High Performance Billet 4340 Steel Cranks for BMW M50 E34 520i E36 320i M50B20 Racing Crankshaft

Product Overview

Description

High Performance Billet 4340 Steel Cranks for BMW M50 E34 520i E36 320i M50B20 Racing Crankshaft

      

 

 Quick Detail

 

Material	Full CNC 4340 Billet Steel
Date of Delivery	5-7 days if in stock,80-90 days if out of stock
Application	for BMW E34 E36 M50 M50B25 Crankshaft

 

 

     Dimension

 

 

Main Journal Diameter	***mm
Rod Journal	***mm
Stroke	Original or customized
Net Weight	***kg
Length	***mm

 

 

 

NLGROUP  DESIGN  

 

 

customized design counterweight                        Pendulum Undercut Counterweight

 

   

 

Knife Edge Counterweights                                      Oil Groove Counterweights

 

     

 

Knife Edge Counterweights                                   Tapered Counterweights

 

       

 

Lighten Holes at Rod Journals                                           

 

 

 

 

Technical Features

 

 

• Materials:40CrNiMoA  Heating treatment:HRC34-38

• Crankshaft will get thermal refining after normalizing,HRC34-38.The difference will be within 4HRC on same one cranks

 

• No over burning,carbon-free surface layer is within 0.3mm 

 

• Folding,oilet,cracks, oxidation and other things is not permitted for Cranks macrostructure.

• Balance weight value need keep 0-20g.cm on counterweight of big end and small end

 

• Peening treatment will be done after balance weight 

• Nitrogen treatment will be done after precision grind,compound layer depth is 0.008mm after polishing.diffusion layer is over 0.3mm,hardness on surface is not less than 500HV.

• No damage,scallops and other visible disadvantage on surface.

 

• Crankshaft will be cleaned up to make sure there is no filings in oil hole.

 

• magnetic flaw detecting will be done according to standard JB/76729-93

 

• Other size tolerance :standdars GB1804-79  IT14,No marked place  roughness:Ra6.3

 

 

Processing & Packaging

 

 

 

 

 

 

 

 Tips: Our whole product line is not here, if you do not find what you need, pls feel free to contact us for more.