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As the material will be plastically deformed by pressure, it should have a minimum elongation of 5% and a maximum tensile strength of 246,000 PSI.

Materials that have less than 5%

Elongation or a significant hardness greater than 40 HRC, such as cast iron, hard brass alloys, and other hardened materials, are not suitable candidates for the thread rolling process.

The only requirement for the rolling process is that either the component or the rolling head, or both, is rotating toward the other.

Thread rolling tools can be used on a wide variety of standard and special machine tools:

• CNC and Manual Lathes
• Screw Machines
• Many Types of Special Machines
• Transfer Machines
• Rotating and In-line Machines
• Drilling and Tapping Machines

Threads are produced in seconds and in only one (1) pass, whereas CNC single-point thread cutting requires numerous passes and a much longer cycle time. Long roll life eliminates costly downtime for tool changes.

In cold forming operations, extremely short cycle times are not just a welcome attribute but rather a condition of the process. In plastic deformation, the material must be caused to flow; therefore, higher rolling speeds are better than lower speeds.

Axial Thread Rolling:
Recommended rolling speeds are 90-270 SFM. The length of the thread determines cycle time.

Radial Thread Rolling:
Recommended rolling speeds are 45-90 SFM. Since radial rolling is complete in one revolution of the roll, rolling time is extremely short (less than 1 second).

Tangential Thread Rolling:
Recommended rolling speeds are 60-240 SFM. The controlled feed rate required in this operation must enable the rolling operation to be completed within 15-30 revolutions of the component. Higher material strengths require lower rolling speeds.

Thread rolling requires no more power than what is normally provided on a standard machine tool.

Axial method: Threads are progressively formed along the axis of the workpiece. Axial heads require only 60% of the torque necessary to cut threads.

Radial method: A complete thread is formed in a single revolution of the rolls. Although this method requires more torque than axial, it does not exceed the machine's capabilities.

Tangential method: A thread is formed in 15–30 revolutions of the component. In this case, the drive power of the spindle is not a critical factor. The power to roll the profile comes from the drive of the cross slide (or turret).

Conventional cutting fluids are normally suitable for rolling applications. For instance, emulsions having a 1:10 to 1:20 dilution are commonly used, sometimes with a high-pressure additive. High-pressure additives will reduce friction between rolls and components, thereby increasing the life of the thread rolls.