Elbow

Welded Elbow Introduction

Welded elbow alias: Pressed elbow, Seamless elbow, Steel elbow, Forged elbow, Weld neck elbow, etc., different regions have different names, all belonging to a type of elbow series.

Welding elbow is a metal pipeline fitting used to change the direction of the pipeline on a pipe.

Purpose: Connect two pipes, allowing the pipes 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 elbow curvature radii: They can be divided into long-radius elbows and short-radius elbows. Long-radius elbows refer to those with a curvature radius equal to 1.5 times the pipe outer diameter, i.e., R = 1.5D. Short-radius elbows refer to those with a curvature radius equal to the pipe outer diameter, i.e., R = 1.0D; (D is the elbow diameter, R is the curvature radius; D can also be expressed in multiples;)

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

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

Welded elbows are categorized by pressure ratings: approximately seventeen types, which are the same as the American pipe standards and 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 broadly categorized into: hot-pressed, stamping, and midplate welding formed.

The hot-push elbow forming process is highly recommended for its aesthetically pleasing appearance, uniform 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.

Bent pipes formed by stamping are an early forming process used in the mass production of seamless bent pipes, which have been replaced by hot pushing or other forming methods for commonly used specifications. However, in certain specifications, bent pipes with fewer production quantities, excessively thick or thin walls, still use this stamping forming process.

A half-section of the elbow profile is formed using a medium plate and a press, 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

Due to the excellent comprehensive properties of welded elbows, they are widely used in basic engineering fields such as chemicals, construction, water supply, drainage, oil, heavy and light industries, refrigeration, sanitation, plumbing, fire protection, electricity, aerospace, shipbuilding, and more.

Procurement Recommendations

1: Recommend purchasing from a reputable elbow manufacturer with a certain production scale.

2: Manufacturers of elbows need to provide material inspection reports and other relevant documents.

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