Thread Rolling Inc. is a specialty process supplier of value-added roll threading, roll knurling, and centerless grinding services. Rolled threads have superior characteristics; therefore many threads are required to be formed. TRI is a dedicated business unit and sister company of Horst Engineering.
Outsourced thread rolling processes are often more efficient than producing threads by cutting or grinding, especially on parts made of difficult metals. Customers who prefer to supply their own machined components rely on TRI to help engineer their parts to accommodate rolled threads and knurls. Horst Engineering focuses on producing complete products, including threaded components, but Thread Rolling Inc. helps customers when they choose to supply their own parts. We are ISO9001:2008 and AS9100 registered and proud of our three-generation legacy of quality and performance.
Thread rolling is the preferred method for producing strong, smooth, precise, and uniform external thread forms. Thread rolling is different from other types of threading processes like cutting, grinding, and chasing.
Thread rolling is a cold forging process that can be performed on any ductile metal. The forming process can be used to produce other special forms, such as knurls. For the best quality threads, the process is performed on precision centerless ground blanks. The blank diameter of a rolled thread is at the pitch diameter, a theoretical point between the major diameter and minor diameter.
Thread Rolling Inc. produces rolled threads on a wide variety of parts. Often, rolled threads are required by design because of their superior tensile, shear, and fatigue strength. Other processes remove material to produce the thread form, but thread rolling displaces the material with hardened steel dies. These dies typically have a hardness between a range of Rc58-Rc63 and there is a specific set of dies for each thread size and each thread form. The dies have the reverse for of the finished thread.
The result of moving the material grains (molecules) into the shape of the thread rather than weakening it by removing material, is that the grains become denser at the critical parts of the thread, especially in the root and on the flank below the pitch diameter. This effect improves the quality of the thread form. Additionally, the burnishing action of the steel dies produces an excellent (better than Ra32) micro-finish. The superior finish improves assembly between external and internal threads and reduces wear between mating components, thereby extending their life. A smooth finish is another advantage that roll threaded components have over other threaded components.