RS PRO HSS PG7-20 Straight Flute Threading Tap, 70 mm Length Model No 427957

RS PRO HSS PG7-20 Straight Flute Threading Tap, 70 mm Length Model No 427957 is a cutting tool used to create internal threads in pre-drilled holes or nuts. It is an essential tool in metalworking, woodworking, and various manufacturing processes where threaded connections are required.

The tap typically consists of a cylindrical shank with helical flutes running along its length. These flutes have cutting edges that gradually taper or decrease in diameter towards the tip of the tap. There are three main types of taps: taper tap, plug tap, and second tap (also known as a bottoming tap).

The taper tap, also called the starting tap, has a more pronounced taper at the end of the flutes, allowing it to ease into the hole gradually. It is used to create the initial threads in a hole, and its tapered design helps to prevent the tap from binding or breaking.

The plug tap, on the other hand, has a shorter taper and is used for threading to a specified depth. It is suitable for through-holes and stops when it reaches the desired depth.

The second tap, as mentioned earlier, is also called the bottoming tap. It has a consistent diameter along its length, with a short chamfer at the starting end. This design allows it to cut threads close to the bottom of a hole, making it ideal for threading holes that have already been partially threaded by the taper tap.

When using a threading tap, the material must be securely held in place, and the tap is rotated clockwise into the hole. The cutting edges of the flutes remove material, forming the internal threads that match the external threads of a corresponding screw, bolt, or nut.

Threading taps come in various sizes and thread pitches to accommodate a wide range of applications. They are made from high-speed steel (HSS) or carbide to withstand the cutting forces and maintain their sharpness over prolonged use.

Proper lubrication is essential during the tapping process to reduce friction and heat generation, improving the tool's lifespan and ensuring accurate thread formation.

In summary, threading taps are indispensable tools for creating internal threads in holes, enabling secure and reliable connections between various components in industries ranging from manufacturing and construction to automotive and electronics.