Nick Jones Posted July 3, 2020 Share Posted July 3, 2020 Safe on board and double pay...... the horror. No doubt you’d prefer to be going home....... Link to comment Share on other sites More sharing options...
Escadrille Ecosse Posted July 3, 2020 Share Posted July 3, 2020 Clouds and silver linings! Link to comment Share on other sites More sharing options...
Hamish Posted July 3, 2020 Share Posted July 3, 2020 And I hope tax free as you are out of the country and not really in any other country for that matter !!! Link to comment Share on other sites More sharing options...
thebrookster Posted July 4, 2020 Author Share Posted July 4, 2020 4 hours ago, Hamish said: And I hope tax free as you are out of the country and not really in any other country for that matter !!! Kind off. Technically, I pay tax, it is just that I am assessed as paying zero rate. Comes to the same thing in terms of my bank account, but it is a distinction seafarers insist on now so that we don't get lumped in with all the tax dodgers! Basically, I require 183 days out the UK in the previous 12 months (this is a rolling 12 months, not fixed), and I also have to meet various extra criteria with regard to how long I can be in the country (I can't do 6 months away, then 6 months in for example). I never recall the exact ins and outs, I simply pay a specialist sea tax company to tell me what to do! Given my work/leave ratio is 3/2, I never have an issue. Link to comment Share on other sites More sharing options...
John I Posted July 4, 2020 Share Posted July 4, 2020 5 hours ago, thebrookster said: , I simply pay a specialist sea tax company to tell me what to do! Given my work/leave ratio is 3/2, I never have an issue. Are Sea Tax still going? They use to be very good at telling you when you had to disappear out of the country, this was when the tax man couldn't make up his mind wether it was 183 days or what ever other combination the men in grey suits came up with. Glad to hear that seafarers still get that benefit if they spend so much time away. Enjoy your leave when you finally get there. Link to comment Share on other sites More sharing options...
Hamish Posted July 6, 2020 Share Posted July 6, 2020 That’s One bit of good news at Least. especially as I watched Captain Phillips last night. sorry perhaps I shouldn’t mention it Link to comment Share on other sites More sharing options...
thebrookster Posted July 8, 2020 Author Share Posted July 8, 2020 Well, if you want an idea of how the world's economy is fairing right now, this might give you an idea. We are anchored just outside Singapore/Malaysia doing a repair to a valve in a Cargo tank. Most of the rest of these ships simply have no cargo to carry! This is forward view, there is same again behind, and these are the ones in sight. I estimate a few thousand vessels are waiting here. Apologies for the "wavy" photo, turns out my hand is not as steady as I hoped lol. Cheers Phil Link to comment Share on other sites More sharing options...
Escadrille Ecosse Posted July 8, 2020 Share Posted July 8, 2020 Impressive view, if a slightly depressing thought! Link to comment Share on other sites More sharing options...
thebrookster Posted July 13, 2020 Author Share Posted July 13, 2020 Well, can say one thing for Singapore/Malaysia area, it knows how to rain! Photo doesn't do much justice, but there is over an inch of water on the deck, it and it appeared in about 5 seconds! Looks like next couple of days will involve pulling a piston on the Main Engine, so I shall endeavour to take plenty of photos for y'all!! Phil Link to comment Share on other sites More sharing options...
mpbarrett Posted July 13, 2020 Share Posted July 13, 2020 That looks very wet... Looking forward to your engine rebuild Does it have a single engine, so I guess that means you are stranded until the rebuild is finished? I am surprised you can do that while moored of the coast but I guess if it all goes wrong you can get towed into port? cheers Mike Link to comment Share on other sites More sharing options...
