The Dormer MTT-X E009 powdered-metal steel thread forming tap has a round shank with a square end, titanium nitride (TiN) coating, and lubricant grooves, and is used for cold-forming metric right-hand threads in ductile materials such as steel, stainless steel, titanium, nickel, and aluminum. It is available in ANSI standard metric sizes and is suitable for threading through holes (extending through the workpiece) and blind or bottoming holes (with only one opening). Titanium nitride (TiN) is a ceramic coating that combines hardness and low friction to extend the life of the tap, as well as to permit faster cutting speeds than with uncoated taps. The lubricant grooves on this thread forming tap create paths for coolant and lubricant to reach the taper threads of the chamfer, where forming occurs. The tap’s modified bottoming chamfer has additional length to reduce chip load, adds tool life in difficult-to-machine materials, and permits higher tapping speeds.
Right-hand threads are designed to tighten when a head or nut is rotated clockwise (the most common threading direction). Powdered-metal steel offers performance that approaches that of solid carbide tools but with the toughness and shock-resistance of high-speed steel. The round shank with square end helps to minimize rotation in the tool holder. This thread forming tap can be used in machines such as drill presses or lathes.
In the Dormer MTT-X E009 series, taps are designed with varying numbers of lubricant grooves depending upon size. All taps in this series have modified bottoming chamfers. This tap conforms to ANSI standards and can create threads to a depth two-and-a-half times its diameter. It is suitable for the 6HX tolerance class: 6HX exceeds the standard tolerance to increase tool life in tapping high-strength or abrasive materials that do not create oversize problems.
Taps produce internal threads in previously formed holes and can be used in machines (such as drill presses) or with hand tools. Common types of taps include hand taps, spiral point taps, spiral flute taps, thread forming taps, and pipe taps. Hand taps (straight-flute taps) collect chips in the straight flutes of the tool; spiral point taps push chips through holes ahead of the tool; and spiral flute taps pull chips back from the tip of the tool, up and out the hole. Thread forming taps, also known as cold forming taps, press rather than cut to create threads in a drilled hole, and no chips are created. Pipe taps create threads in pipes and pipe fittings. Each thread type designates a thread profile and each type is identified with an abbreviation. In the U.S. and Canada, the Unified Thread Standard is the dominant thread type, including UNC (Unified Coarse), UNF (Unified Fine), and NPT (National Pipe Taper) threads, among others.
Precision Dormer manufactures cutting tools under the following brands: Precision Twist, Dormer, and Union Butterfield. The company has locations around the world, and provides tools adhering to ANSI, NAS, and DIN standards.