Auxilary Steam.
> 
> Joe


Thanks for that, Joe, though Time has made many of the details you write of rather....opaque. 

I will say this though, your first part I think I concur with. We had 4 B&W sectional header boilers, 4 burners, 450lbs. Often steamed on 2, sometimes 3, rarely 4, but I do not remember ever being short of feed water, and we never had a water casualty, high or low. 

"Pounding" is a good word, and what you said about the water vs steam sides makes sense. My bet is that it was that flashing to steam, in my gut that rings true. I also do not remember doing much to them in the way of adjustments as they ran. They just were sort of there on their own....pounding away. And as I think of it, it's possible that they pounded most when under load, don't really remember them doing it steaming pierside for example...

And I don't know if it was imagination or not, but it sure seemed like I could see those things move, like 1 quarter inch.


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## Harrisman

Coffin feed pumps were no problem until they changed from the original 'asbestos' type gland packing to what I called dogs***t packing which failed sometimes even before the pump was run up to full speed. After many an argument about whether we were running it in properly the Japanese coffin rep came on board and repacked it and it failed just before full speed. Thought I was going to have a case of 'Hari Kari' on my hands !!! Then then admitted they had changed the packing material. Eventually sourced 'original' packing and no problem


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## chadburn

Serpant "A"


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## Satanic Mechanic

Harrisman said:


> Coffin feed pumps were no problem until they changed from the original 'asbestos' type gland packing to what I called dogs***t packing which failed sometimes even before the pump was run up to full speed. After many an argument about whether we were running it in properly the Japanese coffin rep came on board and repacked it and it failed just before full speed. Thought I was going to have a case of 'Hari Kari' on my hands !!! Then then admitted they had changed the packing material. Eventually sourced 'original' packing and no problem


The move to non asbestos was awful, they kept issuing a new improved versions, whose improvements could be measured in minutes up until packing No.7 - which I must admit was an improvement and could be relied on, but still wasnt as good as asbestos. We eventually moved to mechanical seals which I must say were ace.

As pumps I never really had a problem with them, you had to be methodical in overhauling them for sure but non asbestos packing aside they pretty much just did their thang without any undue fuss.

Japanese rep - not from Tokyo Sanyo by any chance?


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## Jim S

James Walker's "Suppeta" - I am not sure of the spelling - was the gland packing of choice for Weir's turbo-feed pumps. It gave long service provided it was allowed a small (lubricating) leak. Nipped up too tightly and it would soon protest by overheating with potential of damaging the pump shaft.
The RN Tribal Class Frigates had mechanical seals on the Weir Boiler Feed Pumps with the addition of auxiliary conventional packed gland as a safeguard against failure of the mechanical seal - first time I had seen such an arrangement - The auxiliary gland was left lightly packed to be nipped up if required.


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## Ghost

The pumps were reliable untill Coffin changed away from the asbestos gland packing. ToT set up a "coffin crew", two pro 3rds to go out to ships to help with the repair of feed pumps. After ToT I sailed with other fleets on ULCCs and all had big coffin pumps. The screaming was unfortunatly all too common on pumps which had been de-rated for vessel slow steaming, but were supposed to be capable of supplying enough water at full boiler load. Then all the extra nozzles would need to be opened. Later on I was permanent Chief on an even bigger ULCC, but this ship had 2 Pacific pumps. When we did the special survey (at 19 yrs), neither of the pumps had *ever* been touched, they just hummed away, and not a drop of leakage. Now that was reliability. I have often wondered if the pumps were ever opened up before she was beached, and what sort of wear they may have had.


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## steamer659

The vessel that I am currently C/E aboard have four of the largest Coffin Main Feed Pumps ever built, DEB two stage pumps, the seven sisterships have the same.

I have worked mostly with Coffin Feed Pumps throughout my career, most were trouble free, but with a couple of notable exceptions- they can be nightmares when people rebuild them incorrectly. The main rotor MUST have a run out of below .0015" because of the speed, but also there was a lot of consternation when the asbestos based packing was phased out. 

I believe that these pumps were also installed on old steam locomotives (Challenger Class?) and worked out very well. These pumps were exceptional in their design and as above, gave many years of trouble free service when properly maintained and operated. The mechanical seal retrofit was a very welcome addition, but extremely costly...


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## twogrumpy

On BP's R boats with Coffin feed pumps the bearings were fitted with thermal switches which operated on hi temp, nothing fancy cylindrical type with no calibrated scale.
As part of a routine the operation had to be checked, so removed, tested and refitted. Feed pump run up and several days later the Hi temp alarm operated, watchkeeper asked me to set the switch up a bit, no way says I, see the 2/E if he wants it done he can ask me, so the switch was tweeked up. If I recall correctly we went through this performance 3 times before it seized.
So the moral is??

Other than the above incident they did seem to be quite reliable, but I believe many found it hard to understand why Mitsubshi units had not been fitted as all their gear was so reliable.

Well other than when the manouvering valve stuck open entering Khor Alamaya anchorage DS Ahead and still doing about 85 RPM, but thats another story.