Escadrille Ecosse Posted July 13, 2020 Share Posted July 13, 2020 That's wet! Presumably you're not trying to pump it all out with the wee diaphragm pump Nice they're letting you do the job at anchor with the engine stopped. Even if the humidity is a bit over 100% Looking forward to the pics of the strip down. Why the need for the swap? Colin Link to comment Share on other sites More sharing options...
thebrookster Posted July 13, 2020 Author Share Posted July 13, 2020 14 hours ago, mpbarrett said: That looks very wet... Looking forward to your engine rebuild Does it have a single engine, so I guess that means you are stranded until the rebuild is finished? I am surprised you can do that while moored of the coast but I guess if it all goes wrong you can get towed into port? cheers Mike Mike - only place to do it is anchor! The only times we are alongside normally is for cargo, and drydock every five years. And all oil terminals get very upset if you disable your Main Engine whilst alongside. If anything goes wrong we ship technicians out to us. 14 hours ago, Escadrille Ecosse said: That's wet! Presumably you're not trying to pump it all out with the wee diaphragm pump Nice they're letting you do the job at anchor with the engine stopped. Even if the humidity is a bit over 100% Looking forward to the pics of the strip down. Why the need for the swap? Colin Never tried pulling a piston with the engine running Colin, I think that might be slightly painful Temps are warm, but ok. 37 degrees, and 30% Rel Humidity. Will use a few boilersuits today I guess. Swapping is due to running hours, no other reason. This ship goes back to the owners in January, and they want all major jobs due to be completed before they accept the ship back. We have a down period just now, so good timing. Still waiting for news regarding going home, but Australia is looking less and less likely (finding flights and paperwork apparently), so may be here for the foreseeable future! Should know in the next week or so I hope. Phil Link to comment Share on other sites More sharing options...
thebrookster Posted July 14, 2020 Author Share Posted July 14, 2020 Well, mostly self explanatory, so I shall leave the photos to mostly speak for themselves. Prep of "new" piston yesterday: Started 6am, and had piston out by lunch. (This is what counts as a torque wrench on large engines. The Cylinder Head bolts require a pressure of 1650 Bar to open) (Looks like we caught this one in time!!) (Inside the exhaust valve looking down) Re-hydration is a chore, and the Engine Room is starting to resemble a Laundry Room! I managed 4 boilersuits between 6am and 1130am. Any questions, ask away and I shall endeavour to answer. Phil Link to comment Share on other sites More sharing options...
mpbarrett Posted July 14, 2020 Share Posted July 14, 2020 excellent, very interesting, thanks. I think I need to find a drawing of a Oil Tanker engine.... The connecting rod is interesting, it dosent seem to have a pivot where the gudeon pin should be, just aa long shaft. How does it connect to the crankshaft? I am impressed by the amount of planned maintenance that you do. So often the accountants get to run companies and the first thing that goes is 'unnecessary' planned maintenance until everyone is fire fighting to keep stuff running... mike Link to comment Share on other sites More sharing options...
JohnD Posted July 14, 2020 Share Posted July 14, 2020 This is excellent, Phil, fascinating! I love work, could watch others doing for hours! What is your last pic? Is it the tool used to grip the piston by the crown, to lift it out? And your pics showd the top end - was someone down in the bowels, undoing big ends? Like Mike, I'm unclear about hos that works. JOhn Link to comment Share on other sites More sharing options...
John I Posted July 14, 2020 Share Posted July 14, 2020 That's one large captivated cannon ball and long connecting rod. I bet you were glad that things hadn't been running for a while so the crankcase and head could cool down to some where near ambient temp. Always fascinating to see such large iron work come apart in a controlled manner, not so when its uncontrolled. Link to comment Share on other sites More sharing options...
Escadrille Ecosse Posted July 14, 2020 Share Posted July 14, 2020 Like a normal engine only huuuge. Very impressive. Phil, I wondered about working on the engine when running. I worked with an ex-marine engineer many, many years ago who had served on turbine and diesel ships and he told me they were able to isolate one cylinder of the diesels to carry out major repairs if necessary. Not something you wanted to do but could be done in an emergency, like when broken down half way between Australia and South Africa!! He would have been talking about the 50's through to maybe the early 1970's so I'm not sure things would be the same now. When I did my Engineering degree we still had to learn how to calculate the energy cycles for steam (and gas) turbines in thermodynamics (impulse and reaction types!) because of the marine link. Other than the nuclear submarines are turbines still used in ships? Questions Is it a two stroke or a four stroke? What are the pistons made from? Do you have a really big ring compressor to get the rings in? If that's the conrod how tall is the engine and what is the stroke, must be enormous. Sure we'll all think of more to ask Colin Link to comment Share on other sites More sharing options...
