Shaft-lin haft-line e and Main Main Engine Engi ne ali alignm gnme ent onbo o nboa ard
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
To obtain optimal parameters for service conditions
Engine crankshaft straight in service condition
Bearing load of all main engine bearings and propeller line in service condition to be within specified limits
Acceptable crankshaft deflections in service condition
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
To compensate as much as possible changes between alignment and service condition: a) Hull deflection b) Engine temperature c) Dry dock / afloat
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
Cold, aligning aligning conditio ns
Service rvi ce conditio cond itions ns
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
Initial SAG of b edpla dpl ate appl applied ied
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board MAN Diesel, recommended main engine alignment before chocking (afloat condition, coupled to shafting system and main engine in sagged condition).
Recommended procedure:
At present present MAN Diesel Diesel recommended recommended procedure prior prior to chocking chocking is: • Vesse essell in in afl afloa oatt con condi diti tion on • Engine Engine in sagged sagged condition condition (piano (piano wire wire verific verificatio ation). n). • Engine Engine coupled coupled to the shafti shafting ng system. system. That That is to contro controll the cranksha crankshaft ft deflecti deflection on of the last unit and the engine aft end static load. • Engine cold.
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
Coupling of main engine with shaft line to be performed according to shaft calculation, SAG and GAP for the flange coupling between intermediate shaft / engine crankshaft. After coupling, before chocking, one complete set of measurements should be recorded in order to confirm the main engine alignment. MAN Diesel & Turbo can provide the Excel format for the measurements and review the measurements all free of charge on request. Ref. MAN B&W Quality Specification No. 0743547-3 Ref. MAN B&W Production Recommendation No. 0743104-0
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
1. Shaft Shaft line li ne ali align gnment ment proc pr ocedur edure, e, SAG / GAP
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
Measurement Measurement of GAP/SAG GAP/SAG for fl ange cou pli ng Main Main Engine / Int ermediate ermediate Shaft
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
2. Measur Measurement ement of Main Main Engine Engi ne SAG SAG by piano pi ano wir w ire e
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board Piano-wi Piano-wi re too l-set
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
Example of excel sheet chart for SAG measurements
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
3. Measurin su ring g of t he cranksh cr anksha aft de d eflection flect ion (autolog uto log)) (Ref. MAN B&W Quality Specification No. 0743503-0)
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board 4. Bearing Bearing Loads Checking of bearing load (reaction) by jacking-up test at cold condition, for the shaft line bearing(s) and for the three aftmost engine bearings. (Ref. MAN B&W Production Recommendation 0742884-5)
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board Jack-up measur measureme ements nts of interme int ermediate diate shaft shaft bearing bearing load
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board Dial Dial gauge g auge for m easurements easurements of intermediate shaft shaft bearing bearing load
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board Jack-up measurements measurements of main bearing bearing load
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board Dial Dial gauge g auge for measurements measurements of main bearing l oad
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board 5. Ma Main beari bearing ng top to p cle cl earance In some cases (e.g VLCC’s) 0.2 mm reduction of the top clearance in aftmost engine bearing is acceptable at the alignment (light, afloat) condition.
Feeler Gauge
Measurement of main bearing top clearance by feeler gauge
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board Main Main engine align alignment ment di agram – step by step
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
MDT recommend: Checking the alignment in way of Crankshaft
deflection Bearing load Engine SAG Main Bearing clearance - before chocking the engine
Shaft-lin haft-line e and Main Main Engine Engi ne ali align gnment ment onboard on board
Tha hank nk yo you u very much for your attention!
