MAN Diesel Generator Model no. 9L28/32

About MAN Diesel Generator Model no. 9L28/32

RA Power Solutions was approached by a company based in Dubai regarding a problem in crankshaft faced in MAN Diesel Generating set model no. 9L28/32.

The make, model of Engine and crankshaft details are given below:

S. NO	Crankshaft Details
1	Engine Make	MAN B&W
2	Engine Model	9L28/32
3	Crankpin Diameter Standard	230 mm
4	Crankpin Bearing Width	98 mm
5	Place of execution of crankshaft repair	Sailing from Port of Jebel Ali Dubai to JNPT port India

Repair of MAN Engine Model no. 9L28/32 Diesel Generating set Crankshaft

RA Power Solutions deputed two technicians along with an onsite crankshaft grinding machine and technicians boarded the vessel at port of Jebel Ali Dubai. On conducting the inspection following are the main observations of the crankshaft of MAN Engine Model no. 9L28/32 diesel Generating sets.

i) It was observed that the crankpin no. 3 of the AE#02 was damaged. The Bearing material was embedded on the crankpin diameter. After removal of the white metal from the crankpin, the dimension inspection was done and following was observed:

    a) Minimum crankpin diameter observed:  229.44 mm

   b) Maximum crankpin diameter observed:  229.83 mm

The above readings were observed against the standard diameter of 230.00 mm.    

ii)The radius fillet and lubricating oil hole profiles were found acceptable with no damage.

iii) Deep Bearings line marks were observed on the remaining 8 numbers of crankpins. 

iv) All the crankpins were subject to hardness test and crack check by MPI method and no abnormality was observed.

v) All other parameters were observed within limits. 

Successful Crankshaft Repair of MAN Engine Model no. 9L28/32

i) The grinding of crankpin no. 3 was initially undertaken to the undersize of 1.0 mm maintaining the crankpin diameter of  229.00 mm. Since the Bearing line marks were still visible it was decided to grind further. The final size maintained after grinding and polishing was 228.50 mm which is 1.5 mm undersize. 

ii) Considering the rough surface finish and bearing line marks all the remaining crankpins were polished while using the state of art crankshaft grinding & polishing machine using the latest polishing media. 

iii) The surface finish of less than 0.20 RA value was maintained. 

iv) The ship had the 1.5 mm undersize bearing available which was assembled and the engine was put on load.

Exceptional Performance and Efficiency

Engineered to produce up to 3000 kW at 720 rpm, the MAN 9L28/32 diesel generator stands out with its high efficiency and reduced specific fuel consumption (~187 g/kWh). The direct injection system and electronic governor ensure optimal combustion and efficient load response, making it a reliable choice for sectors that demand consistent and powerful energy supply.


Built for Demanding Environments

Crafted from high-grade cast iron and steel, the MAN 9L28/32's robust construction, anti-corrosive coating, and heavy-duty engine walls provide maximum durability. This generator is ideal for rigorous settings such as marine vessels, industrial facilities, and power plants. Its water-cooled, forced lubrication system extends service life, minimizing downtime and maintenance.


Advanced Features and Compliance

Equipped with a brushless synchronous alternator, the generator is capable of delivering up to 11 kV as per configuration. It meets IMO Tier II emission standards, ensuring environmental compliance. The versatile design allows for electric or compressed air starting, and optional wet or dry exhaust systems accommodate a range of installation requirements.