Welded Concentric Pipe Reducer

Welded Concentric Pipe Reducer

Hebei Longrun Pipeline Group Company also manufactures welded concentric pipe reducers, offering a practical and flexible solution for piping systems with a wide range of diameters, wall thicknesses, and material specifications. Welded concentric reducers are widely used in industrial applications where dimensional customization, large diameters, or cost efficiency are key considerations.

Structural Characteristics and Design Principles

A welded concentric pipe reducer consists of steel plates or pipes that are formed and welded to create a symmetrical reduction along a common centerline. The concentric design allows smooth flow transition and balanced load distribution, making these reducers suitable for both horizontal and vertical pipeline installations.

Welded reducers are often selected for large-diameter pipelines or special thickness requirements that may be difficult to achieve through seamless forming. They can be produced in a wide range of reduction ratios and customized lengths.

Material Preparation and Welding Procedures

Production begins with carbon steel or alloy steel plates or pipes that meet applicable standards such as ASTM, EN, or GB. Incoming materials are inspected for chemical composition, mechanical properties, and surface quality. Plates are cut using CNC plasma or flame cutting equipment to ensure accurate dimensions.

The formed sections are assembled and welded using controlled welding processes such as submerged arc welding (SAW), gas shielded welding, or manual arc welding, depending on thickness and design requirements. Welding parameters are strictly controlled to ensure penetration depth, bead shape, and metallurgical consistency.

Weld Inspection and Quality Assurance

Weld seams are subjected to comprehensive non-destructive testing, including radiographic testing (RT) or ultrasonic testing (UT), to verify weld integrity. Visual inspection and dimensional checks are conducted to confirm alignment, roundness, and concentricity.

Post-weld heat treatment may be applied to relieve residual stress and improve toughness, especially for thick-wall reducers or low-temperature service materials. This step enhances the long-term stability of the welded joint under pressure and thermal cycling.

Dimensional Accuracy and Finishing

After welding and heat treatment, the reducers undergo machining to achieve precise end diameters and bevel angles. CNC equipment ensures consistency with standard tolerances, facilitating on-site installation and welding.

Surface treatment options include shot blasting to remove scale and welding residue, followed by protective coatings such as primer paint, epoxy coatings, or other corrosion protection systems based on project requirements.

Testing and Certification

Each welded concentric reducer is supplied with full quality documentation, including material test certificates (EN 10204 3.1), welding procedure qualification records, and inspection reports. Hydrostatic testing can be performed upon request to verify pressure resistance.

The quality management system at Hebei Longrun Pipeline Group Company follows ISO-based procedures, ensuring traceability from raw material to finished product.