thebrookster Posted July 14, 2020 Author Share Posted July 14, 2020 2 hours ago, mpbarrett said: excellent, very interesting, thanks. I think I need to find a drawing of a Oil Tanker engine.... The connecting rod is interesting, it dosent seem to have a pivot where the gudeon pin should be, just aa long shaft. How does it connect to the crankshaft? I am impressed by the amount of planned maintenance that you do. So often the accountants get to run companies and the first thing that goes is 'unnecessary' planned maintenance until everyone is fire fighting to keep stuff running... mike That's the Piston Rod, as this is a large two stroke it has two rods, the piston and the connecting. Think of it in terms of stroke, which here is 2.4 metres. Then think of the swing on the crank to get that stroke, on a standard setup the bore of the liner would have to be ridiculous! So instead all the swinging parts are inside the crankcase. Additionally, being a two stroke the intake port is at the bottom of the liner (actually we call it the scavenge port). This needs to be separate from the crankcase, (hot combustion gases come backwards as well as forwards and these tend react a bit precipitately with LO) so again almost impossible to do on a standard engine design. We have to do planned maintenance, this is a requirement of the classification society and we get inspected several times a year to ensure that we do it! To not do it would result in an immediate arrest of the ship, and if the authorities consider the vessel dangerous the Captain and Chief Engineer will also be arrested. (That's not set in stone however, if you have a good reason to postpone a job common sense does prevail!) 1 Link to comment Share on other sites More sharing options...
thebrookster Posted July 14, 2020 Author Share Posted July 14, 2020 2 hours ago, JohnD said: This is excellent, Phil, fascinating! I love work, could watch others doing for hours! What is your last pic? Is it the tool used to grip the piston by the crown, to lift it out? And your pics showd the top end - was someone down in the bowels, undoing big ends? Like Mike, I'm unclear about hos that works. JOhn Nope, that's the piston crown template. The bits you see daylight is where the crown has burnt away over time. And yes, there was an engineer down below. I shall try and get some pics of that side as well. Link to comment Share on other sites More sharing options...
thebrookster Posted July 14, 2020 Author Share Posted July 14, 2020 4 hours ago, Escadrille Ecosse said: Like a normal engine only huuuge. Very impressive. Phil, I wondered about working on the engine when running. I worked with an ex-marine engineer many, many years ago who had served on turbine and diesel ships and he told me they were able to isolate one cylinder of the diesels to carry out major repairs if necessary. Not something you wanted to do but could be done in an emergency, like when broken down half way between Australia and South Africa!! He would have been talking about the 50's through to maybe the early 1970's so I'm not sure things would be the same now. When I did my Engineering degree we still had to learn how to calculate the energy cycles for steam (and gas) turbines in thermodynamics (impulse and reaction types!) because of the marine link. Other than the nuclear submarines are turbines still used in ships? Colin Ahh, okay. Depends on what you term "major repair", but pulling a piston requires the engine to be stopped. Any large slow speed two-stroke (definition of slow speed in engine terms is anything below 200rpm) is designed and built in bits. Various reasons, but namely makes them easier to build. This means that every cylinder has its own fuel pump and exhaust actuator. Each pump has the ability to be locked in the top position, thereby not pumping fuel and disabling that unit. This would allow you to remove a fuel pump or replace injectors if needed, but that is all. And in fact, you still need to stop the engine to lock the pump out! There is also methods by which we can "hang" a piston, disconnected from the Conrod that also takes that cylinder out of action, but if you reach that stage most likely the damage is of more serious levels, and you would be heading for the nearest safe anchorage where the specialist technicians can come onboard. In terms of turbines, steam is still used, primarily for LNG ships. This is a dieing technology however, as a good modern diesel is now more efficient (turbines being very efficient beats, the boilers making the steam not so much). Gas turbines almost extinct. LNG still uses steam because it is easy to burn boil-off gas in a boiler, however both Wartsila and MAN have 2 stroke and 4 stroke engines capable of running on gas, so again steam is going. I only have a motor ticket, so my steam knowledge is limited. I probably will never sail with anything higher than about 20 Bar steam system. Phil 1 Link to comment Share on other sites More sharing options...
