Crankcase inspection on ship is an important task or regular check to be done. As name suggest, it is the area where crankcase is fitted or located. In this article we will focus on the checks that you need to carry out while doing the crankcase inspection.
Crankcase is the space where you have your crankshaft, main bearings, crankpin bearing, crosshead bearing, crosshead guide and stuffing box. Now the questions arises as why need to do the checks. Well just like other machineries, all the parts mentioned are in motion and can have issues resulting due to lubrication or vibrations. Below are the checks that you need to carry out while doing the inspection. This article is useful for the junior officers who would like to get an insight as what we are supposed to check inside.
You might like to read this article as well: Checks needs to be done in a scavenge space of a ship
Crankcase Inspection On Ship: What to check
Following are the checks that need to be carried out and it is suitable for both SULZER and MAN engines.
1) Prior to the inspection, open the crankcase doors and ventilate the space properly. Switch of the breaker of the lubrication pumps. Engage the turning gear as well.
2) For safety purposes, remove all the items in your pocket and wear safety harness. At all times, one person should be standing outside the crankcase doors. You might like to wear anti slippery shoes.
3) Go to down the ladder inside the crankcase space and move in a manner like a duck to avoid your head hitting the metal.
4) On the bottom part try to see for any metal particles (white). Also check for any sign of deterioration of lubrication oil or any kind of localized heating or heat mark.
5) Using flash light you can see the condition of main bearing from outside as any sign of metal particles coming out.
6) Check same for the crankpin bearing as well.
7) Check for any kind of corrosion taking place on the webs or the crank pin surfaces.
8) Now move up and with a plastic hammer slightly tap the hydraulic nuts on the crankpin or the crosshead bearing. This is just to check if they are tight and have not loosened over the time due to the vibration taking place. If any nut is loose, you will be to find it with different noise it makes when hit by a soft hammer.
9) Check crosshead bearing for any kind of marks or metal coming out.
10)Note: It is a good idea to stand on the crosshead and go up to check the stuffing box in MAN engines. You just need to put your harness and slowly you can go up. Person standing outside can move the crankshaft using the turning gear and keeping an eye on your position.
11)During going up, you can have a look at the crosshead guide surfaces, piston rod surfaces and stuffing box holding bolts.
12)Any scratches on the piston rod, is a sign of improper lubrication and too much tightness of the stuffing box rings.
13)Also check for the other additional nuts that are present like piston foot and other small nuts and bolts.
14)Check the passage for Oil mist detector is clean.
15)Make sure to take the pictures for future references.
16)Move out safely and secure the doors of the crankcase.
These were the checks that you need to carry out in crankcase inspection on ship. It is always advised to do the work in a safe manner as the surfaces inside are slippery and safety precautions to be carried out always.