What Are The Production Processes of Lead Screw?
Publish Time: 2025-07-14 Origin: Site
Most of the processes of lead screw are cold rolling and thread rolling. If there is a large step, CNC turning process should be used.
Among them, cold rolling (Cold Rolling) and thread rolling (Thread Rolling) are two common plastic forming processes. They have similarities, but there are differences in technical definition, application scope and process details. The following are the core differences between the two:
1. Definition and nature of process
Technology | Definition | Core features |
（Cold Rolling） | The metal forming process in a broad sense is to apply pressure to the metal billet through the rolling mill at room temperature, so that it can undergo plastic deformation, which is suitable for plates, bars, tubes ect. | Wide range of coverage, not limited to thread processing. -Often used for material pretreatment |
（Thread Rolling） | It refers to the cold forming process of extruding threads on the surface of cylindrical blank by rotating wire wheel or flat die, which belongs to a subdivision of cold rolling. | Specialized for thread forming-only local plastic deformation of the threaded part. |
Key differences:
Cold rolling is a macroscopic forming process (such as the reduction of the diameter of a whole screw), while rolling is a microscopic forming process (only the threaded part is processed).
All thread rolling is cold rolling, but not all cold rolling involves rolling (such as sheet cold rolling and thread is not involved).
2. Comparison of process parameters
Parameter | Cold rolling (general) | Rolling (thread specific) |
Temperature | Room temperature (cold) | Room temperature (cold) |
Pressure | High (overall deformation) | Medium-high (local deformation) |
Speed | lower（10~50 RPM） | higher（100~500 RPM） |
Lubrication | Emulsion or oil based | High viscosity thread special oil |
Precision | IT8~IT10(Diameter control) | IT6~IT8(Tap accuracy) |
Cold rolling is mainly used in the material pretreatment stage such as diameter calibration of screw billet, thickness adjustment of plate and pipe, etc. It does not directly process the thread, while rolling is mainly used in the final formation stage of the thread, such as lead screw thread forming, bolt and screw thread processing, etc.
Case study:
Cold rolling: When producing the screw rod, the diameter of the hot rolled round steel is reduced from Φ12mm to Φ10mm (improving the dimensional accuracy) through cold rolling.
Roll pressing: The lead thread of Tr10×2 is rolled out on the cold rolled billet of Φ10mm.
Sum up
Cold rolling is a general process for metal forming, used to calibrate the dimensions of screw blanks. Roll forming, a specialized application of cold rolling, focuses on thread forming. Together, they complete the manufacturing of screws. When selecting a process, consider factors such as batch size, precision, and material. Roll forming is the preferred method for mass-producing lead screws.