thebrookster Posted July 14, 2020 Author Share Posted July 14, 2020 More pictures. We finished this evening at 2015, after a successful test run of the engine. How to measure your liner. This is the cheating method, but bloody good!! Brace across the top, and the measuring tool is set for 600mm (nominal bore size). Simply lower down and take measurement at correct point (easy to judge, at the bottom of the pic you can see the wire going down, this has metal tube crimped on at the right places). Then read the dial! Though you might be slightly shocked to realise this liner is reasonable shape, max wear is about 2.5mm!! Piston rod foot, fastened to top of conrod. You can see the flat the foot is on, the rest is what you might term the "gudgeon pin". This is what the top of the Conrod is fastened to, called the crosshead bearing. This converts the rotary movement of the crank/Conrod to linear. Bottom of Conrod (piston is almost BDC). Bottom, then top of "stuffing box". This is what separates the crankcase from the scavenge space. Brass scrapers, held in place by springs. Phil Link to comment Share on other sites More sharing options...
Escadrille Ecosse Posted July 14, 2020 Share Posted July 14, 2020 Great photos Phil, thanks. Explains the split con-rod arrangement. I like the bore-mic. 2.5mm allowable wear is something! I wondered about separating the crankcase from under the piston. I made model aeroplanes when I was young, powered by small 2-stroke compression ignition engines. Technically not diesels as the compression ratio was adjustable as well as the fueling. Fuel/air got sucked in through the crankcase with the fuel carrying the caster oil lubricant and a shot of neat ether to start them. Only 1cc capacity so a wee bit smaller than your monster. Pretty fast job done too. Link to comment Share on other sites More sharing options...
Nick Jones Posted July 14, 2020 Share Posted July 14, 2020 Ok...... so that is one despatched impressively fast..... but how many cylinders does this thing have? When are you doing the rest and if not, why is this cylinder special? Great pics btw 1 hour ago, Escadrille Ecosse said: I like the bore-mic. 2.5mm allowable wear is something! Does seem like a fair bit..... but the piston is a bit of a beast and as a proportion of diameter it's probably not that much different to "our" engines.... Link to comment Share on other sites More sharing options...
thebrookster Posted July 16, 2020 Author Share Posted July 16, 2020 On 7/15/2020 at 2:50 AM, Nick Jones said: Ok...... so that is one despatched impressively fast..... but how many cylinders does this thing have? When are you doing the rest and if not, why is this cylinder special? Great pics btw Does seem like a fair bit..... but the piston is a bit of a beast and as a proportion of diameter it's probably not that much different to "our" engines.... Just this piston Nick. Although the engine starts with the same running hours on each unit, the stresses and forces involved in something this big means that breakage is not unusual, and normally is the piston rings. With something this size, if you need to replace one ring you might as well do the full overhaul on that unit. This tends to throw all the service intervals out of sync over time. We actually try to stagger intervals anyway, in order to spread the cost over a couple of years. The four rings for each piston are in the region of $4000, so if you do 6 of those, plus the new stuffing box rings and all the other odds and sods, it adds up to fair chunk of cash. Then when you look at it from the office point of view, nearly 20 ships and most of them with bigger engines than this one, it is quite a significant expense. Liner wear - 2.5mm is the lower end of max wear! Generally we are more concerned with ovality, the liners tend to wear more on the port-starboard axis than the forward-aft, and this normally is what dictates replacement. If the wear is equal, we can run up to 4.8mm wear! As a side note, I thought I would give you guys some weights. Piston (+rod) = 1200kg Cyl Head & Exhaust Valve = 2900kg Always gets me, that one piston is the same weight as an average car! Phil 1 Link to comment Share on other sites More sharing options...
PeteStupps Posted July 21, 2020 Share Posted July 21, 2020 On 7/16/2020 at 3:17 PM, thebrookster said: Always gets me, that one piston is the same weight as an average car! Forgive my ignorance but how do you start the thing?? Need a big old starter motor to get those pistons moving... Great photos Phil, fascinating stuff. Link to comment Share on other sites More sharing options...
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