Where Acme & Buttress Thread Forms Are Used and Why

Acme and Buttress threads are extremely useful for the lead screw shaft of various assemblies. Specifically, for assemblies thatmove efficiently either for load bearing or accuracy.  We can see the lead screw shafts in some equipment; however most are hidden from sight.  For example, lifting pallets, marking and labeling machines, medical diagnostics and personal mobility, off road equipment, and machine tools, all require load bearing or accurate movement which can be provided by devices that use a lead screw mechanism.

The thread forms normally required for lead screws are shaped to offer high strength and accuracy. Acme is the most popular trapezoidal thread form worldwide for lead screws. Although square threads are the most efficient, they remain difficult to produce.  Because an Acme 29° angle is easier to produce, both in external and internal threads, it is less expensive. They can be produced with multiple start threads, left hand threads and self-centering threads.

Regal offers standard sizes of Acme taps and manufactures many variations of special purpose taps usually coarse pitch Acme forms. Our most popular style is the “Unipass” Acme, which utilizes both a roughing and finishing section in one tool.

The buttress thread form is designed to handle extreme high axial thrust in one direction. This is typically a 7° angle on the weight bearing surface and a 45°angle on the trailing flank, which provides a form with good shear strength.

Regal manufactures this style to customer specifications in twelve days or less. Contact us today to find out more information. 


Acme Taps

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