2G(Cloud)


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## John Owens

steamer659 said:


> The vessel that I am currently C/E aboard have four of the largest Coffin Main Feed Pumps ever built, DEB two stage pumps, the seven sisterships have the same.


It sounds like you're talking about the SL7s. If so, they must have changed out the feed pumps at some point. I seem to remember they had Worthington feed pumps when I sailed on them in the 70's (real nightmare pumps). Or maybe my memory needs changing out.


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## Varley

I'd no idea the SL7s were still afloat and operating. Saw them occasionally on the GTVs - Didn't seem to be much of them that wasn't engineroom.


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## T2Guy

Not a hardier breed, assuredly, but more familiar with these beasts. I remember as 2nd, a start-up involving loss of head to the pumps. Saw the distilled tank was empty, realized there was nowhere else to go, and ran below to trip the bastard. DEB (double ended bastard). Trip lever was frozen. Climbed on top to close the steam stop, and felt the whole thing disintegrate. Yeah, a very spiritual moment.
Later, Weedon Engineering, of Louisiana fame, came aboard. Mr. Weedon himself, said that "In 50 years, I never seen one come outta the case". "You're a good hand." I guess I was a pussy, but it was still pretty scary. Never really feared them again, until a ship with superheated steam to the pumps with separate attemperating gear. What a nightmare that was. Just waiting for a burndown.


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## waffle-sproket

After the Wier TWL feed pumps on the Norther Star the Coffin feed pumps were fantastic when I joined the Kuwait Oil Tanker Fleet.


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## chuckgregg

*Coffin feedpumps*

Hi, as a T2 man with StanVac I found these feed pumps excellent it was the 3rds job to maintain and once a year stripdown and give them a thorough going over ,and in my experience they never give any problems except may the governors and run from one drydock to the next . The similar pump was the Pacific but not as good. Andrew Weir pumps were nowhere near as good with whitemetal bearings.


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## alaric

waffle-sproket said:


> After the Wier TWL feed pumps on the Norther Star the Coffin feed pumps were fantastic when I joined the Kuwait Oil Tanker Fleet.


Did the TWL pumps continue to give trouble after Northern Star's second voyage?
This is an extract from an article I have written for the Shaw Savill Society newsletter that outlines some of the machinery problems that occured during the first year of this ship's short life.
I would like to hear of other problems that continued in the later years.

_While the concept and overall design of Southern Cross had been revolutionary, the machinery specification and design were conservative, to limit the overall risks being taken. This was a wise strategy, as the ship proved to be very reliable in service and was still going strong when finally scrapped in 2003.
With the overall principal proven to be correct, the company was more adventurous with the specification of Northern Star’s machinery. With hindsight, it can be seen that in some respects they were too adventurous.

One of the innovations was the new, compact design of boiler feed pumps by G&J Weirs of Cathcart. They had a single, central bearing lubricated by water tapped off the high pressure pump discharge.
Traditional turbo feed pumps had three, oil lubricated bearings. These traditional pumps were very reliable, but big and expensive to make in comparison to the new design. I believe that Northern Star was the first ship to rely entirely on the new pumps. With the space available, there was simply no space for traditional pumps, even if it would have been preferred. There were two main pumps, only one of which was required for full power, plus a smaller Harbour Pump, and this would probably have had capacity to steam the ship at 15 knots on its own. The risk of relying totally on the new pumps was probably considered to be small and acceptable. After Clyde trials, Northern Star anchored at Tail of the Bank, and Weirs sent a team on board, and at least one of the pumps was replaced, as mentioned in part1.

The pumps proved to be problematic to start. Once they were up and running they were OK, but if run up to speed too fast, it was liable to seize because the bearing was running too fast before a proper water lubricating film was established. On the other hand, if it was run up to speed too slowly, it was liable to seize because the bearing was running for too long before a proper water lubricating film was established. The window between what was too fast and too slow was very small, and could only be determined by “feel”. Not surprisingly, a number of pump seizures had occurred, some on V1, but these had occurred singularly, so were not critical to the overall operation of the ship. This all changed outward bound on V2 at Cape Town.





At ports where the ship stayed at the berth only 12 hours or less, a main boiler was maintained under steam and the turbo alternators were kept on load for electric power. At Cape Town, a 24hr port, it was usual for the diesel generators to be run for electric power, with the main boilers and steam systems totally shut down. Your writer was still the Junior Engineer on Doc Lovatt’s 4 to 8 watch, so it fell to me to run up and warm through the machinery for the morning departure. All was going well until I attempted to start the Harbour Pump. I think I tried the fast start, but it was too fast and the pump seized up. Doc was not impressed when I told him, so personally took over the job of getting a main pump running. He tried the slow approach, but was too slow, resulting in two of our three pumps now being u/s. Staff Chief Jack Warden was now called from his bed. I can’t now be sure what approach he tried, and he had probably not ever personally started one of these pumps before, so we soon had a hat trick of dud pumps.
Sailing had to be put back 24 hours. All the Engineers worked 6 on 6 off watches to provide the manpower to strip and repair the three pumps. In the limited space available around the pumps we were virtually working on top of each other, and I was mortified when I hit Jack Warden a mighty blow on his hand with my large hammer. I have always held Jack in the highest regard, having first sailed with him as an Apprentice on Alaric on his first trip as Chief. I think he forgave me, but he never let me forget what pain I had inflicted. Every time we subsequently met he reminded me of how dangerous I was with a big hammer! Indeed, it was mentioned at our very last meeting, at the Southampton Reunion about 10 years ago. Sorry, Jack.
I can’t be sure who was brave enough to start the feed pumps after the repairs, it wasn’t me. The problem was overcome, I think at the end of V2 by simply fitting a small electrically powered pump to provide lubricating water during the start up phase. We live and learn.
_


