Leaded Fuels, Spark Plugs and Thread Rolling

Rolling threads on various materials became a necessity in high volume manufacturing in the US following its discovery in Germany after the second world war.

The most dramatic effect was in the production of spark plugs. In the US alone, more than 10 million spark plugs were being produced daily by several manufacturers. Leaded fuels were necessary to lubricate engine valves but subsequently fowled spark plugs limiting their useful life to about 10,000 miles. When lead was outlawed in motor fuels in the 1970’s hardened valve seats became the standard and without lead fowling spark plugs, spark plug life increased more than 10-fold. This reduced product demand 10-fold. Thread rolling migrated from multi spindle screw machines to modern CNC machines for the very same reasons.

Cold forming of threads became equally important in lower volume production from a time and cost consideration. Threads can be formed typically at 1 inch of thread per second of cycle time. A cold formed thread has greater yield strength and surface quality than a cut thread. Many materials that are difficult to cut are easy to roll. Time cycles and part volume create significant value in throughput cost. This value impacts on the final cost of the finished product.

In a job shop atmosphere, it can be the strategic difference between winning the quote or losing the work to a lower bidder. Rolled threads can reduce the effects of corrosion improving life cycles in many applications. The relative ease of applying this technology to today’s metal working machines makes it even more important as a value-added component of the modern machine shop.

We can evaluate your part, your process and your machine when applying the application of thread rolling to your operation. Thread rolling was once conceived as a “black art” but is truly a straight forward application driven technology easily applied in any modern machine shop. Many military and aviation components demand rolled threads for strength and surface quality. Let us help with your application.  The cost implications can be the leverage your company needs to improve profitability.

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