Air cooler C 28-1/6. Tools : (The construction varies depending on extracting tool)

Transcription

1 Air cooler Structure Horizontal-type Remark): There are 2 types of air cooler that are equipped with and without feed water heater. 6 Tools : (The construction varies depending on extracting tool) 1 Roller plate Each 1 Distance piece 94662a, 94662b, 94662c Each 1 Dismantling and assembling device 94663a, 94663b, 94663c 1 Rail No. Name of article Check item 1 Element Take care about broken 2 Tube sheet 3 Header Coated inside to (In / out side) prevent damage. 4 Header Ditto 5 Side plate 6 Side plate C 28-1/6

2 1-1 Air cooler list No. Eng. Eng.Type Air Cooler Ship Yard Ship No. No. Manufacturer Type No. Heater RTA96C IHI Kure 3086 Suction Gas Engine SWPX-979F/R190A/4 96-A601&A602, Mfg. Co., Ltd. A614&A615 Without RTA96C IHI Kure A267&A270, A269&A RTA96C IHI-MU Kure 3088 SWPX-1586F/R190A/4 97-A363~A RTA96C IHI-MU Kure A514~A RTA96C IHI-MU Kure A645~A RTA96C IHI-MU Kure A075~A RTA96C IHI-MU Kure 3151 CH4F-2293F/R204B/4 01-A208~A210 With RTA96C IHI-MU Kure A283~A RTA96C IHI-MU Kure A351~A RTA96C Koyo 2135 CH6S-1556F/R204B/4 01-A409~A411 Without RTA96C Koyo A451~A RTA96C IHI-MU Kure 3155 CH6S-1945F/R240B/4 02-A037~A RTA96C IHI-MU Kure A152~A RTA96C IHI-MU Kure A178~A RTA96C IHI-MU Kure A272~A RTA96C IHI-MU Yokohama 3163 CH4F-2165F/R240B/4 02-A072~A074 With RTA96C IHI-MU Yokohama A218~A RTA96C IHI-MU Yokohama A353~A RTA96C IHI-MU Yokohama A112~A RTA96C IHI-MU Kure 3167 CH6S-1945F/R240B/4 03-A071~A073 Without RTA96C IHI-MU Kure A128~A RTA96C IHI-MU Kure A264~A RTA96C Koyo 2147 CH6S-1849F/R240B/4 02-A292~A RTA96C Koyo 2148 同上 03-A027~A029 96C 28-2/6

3 1-2 Outline of structure The feature of air cooler for RTA84T type engine is as follows. Flow direction of scavenging air: Air passage in horizontal (left and right) direction (Vertical-type air cooler) Less channeling in tubes even in small quantity of water Feed water heater: With or without heater. Main engine can be run without supply of feed water. Cooling medium: Fresh water 2. Check item 2-1 Periodic checks At time of engine patrol 1) Check the jointing face of casing (inlet side) and air-duct for leakage of scavenging air. (Caution: Be cautions about the scavenging temperature that normally it reaches higher than 140 C.) Measures: Tighten the bolts. Change packing during repair at the dock. 2) Ensure that a small amount of fresh water flows all the time from the air vent. 3) Check the scavenging differential pressure before and after air cooler (the degree of element contamination). 4) Check the gasket and connecting pipe flange in the cooling water chest for leakage of fresh water. 5) If drain from the air duct increase suddenly, the tube of air cooler is in danger of being broken. 96C 28-3/6

4 2-2 Cautions in operation 1) When freshwater is leaking from a broken tube, provide blind plugs in the broken tube, as soon as possible. At the same time, check the inside of the scavenging-space. 2) Carry out the air vent for water line of air cooler at delivery from the port and at checking of M0 system Prevent remaining the air in these lines. (In case of no apply the continuous air vent line) 3) Always confirm the tendency of differential pressure between air cooler inlet air pressure to outlet one, which is measured by manometer, in order to prevent contamination and blockage of cooler airside. 4) Take care not to damage rust-preventive coating (neoprene, hyperons, tar-epoxy and etc.) of the inner face of header. And any damage is discovered, repair it without delay. 5) When stopping the engine for a long period, drain cooling fresh water inside air cooler. Inspection of painting / coating : 1 time / year 2-3 Maintenance at dock 1) As standard at the repair-dock in service, also considering the maintenance results of the air-coolers, to be unloaded this air-cooler and carried out overhauling and cleaning. At this chance, carry out the cleaning / inspection of both cooling water side and air side, also pressure test the leakage of cooling waterside. 2) In the case that the erosion of cavitations etc. was discovered on the inlet side of cooling pipe with the inspection of the air cooler, insert the insertion tube (in case of round tube) in order to prevent the erosion of cavitations etc. 96C 28-4/6

5 2-4 Investigation of air cooler renewal 1) Grasp the condition of air cooler by periodic maintenance / inspection. 2) Make a proper maintenance plan according to the above conditions of the air cooler. In the case that the operation point is not able to obtain the cooling ability of requiring in a short time in spite of after maintenance, consider renewal of the air cooler. 3. Overhaul / reassembly 1) Retightening the bolts when scavenging air leakage happens. Just after overhaul and reassembly, air leak used to occur. 2) Replace the gasket and O-ring by new ones when the header is overhauled. And tighten the bolt clockwise (in the order of 12:00-6:00-3:00-9:00 of clock) 3) Ensure that there are no paint and oil sticking to the surface of protective metal and threads. 3-1 Cleaning on air side Judging criterion for cleaning: To be cleaned before the maximum differential pressure reaches 300mm Aq. Cleaning method: 1) Cleaning by compressed air 2) Cleaning by steam Remove oil contaminated stuff with steam (3 ~ 7 kg/cm², 150 C) 3) Chemical cleaning (consult with the cleaning maker.) When airside is washed by the chemicals, the stain of the upper tube falls to the lower tube by an insufficient washing, then the stain accumulates, and sometimes causes the blockage in the airside. Never heat the cleaning agent higher than 75 C. The cleaning time differs depending on the type of cleaning agent and the condition of dirt. After cleaning is finished, wash the tubes with fresh water to neutralize them. Confirm that the airside is not choked. 96C 28-5/6

6 3-2 Cleaning on water side In case of freshwater cooling, periodically inspect the inside of cooler and wash the cooler if necessary, although there is not the fear of the tube blockade by salt accumulation etc. like seawater cooling. 4. Failure sample 1) Inflow of the cooling water into the scavenging-space due to broken holes of air cooler 2) Water and air leakage due to aging of o-rings and gaskets 5. Technical information Service information DUQ1-059E Preventing maintenance against clogging of scavenge air cooler 96C 28-6/6