Specific applications include bushings, spacers, bearings and other mechanical parts in automobiles, trucks, aircraft and construction, agricultural and drilling equipment, as well as hydraulic cylinders. Our products offer good dimensional accuracy; good surface quality; excellent micro-structure uniformity; good machinability; and high tensile properties. Cold drawn seamless tubing is also suited for such post-treatments as carburizing and heat treating.
Cold drawn seamless mechanical tubing is used in a variety of uses, particularly when heavy wall thicknesses, specific steel alloys or both are required.
Features
- Dimensional accuracy
- Enhanced outside diameter (OD) and inside diameter (ID) surface quality
Benefits
- Wide range of applications
- High strength-to weight ratio
- Excellent machinability
- Improved tool life
- Reduced raw material requirements
- Reduced machining time and expense
Capabilities
OD | Wall |
---|---|
1.375 – 7.750" | 0.188 - 1.718" |
Size capability may vary by specification and facility. Please inquire for more specific information.
Grades
Type or spec | Grade |
---|---|
Carbon base grades | 1008 – 1050 |
Alloy full range of 41xx/43xx & 86xx series |
Others available by inquiry
Specifications
- ASTM A519
- Customer specific available by inquiry & review
Manufacturing process
Tubular Products’ seamless mechanical tubing is produced from solid round billets by rotary piercing and then rolled in an Assel mill that permits an extremely broad range of diameter/wall thickness ratios. Tubes are then processed through a multiple-pass size reducing mill and a rotary sizer.
Tube lengths from the hot mill are slowly air cooled or moved directly to a unique isothermal annealing furnace to ensure a uniform microstructure hardness to promote excellent machinability. This process contrasts with conventional slow-cool furnaces, where tubes are cooled in bundles. That can result in variations in microstructure and hardness from tube to tube and even within a tube itself.
After cooling, tubes are pickled in an acid bath to remove mill scale and inspected. Minor imperfections are removed by grinding prior to cold drawing and additional processing. During the cold drawing process, tubes are drawn in a controlled fashion over a mandrel and through a die to reduce the diameter and wall thickness. After forming and depending on customer requirements, the tubing is stress relief annealed, straightened and cut to length. Tubes are inspected for dimensional accuracy and surface finish.
Cold working, applied to both inside and outside surfaces, improves surface finish, increases tensile properties, improves machinability in many grades and results in more precise dimensions. Outside diameter and wall thickness tolerance are improved by approximately 50 percent.