Thread rolling: Stable processes at small businesses in focus
Chipless thread fabrication using a thread rolling head has a full range of advantages: the finished surfaces are smooth and have increased strength, and the material fibers remain unbroken. An English example illustrates how the highly reliable process offered by this method is important, in particular, for small businesses. The component supplier LMS Precision Engineering is using thread rolling head from LMT Fette in the fabrication of jointing elements from EN1A steel, and gains a competitive advantage through this process.
Thread rolling is faster, more precise and more economical than any chip-forming fabrication method – valuable advantages for almost every production situation. At the same time, the process is unusually stable and reliable. This is precisely the property emphasized by Roger Street from LMS Precision Engineering: "Our small team often has to handle very different jobs at the same time on the turning centers we have. Our employees do this working a single shift with great flexibility – for example, they all have their own key to the production area, and many of them are regularly there outside normal hours monitoring the process." Street adds that "In this context it is therefore very helpful for a machining process to run both stably and with high effectiveness".
Threads formed in less than a second of machining
Working as a subcontractor on jobs for larger component companies, LMS produces highly varied components used, for instance, in aircraft construction or in the automobile industry. These cutting experts, based about 50 kilometers south of Birmingham in Worcestershire, have just received an order for the production of, to begin with, 4000 jointing elements with external threads made of EN1A steel. "For this job we made contact with LMT UK, because, considering the high parts count, we wanted to be sure that we would be using the best tool process for the job. What strategy, running on which machine, would bring the best results? That was the key question", explains Street. Together with the experts at LMT, the production planners at LMS then decided in favor of using an radial thread rolling head of LMT Fette on the Citizen Sliding Head L-Series machining centre.
- Thread rolling head from LMT Fette.
Quality pays straight away
The external M3 thread on the jointing element, which is altogether 10 mm long, is fabricated in this way at a speed of 2000 rotations per minute, taking less than one second of machining – until now, LMS needed almost 7 seconds to fabricate similar items using chip-forming methods. After inspecting the first sample parts, the client then decided to have the whole batch of 40,000 components made at LMS. At first it had been planned to distribute production across a number of subcontractors. LMS then needed one month to complete the entire job.
"And there is another way in which our client has confirmed just how good the chipless production method is: one of our customers has even specified, on their technical drawings, that the thread of a component must be rolled." Street concludes that " The customer quite simply wants quality".