Custom CNC Machining & Heat Treatment Services of Heavy Duty Bushings

At Blue Grass Manufacturing Co. of Lexington Inc., we are adept at working with unique customer specifications to develop custom manufacturing methods based on our ISO 9001:2008 certification and Six Sigma training. This contract manufacturing project was brought to us by a customer in the heavy construction equipment industry. These heavy duty bushings are machined from hardened and tempered medium carbon steel and have an outer diameter of 8" with a length of 4". The heat treated bushings are turned and milled to tolerances of ±0.001" and are required to have a surface finish of 0.5 µm Ra or better. In addition, per customer specifications, no chemical or rust preventatives could be used on the metal surface.

We developed custom runout gauges, for this project in addition to the precision bore gauges and micrometers used to take part dimensions. The bushings are also measured on our Zeiss CMM at each step of the manufacturing process to verify part conformance. After production and inspection the bushings are specially packaged for delivery. We manufacture 150 to 650 of these parts per month with a typical lead time of two weeks per production run. For additional details regarding this precision machining project, see the table below, or contact us directly.

Family of Heavy Duty Bearing Housings Project Highlights

Product Description
Family of heavy duty bushing
Capabilities Applied/Processes
Primary Services:
  • Saw Cutting
  • Heat Treatment
  • Turning
  • Milling
  • Packaging
Equipment Used to Manufacture Heavy Duty Bushings
Lathes and Mills
Overall Heavy Duty Bushing Dimensions
Outer Diameter: 8" (203 mm)
Length: 4" (102 mm)
Weight: ≤ 50 lbs.
Tightest Tolerances
Material Used
Hardened and tempered medium carbon steel
Material Finish
Surface finish better than 0.5µm Ra
Additional Facts
No chemicals and rust preventatives permitted on surface
In Process Testing/Inspection Performed
Custom made runout gages, micrometers, precision bore gages, CMM inspection at EACH process step using Zeiss Contura G2 CMM
Industry for Use
Heavy construction equipment
150 to 650 per month
Delivery/Turnaround Time
Typically 2 weeks
Delivery Location
75 Miles
Standards Met
A number of Customer Specifications concerning metallurgical purity, heat treatment, surface finish, defects, roundness and packaging, 3D CAD Drawing