Crankshaft Machining

Previously part machined by competitor & abandoned
In-Situ picked up the pieces & this is the end result
Peen straightening a bent shaft
End result after removing 17mm on Ø
Machining by tooling method (not grinding). For fast stock removal
Blackstone K Major machined back to
makers standards
Setting false ring with
computerised levels at
sea due to damaged fillet radii
  
Machining in progress on heat affected pin, distinguished by the shiny areas
Superfinishing operation in progress
Crack detection by Magnaflux
Inspection using Equotip to detect hardness
Damaged Ø and keyway of a timing gear journal
Machining of journal Ø in progress
Milling of new keyway
Completed Ø and keyway
Grinding of main bearing journal
Finished journal back
to standard

CRANKPIN REPAIRS

  • Full range of equipment for Orbital machining, superfinishing and polishing journals in the range 100mm to 1075mm in diameter
     

  • Shaft straightening can also be performed using the OEM recognised method of Peene straightening
     

  • Quality in accordance with OEM tolerances, i.e. for Crankshaft Journals 0.15mm/metre straightness to shaft axis, 0.02mm roundness and parallel. Surface finish better than 0.2µm Ra

CRANKPIN MACHINING PROCESS

In the event of Fillet Radii damage & hard spots caused by a severe seizure      

1 Mask area/Plug oil holes to prevent contamination
   
2a Take Measurements and record  
2b Hardness/MPI check and record
2c Grind hard spots to establish depth and record 
2d Determine final target size with recorded information
   
3a Fit False Ring and set with computerised levels 
3b Install Orbital machine and frequency controlled motor
3c Recut damaged Fillet radii  
3d Remove Orbital machine and False Ring
   
4 Re-Install Orbital machine
   
5 Machine Crankpin diameter
   
6 Re-check hardness and MPI to verify final target size is obtainable
   
7 Machine Fillet radii
   
8 Polish Fillet radii
   
9 Polish Oil hole radii
   
10 Superfinish Crankpin diameter
   
11 Polish Crankpin diameter
   
12 Remove Orbital machine
   
13 Clean area
   
14 Remove masking/plugs for oil holes
   
15 Take final measurements/record and sign off
   

CRANKPIN CONTROL METHODS

  • Axis tolerances achieved by electronically controlled level system        

  • Diameter controlled by calibrated micrometer, measured and recorded   

  • Flatness controlled by engineers' blue and straight edges

  • Crack detection via Magnetic Particle Inspection system 

  • Hardness checked using portable electronic device

  • All data recorded