In Situ Crankshaft Repair Using Portable In Situ Crankshaft Grinding Machine
We Carry Out Crankshaft Grinding Where the Engine is Installed
After spending years attending crankshaft failures on board vessels and at industrial plants, we've found that removing a crankshaft is often the biggest contributor to repair time and cost. On most vessels, particularly during an unscheduled breakdown, dismantling the engine, lifting the shaft, arranging transport, and reassembling everything can keep the vessel off hire far longer than the actual machining work.
For this reason, we regularly perform in situ crankshaft grinding directly inside the engine block. Our portable crankshaft grinding machine is designed for operation through the engine inspection window, allowing us to restore damaged crankpins without removing the crankshaft from the engine.
The machine accommodates crankshaft diameters ranging from 35 mm to 700 mm, covering the majority of auxiliary engine and main engine crankshafts encountered in marine and industrial applications.
Insitu Crankshaft Grinding, Polishing Machine
Portable Design for Limited Working Space
Anyone who has worked inside an engine room knows that available space is always limited. We designed our onsite crankshaft grinding machine to be compact enough for installation inside confined engine spaces while maintaining the rigidity required for accurate machining.
Whether the repair is carried out alongside, at anchorage, or during dry dock, the equipment can be installed directly on the engine block without removing the crankshaft from the engine or press.
Why We Prefer In Situ Crankshaft Grinding
From practical experience, onsite machining offers several operational advantages.
No Crankshaft Removal Required
We perform grinding with the crankshaft remaining in position inside the engine. This eliminates dismantling of the engine structure, avoids heavy lifting arrangements, and removes the need for transporting the crankshaft to a workshop.
Reduced Vessel Downtime
In many cases, depending on the extent of damage and inspection results, some crankshaft repairs can be completed in as little as 24 hours.
This makes a significant difference when a vessel is waiting for repairs before returning to service.
Lower Repair Cost
Keeping the crankshaft inside the engine avoids the cost of complete engine strip-down, transportation, workshop machining, and reassembly.
From our field work, these savings are usually substantial, particularly on medium-speed and slow-speed marine engines.
Grinding to OEM Requirements
During crankpin machining we monitor the following:
- Crankpin diameter
- Ovality
- Taper
- Fillet radius protection
- OEM regrind limits
- Surface finish
The crankpins are machined to OEM tolerances and surface finish specifications to ensure proper hydrodynamic lubrication after assembly.
Where required, repair dimensions are verified in accordance with OEM recommendations and classification society requirements, including DNV, ABS, and Lloyd's, whenever applicable.
Crankshaft Polishing
Where damage is limited to light scoring or minor surface imperfections, complete grinding may not be necessary.
In these cases, we carry out crankshaft polishing to restore the journal surface. The polishing process can improve the crankpin finish to 0.2 micron Ra, helping restore the surface required for reliable bearing performance.
Crankshaft Capacity
Our portable onsite crankshaft grinding machine covers standard crankshaft diameters from:
- 35 mm to 700 mm
This capacity allows us to repair most auxiliary engine and main engine crankshafts without removing the shaft from the engine.
Typical Applications
We regularly use our in situ crankshaft grinding machine for:
- Marine main engine crankshafts
- Auxiliary engine crankshafts
- Diesel generator crankshafts
- Compressor crankshafts
- Pump crankshafts
- Industrial engine crankshafts
- Power plant engines
If you require in situ crankshaft grinding, portable crankshaft grinding, or crankshaft polishing, we can review the damage report and recommend the appropriate repair procedure based on OEM limits and the operating condition of the engine.
Email: rajshahani@rapowersolutions.com
Email: info@rapowersolutions.com
Phone: +91 9582647131 | +91 9810012383