Threading is handling the rod or hole in the details with the threading tool for external or internal screw thread, consisting of alternating helical and kanazok projections-turns. Cutting is carried out on pipes, bolts and nuts that are used for releasable connection of pipelines and various pieces of equipment for threading pipe threading machine use. Main the elements of thread: a profile step, the angle of the profile, depth, outer, inner and middle diameter. Cross-sectional shape is called a loop of thread. The profile of the thread are triangular, rectangular, trapezoidal, etc.

When you build sanitation systems and components are used only triangular groove. In the direction of thread turns are divided into right and left. By appointment threads are divided into fixing and special. By fastening thread are triangular, for the special – rectangular and triangular other thread is mounting, because it is cut on fasteners: bolts, nuts, screws. Thread pitch is the distance between peaks or bases of two adjacent coils. Thread profile angle is the angle formed by the intersection of the side faces (sides) spiral threads. Depth of thread 3 is called the distance from the top to the bottom thread.

Outside diameter distance between the tops of two opposite sides of the thread. The inner diameter of the distance between the bases of two opposite sides of the thread. The average diameter of the distance between the top and bottom thread cutting opposite side. The relationship between pitch thread, thread depth and number of turns per unit length of the thread is: the greater the pitch, the greater the depth of the groove and lower the number of threads (turns) per unit length thread, and vice versa.