Product Overview

PP large-diameter elbows are critical connecting components in large-scale piping systems. They are the most commonly used "turning parts" in corrosive environment ventilation or waste discharge systems. Sizes from φ110 mm to φ800 mm are readily available, and even larger sizes can be fabricated on-site by welding two half-shells together.

Connection Methods

Socket Fusion Bonding:

φ110～250 mm, using PVC/PP special adhesive, initial curing in 1 min, pressure resistance ≤0.3 MPa;

Butt Fusion Welding:

φ315～800 mm, weld strength ≥ 80% of the base material, pressure resistance 0.6 MPa, suitable for chimneys and exhaust pipes;

Flange Connection:

PP flanges are used at the interface with equipment/valves, EPDM gaskets are selected, and SS304 bolts with PP sleeves are used to prevent "crevice corrosion".

Main Types

Classified by Angle:

90° Elbow: Most common, used for right-angle turns.
45° Elbow: Used for gradual turns.
180° Elbow (also known as return bend or U-bend): Used for complete reversal of direction.
Other Non-standard Angles: Such as 30°, 60°, etc., less common.

Classified by Bending Radius:

Long Radius Elbow: Curvature radius R = 1.5D or greater (D is the pipe diameter). Low fluid resistance, less erosion and wear, most commonly used.
Short Radius Elbow: Curvature radius R = 1.0D. Occupies less space, but has higher local resistance and more severe wear.

Classified by Connection Method:

Butt Weld Elbow: Flat ends, used for butt fusion welding. This is the most common connection method for large-diameter PP pipes, offering high strength and low cost.
Flange Connection Elbow: Both ends have PP flanges, connected to the flanges on the pipe using bolts. Easy to disassemble and maintain, often used in places requiring frequent inspection or connection to equipment and valves.
Socket Elbow: Used for smaller diameters, not common in large-diameter applications.