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4″ NBR Hammer Union Seals for Low-Pressure Fig 200/206 Service

Our Hammer Union Seals are engineered to provide leak-free performance in Weco® style union connections used in high-pressure flowlines. Manufactured from high-modulus elastomers and reinforced with anti-extrusion backup rings (Brass or Stainless Steel), these seals withstand the extreme pulsating pressures and abrasive fluids found in hydraulic fracturing and cementing operations.

Technical Specifications

  • Working Pressure Ratings: 1,000 PSI to 22,500 PSI (depending on union rating)
  • Durometer: 80-95 Shore A

Applications

  • Hydraulic Fracking: High-pressure sand and proppant injection lines.
  • Flowback Operations: Managing post-frac fluids and gases.
  • Choke & Kill Manifolds: Safety-critical well control connections.
  • Mud Lines: Circulating drilling mud systems.
  • Acidizing & Cementing: Handling abrasive cement slurries and acid fluids.

1. Executive Summary

Not every connection on a rig is 15,000 PSI. The Figure 200 and Figure 206 unions are the industry standard for Low Pressure (2,000 PSI) suction lines, water transfer, and tank battery connections.

Our 4″ NBR Hammer Union Seals are precision-molded to provide a high-flow, reliable seal for these large-bore connections. Engineered from a fuel-resistant NBR compound, these seals are perfect for handling diesel-based drilling fluids (OBM) and tank bottoms without swelling or degrading.

2. Technical Focus: Suction & Vacuum Service

While most seals focus on keeping pressure in, Fig 200/206 seals often need to keep air out.

  • Vacuum Resistance: On the suction side of a mud pump, a poor seal can allow air to enter the line (cavitation), damaging the pump. Our 4″ seals feature a robust cross-section that maintains contact even under partial vacuum conditions, ensuring pump efficiency.

3. Detailed Parameters

Parameter Specification
Nominal Size 4 Inch
Union Compatibility Figure 200 (Blue/Gray) & Figure 206 (O-Ring Seal)
Pressure Rating 2,000 PSI (138 Bar)
Seal Type D-Ring / Rectangular Profile (Depending on housing)
Material Fuel-Resistant Nitrile (NBR)
Durometer 85 Shore A
Oil Resistance ASTM D471: <10% Volume Swell in Diesel
Applications Suction Hoses, Frac Tanks, Water Transfer

4. Comparison: Why not use a 1502 seal?

  • Geometry: A 4″ 1502 seal is physically different and will NOT fit a 200/206 union.

  • Cost: Fig 200/206 seals are a cost-effective solution for low-pressure lines, avoiding the expense of high-pressure metal-backed seals.