Large Diameter Pipe Tee

 Large Diameter Pipe Tee – Handling High-Volume Branch Connections

Introduction
Large diameter pipe tees are specialized fittings designed for branching pipelines with nominal diameters above DN 600 (24″), accommodating high-volume flow distribution in major process networks and municipal infrastructures. These sizable tees require tailored manufacturing and handling to maintain structural integrity and flow uniformity. Hebei Longrun Pipeline Group Company offers large diameter pipe tees that fulfill demanding requirements in water transmission, power plants, and oil and gas distribution systems.

Materials and Grades

Carbon Steel (A234 WPB): Standard for water and low-pressure media.

Alloy Steels (A234 WP11/WP22): For steam and high-temperature service.

Stainless Steel (A403 WP304/316): Corrosion resistance for potable water and chemical lines.

Special Alloys: Nickel-based and duplex grades for offshore and highly corrosive processes.

Design Considerations

Equal and Reducing Tees: Equal tees maintain uniform diameters on all branches; reducing tees provide smaller branch lines for metering or bypass.

Reinforcement Pads: Added plate reinforcements around branch intersections to strengthen large-scale junctions.

Saddle-Type Branches: For extremely large mains where full-tee forging is impractical, saddle weld-on branches are used.

Manufacturing Workflow

Forging or Fabrication:

Forged Tees: For diameters up to DN 800 where heavy forging presses are available.

Fabricated Tees: Plate and pipe sections are cut and welded for diameters above DN 800.

Heat Treatment: Normalizing of forged blanks and stress-relief of welded assemblies to control grain structure and residual stresses.

Machining: CNC machining ensures precise branch connections, bevel angles, and flange surfaces.

Nondestructive Testing: Full radiographic examination of weld seams and ultrasonic thickness checks across the branch area.

Surface Treatment: Shot blasting followed by primer or epoxy lining for internal corrosion protection in water or chemical service.

Specifications

Size Range: DN 600 (24″) up to DN 2400 (96″) and beyond on request.

Pressure Classes: ANSI Class 150–600 for large diameters; higher classes upon special design.

Standards: ASME B16.9 for tees up to DN 1200; fabricated under ASME Section VIII for larger sizes.

Applications

Water Transmission Mains: Branching off large supply lines to district distribution networks.

Power Station Steam Lines: Diverting high volumes of steam to multiple turbine or generator units.

Oil & Gas Pump Stations: Splitting crude oil or gas flows to parallel compressors or separators.

Firewater Networks: Large headers branching to hydrant loops in industrial complexes.

Installation Guidelines

Rigging and Lifting: Use certified lifting equipment and spreader bars to prevent deformation during handling.

Alignment and Fit-Up: Dry assembly with guide pins or plates to ensure branch connections are square and stress-free.

Welding Procedures: Multi-pass welding with controlled interpass temperatures; qualified WPS for thick sections.

Pre-Commissioning Tests: Hydrostatic testing at 1.25× working pressure; dye penetrant checks on root passes.

Maintenance Practices
Scheduled inspections using in-line inspection tools (smart pigs) or external ultrasonic scans monitor wall thickness and detect anomalies. Recoating or application of internal liners may be necessary in abrasive or corrosive media.

Conclusion
Large diameter pipe tees from Hebei Longrun Pipeline Group Company enable efficient, high-capacity branching in major pipeline networks. Through specialized forging and fabrication techniques, strict quality controls, and comprehensive testing, these fittings deliver dependable performance for critical infrastructure and industrial applications.