Short radius and welded elbows
The sphere of usage: For mounting of technological pipelines, thermal power plants and oil pipelines.
Elbows are pipe fittings, which are designed to smoothly change the direction of the pipeline and the gas or liquid. Attaching of the items to the pipes is managed by jam-welding, the pipe should be the same diameter and placed at an angle to each other of the equal elbow angle.
Elbows OST 36-21-77
This standard is used for section welded elbows R=1.5 Du with an angles of 30, 45, 60, 90 degrees of carbon steel at Ru 2.5 MPa (25 kg/sq.cm); t=300 C; Du=500-1400 mm.
OST 34-10752-97
This standard is for welded sector of knee pipes at angles of 15, 30,45, 60, 90 degrees, and made of carbon and low-alloy steel for thermal plants stations pipelines. At P <MPa (22 kg/sq.cm), t=425 C.
Elbows acc.to OST 34-10752-97 are made according to OSTs, TU and GOSTs of welded sheets or sectors of pipes. Elbows differ with various angles, which choose depends on specification and pipeline direction scheme.
Short radius elbow 90 degrees TC 583-000
Forged-welded short radius models are produced in large quantities for industrial and major modifications of the average diameters from Du 219 units to Du 1420.
Short radius elbows have a small radius of the bend so the installation of pipelines becomes much easier, which is especially appreciated by pipe layers.
GOST 17375-01
Such pipes can be of diameter from Du 25 to Du 426. This variation is due to the difference of the technical conditions. If you want to challenge this geometry and with the diameter of the pipe, then the above welded-forged type or welded sectional types can be used. As to GOST 30753-01, the diameter of 530, 630, 720 and 820 mm are available. Elbows can be made of black steel for nuclear industry of stainless alloys.
Section welded elbows (OSS) made of carbon steel is usually used when installing seamless and welded pipes, laying a pipeline that involves changing the direction of flow of the liquid environment. Used in cold and hot water supply, oil and gas pipelines, pipelines of TPP.
Section welded elbows are produced with a typical radius of bending from 1Du and 1.5 Du. Issue is at an angle of 15, 30, 60 and 90 degrees. The working pressure is up to 25 BAR and working temperature should not exceed 200 degrees Celsius. The development comes with the use of a large number of model schemes, but there's always a certain innovation.
On the basis of OST 34.10.752-97 model sizes from 108 to 1620 are available, and are of the most popular. From 500 up to 1420-OST 36-21-77, and if taking rates from 14 up to 426-OST 36-42-81. The latter increased resistance, so that it can withstand the pressure any more units and 5 at 100- of temperature. They are widely used in the petrochemical, food, chemical, metallurgical and light industries.
For producing materials for the manufacture of low-alloyed and carbon steel are used. As well as corrosion-resistant and heat-resistant steel-clad, 15x15M, 12x18H10T, 15H15M, and others.
As practice shows, the most popular and in-demand sector welded steel pipe bends with angles of rotation 90 and 45 degrees. Bends with angles of rotation 15, 30, 45, 60 and 90 degrees are used in piping, working pressure not exceeding 22 kg/cm2, and the working height of 350 with. In addition, it is possible to order the manufacture sector weld removal with an odd angle.
Designation
- An example of a symbol of an elbow at an angle of 90° Du = 530 mm, S = 10 mm of steel VSt3sp: Elbow 90°: 530'10 VSt3sp OST 36-21-77.
- An example of a symbol of the intermediate sector with an angle of 30°, ø 426 mm and wall thickness from 10 mm to nominal pressure Ru 2.5 MPa Sector interim 30°-426'10-2.5 2-43 OST 34 10.752-97
- An example of a symbol of the intermediate sector used as pipe with diagonal slice type B, with an angle of 30°, ø 426 mm, a wall thickness of 10 mm and a length of 1000 mm at nominal pressure Ru 2.5 Mpa: Sector interim 30°-426'10-2.5-1000 2-43 OST 10.752-97 34
Elbows at dispatch
Elbows at dispatch
