Carbon Steel Elbow

Welded Elbow Introduction

Welded elbow alias: Pressed elbow, Seamless elbow, Steel elbow, Forged elbow, Weld neck elbow, etc., the names vary by region, all belonging to the elbow series.

Welded elbow is a metal pipeline fitting used to alter the direction of pipeline on pipes.

Purpose: Connect two pipes, allowing them to change direction at 45-degree, 180-degree, 90-degree angles, or other angles.

Manufacturing Standards: National Standard, American Standard, Japanese Standard, German Standard, Russian Standard

Variety Classification

Welded elbows are categorized by their curvature radius: they can be divided into long-radius elbows and short-radius elbows. A long-radius elbow refers to one where the curvature radius is 1.5 times the pipe's outer diameter, i.e., R=1.5D. A short-radius elbow refers to one where the curvature radius is equal to the pipe's outer diameter, i.e., R=1.0D; (D denotes the elbow diameter, R the curvature radius; D can also be expressed as a multiple.)

Welded elbows are categorized by angle: commonly available are 45-degree, 90-degree, and 180-degree elbows. Additionally, other non-standard angle elbows, such as 60-degree, are included based on engineering requirements.

Welded elbows are categorized by material, including carbon steel elbows, stainless steel elbows, alloy steel elbows, and more.

Welded elbows are divided by pressure ratings: there are approximately seventeen types, and those that are the same as the American pipe standards include: Sch5s, Sch10s, Sch10, Sch20, Sch30, Sch40s, STD, Sch40, Sch60, Sch80s, XS; Sch80, Sch100, Sch120, Sch140, Sch160, XXS, with STD and XS being the most commonly used.

Production Process

Welded elbows can be roughly categorized into: hot-formed, stamping-formed, and mid-plate welded-formed.

The recommended elbow forming process boasts aesthetic appearance, even wall thickness, and continuous operation, making it suitable for mass production. Consequently, it has become the primary forming method for carbon steel and alloy steel elbows, and is also used in the forming of certain specifications of stainless steel elbows.

The bending forming elbow was an early technique used for mass production of seamless elbows, but has been replaced by hot forming or other methods in the production of commonly sized elbows. However, it is still used in certain specifications where the production volume is low, or the wall thickness is excessively thick or thin.

A half-section of the elbow profile is formed using a medium plate and a press brake, and then the two sections are welded together; this process is generally used for the production of large-diameter socket weld elbows with DN700 and above.

Application Fields

Welded elbows are widely used in fundamental projects such as chemicals, construction, water supply, drainage, oil, light and heavy industries, refrigeration, sanitation, plumbing, fire protection, power, aerospace, shipbuilding, and more, due to their excellent comprehensive properties.

Procurement Recommendations

Recommend purchasing from a legitimate elbow manufacturer with a certain production scale.

2: manufacturers of elbows must provide material test reports and related documents for elbows.

3: Elbows must have corresponding specification and model stamping and marking.