The Dormer A976 extra-length drill bit is a 130-degree PFX point, parabolic flute round shank, drill bit made of HSS and cobalt. Designed to drill holes up to 15 times the diameter of the drill. The shank diameter is the same as the drill size. Best performance in steel, but also good performance in stainless steel, cast iron, titanium, copper, and unalloyed aluminum magnesium
The A976 PFX series allows for single pass drilling, which eliminates the need for pecking in up to 10 times the drill diameter deep holes, thus offers improved efficiency, and increased productivity. The parabolic design, combined with a parallel thinned web, allows for smooth and efficient chip (also called swarf) evacuation. With proper cutting conditions and rigid machine set-up, holes to H10 tolerance can consistently be achieved.
Coming with a uncoated finish and Smooth-Flow coating, this helps increase chip removal and helps in wear resistance. Spiral flutes act as a passageway for chip extraction from the hole and for coolant to enter the hole. Right-hand twist brings chips up and away from the cutting edge.
Made of HSS with cobalt which is many times harder/stiffer than HSS, will hold an edge longer, and will deflect less than HSS. These are also more resistant to heat than HSS. These qualities allow it to run at higher speeds and feeds. They are made to DIN 1869 series 1 (metric sizing) and ANSI (fractional sizing) industry standards, which help ensure that drill bits around the world conform to the same specifications.
Drilling, or hole making, is the most common metalworking operation in the world. Twist drill bits are the most common type of drill bit used. Twist drill bits are commonly used to drill holes with hand-operated drills, standalone drill presses, or lathes. The flutes of the drill bit act a passageway for chip extraction from the hole and for coolant to enter the hole. These drill bits have a right-hand twist that brings chips up and away from the cutting edge.
Dormer Pramet manufactures cutting tools under the following brands: Precision Twist Drill, Dormer, Union Butterfield and Pramet. The company has locations around the world, and provides tools adhering to ANSI, NAS, and DIN standards.