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## Andrew147

BP "R" boats:-The Coffin pumps had/have a balance piston. If the leak off valve is left shut after doing PM's etc then on starting the moving blades meet the fixed blades, not a noise that can be tolerated longer than 5 sec?. 
I did get it runnin again tho'

BP "P" boats had Weir's TWL's with water lubricated bearings. 

Of the two I think I prefered the Coffin. 
Moral of this story is not to let 2/E start the pump before you've done your final check!


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## Steve Hodges

Andrew147 said:


> BP "P" boats had Weir's TWL's with water lubricated bearings.
> QUOTE]
> 
> "Patience " and "Promise" both had Coffins, Andrew - personal experience prompted me to start this thread - but can't speak for the "Purpose" and "Progress", or the "Pride" if you want to count it in with the other "P"s.
> Or were they changed after I sailed on them?


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## Andrew147

Steve Thinking back, you are right, its a very long time since I left Verolmes on the Patience. A lovely month as a J/E standing by. Which leaves me thinking where did I meet TWL's and the only ship I can think of is the Pioneer, which I think was the only ship BP had from Mitsu.


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## stevekelly10

Andrew147 said:


> Steve Thinking back, you are right, its a very long time since I left Verolmes on the Patience. A lovely month as a J/E standing by. Which leaves me thinking where did I meet TWL's and the only ship I can think of is the Pioneer, which I think was the only ship BP had from Mitsu.


Both the Pioneer and the Surveyor\Shoush had TWL's, both Mitsui built ships. I remember them well!


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## Ginando

We had Coffin feed pumps on several Shell tankers I sailed on. I remember they were really fussy when it came to maintenance, and God help you if you didn't follow the instructions to the letter when it came to servicing any part of them. I remember one of the 2nd's telling me 'If the Coffin book says stop for 10 minutes and have a ***, don't have a coffee and don't go for 15 minutes, smoke a ***, come back 10 minutes later' I didn't argue (well not literally, but I caught his drift). I also had one catch fire, albeit it was small and easily extinguished. That was thanks to someone fitting a copper pipe for the lube oil which blew out at the compression coupling and sprayed oil onto a steam line, so not really the pumps fault.


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## Davidliliequist

Steve Hodges said:


> Some recent correspondence in the BP Shipping forum got onto the subject of Coffin feed pumps, and it turns out that I was not alone in being frightened of the things! I only ever came across them on the BP "P" clas VLCCs built in Holland, but I'm assuming that they must have been pretty common in US built steamers. Was everybody frightened of them?
> From memory, and it's a helluva long time ago, they normally ran at 10,000 rpm and simply screamed like a jet aircraft. The lubrication of the roller bearings was by a high-volume oil wash system. On one ship, one of these oil supply lines was blocked by something ( a bit of PTFE tape I think) and the bearing ran dry. I was on engineroom rounds at the time, heard the normal screaming going decidedly odd, and when I got to it the whole bearing housing was red hot with sparks streaming from it. I thought - briefly - about shutting it down locally, but then I just ran away, to be honest! By the time I got to the control room I think it had seized solid, but we got the electric pump going before we lost everything. If I remember correctly, when it was stripped the bearing inner race had welded itself to the shaft and had to be ground off. The 2/E did get it going again eventually, but we never really trusted it again and used to run the other one all the time.
> The BP Planned Maintenace schedules said that we had to test the overspeed trips on these things something like once a month. The speed governor was hydraulic, so the procedure was to put a lever into the nozzle valve linkage and heave - the speed would shoot up , but the governor would fight back , so you had to heave harder and harder to try to get up to trip speed, which was from ( my now decidely failing) memory around 13,000 rpm. In the meantime, a junior engineer would be kneeling at the end of the unit with a tacho on the end of the shaft. As the speed shot up and the screaming went up several octaves , their nerve would often go and they would just drop the tacho and leg it. I must confess that the overspeed trip test on the PM sheet was frequently falsified!
> It may well be that 35 years have made these memories even more lurid, but I think I can honestly say that Coffin feed pumps were the only things I ever met in an engine room that I was truly frightened of! Anyone else care to confess? Or are US marine engineers a hardier breed?


I also sailed with and overhauled Coffin feed pumps. The special tools required would fill a container. It was a nightmare overhauling one. Compared to Coffins the Wiers Turbine water lubricated or "TWL feed pumps were agreat improvement on high pressure boiler water feed pumps


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