Pipeline fittings

The main function of bends is to change the path of the pipe and the direction of the working flow. This type of pipeline fittings is one of the most common in pipelines. Visually, this part can be represented as a pipe segment bent at a certain angle. Elbows are made of steel 20, steel with increased corrosion and cold resistance 20YuCh, 09G2S or 13HFA, alloy steels 12Kh1M1F or 12Kh18N10T.

Taps are used in chemical pipelines, water pipelines, heating mains, gas pipelines, etc.

According to the manufacturing method, the connecting branches of pipelines are distinguished into:

• bent with an angle up to 90 °. Made by cold bending or high temperature.
• stamped - are made by stamping blanks and their subsequent welding.
• solid-drawn bent - are made by pulling along a horn-shaped core. A feature of solid-drawn bent bends is a small radius of curvature.
• welded sectional - are made by welding pipe cuttings.

The ring blanks plant supplies stamped and solid-drawn bent bends, as well as steeply curved products with a small radius and characterized by the following angles of rotation 45 degrees, 60 degrees, 90 degrees, 180 degrees.

Bends are made according to GOST 17375-2001 from DN 150 to DN 1000 with different wall thicknesses, as well as according to the customer's drawings.

Steel transitions are an important element of pipelines, designed to smoothly change the diameter of the pipeline, to distribute pressure and plan the loads on the system. Concentric transitions are installed mainly in vertical pipelines, eccentric - in horizontal ones.

Steel transitions are divided into:

• concentric - for connecting two pipes along the central axis of symmetry of the pipeline in accordance with GOST 17378-2001 from DN 150 to DN 1000 mm;
• eccentric - for connecting two pipes along the lower generatrix line in accordance with GOST 17378-2001 from DN 150 to DN 500 mm.

Steel transitions are made by stamping or by centrifugal electroslag casting. Depending on the working environment, the transitions are made of steel grades 20, 20YuCh, 09G2S, 12Kh1MF, 13KhFA, 15KhM, 15Kh5M, 12Kh18N10T and 10Kh17N13M2T.

The transitions are subject to increased requirements for reliability and strength, corrosion and cold resistance, the ability to work in an aggressive environment.

Steel tees are pipe fittings that allow you to connect additional branches to the main pipe for branching the flow of the working medium. They are manufactured by cold stamping, welded and stamped-welded methods, followed by heat treatment.

Depending on the ratio of the body and neck diameters, transition and equal tees are distinguished:

• Reducing tees have different diameters of body and neck bores. These tees use smaller diameter pipe branches to the longitudinal axis of the main line. Manufactured in accordance with GOST 17376-2001 from DN 150 to DN 400 mm.
• equal tees, unlike transition tees, have the same diameters of the body and neck holes. Manufactured in accordance with GOST 17376-2001 from DN 150 to DN 1000 mm.

Tees installed on pipelines are exposed to significant dynamic loads and the action of relatively high temperatures and pressures, therefore, they are subject to increased requirements for strength and reliability, corrosion and cold resistance, and the ability to work in an aggressive environment.

Steel tees are made of the following steel grades: 20, 20Yuch, 09G2S, 12H1MF, 13HFA, 15HM, 15H5M, 12H18H10T and 10H17H13M2T.