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Drilling Grade HNBR Weco® Compatible Seals for Sour Crude Oil

Service companies running mixed fleets for Cementing and Acidizing face a dilemma: Standard NBR cannot handle the heat of curing cement, and Viton® (FKM) cannot handle the high pH of cement slurries or the abrasion of proppants.

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.

Drilling Grade HNBR Weco® Compatible Seals for Sour Crude Oil

1. Executive Summary: Optimized for OBM and Sour Crude

Drilling operations present a unique set of challenges: Oil-Based Muds (OBM), chemically aggressive sour crude from the formation, and the abrasive wear of drill cuttings. Standard HNBR can sometimes swell excessively in high-aromatic diesel muds.

Our Drilling Grade HNBR Seals are precision-formulated with a High-Acrylonitrile (ACN) content. This specific chemistry minimizes volume swell in hydrocarbons while maintaining the toughness required to survive the solids control circulation loop. Compatible with all Weco® style unions, these seals are the premium choice for the mud system.

2. Material Science: The ACN Balance

Controlling Volume Swell

“Swell” happens when the elastomer absorbs the fluid it is sealing.

  • Low ACN HNBR: Better low-temp flexibility, but swells 10-20% in Diesel/OBM.

  • Our Drilling Grade (High ACN): We utilize an ACN content >43%. This tightens the molecular structure against hydrocarbon ingress, keeping Volume Swell < 5%.

  • Why it matters: A swollen seal will extrude and shear off when the union is disconnected, requiring replacement every time. Our Low-Swell HNBR can often be reused, saving money.

3. Comprehensive Data Sheet

Technical Parameter Specification
Grade Drilling Grade HNBR
Primary Fluid Oil-Based Mud (OBM), Sour Crude
ACN Content High (>43%)
Hardness 95 Shore A (Extra Hard)
Pressure Rating Up to 15,000 PSI
Temperature -20°F to +300°F
Sizes Available 2″, 3″, 4″, 5″, 6″
Compatibility Fits Weco®, Kemper®, FMC® Unions

4. Field Applications in Drilling

  • Standpipe Manifolds: High-pressure mud delivery.

  • Shale Shakers: Seals exposed to high vibration and solids.

  • Mud Gas Separators: Equipment handling “gas kicks” containing H2S.

  • Choke Manifolds: Flow control during well kicks.

5. Compatibility Statement

These seals are engineered as Aftermarket Replacements that meet or exceed OEM specifications. They provide a cost-effective solution for rig managers looking to reduce daily operating costs (OpEx) without sacrificing safety or performance in sour drilling environments.