Dresser Gasket — Style 90 | Replacement Gasket for Style 90 Gas Service Compression Fittings

Natural Gas Service Lines | Cast Iron or Forged Steel Body | Grade 27 BUNA-S Armored Standard | Pull-Out Resistant | Up to 2 in Nom.

Overview

The Dresser Style 90 Gasket is the factory-specified replacement sealing element for Dresser Style 90 Compression Fittings — one of the most widely installed compression fitting systems in natural gas distribution service line work in North America. The Style 90 fitting has become the preferred coupling for gas service lines due to its unique combination of a compression-sealed joint, a steel self-centering protective gasket retainer cup, and a fitting body designed to resist pipe pull-out more effectively than standard compression fittings. Tens of millions of Style 90 fittings have been installed on gas service lines where they continue to provide decades of leak-free service.

The Style 90 fitting body is constructed of cast iron or forged steel (not malleable iron), which provides greater structural strength than the Style 65 fitting body, making the Style 90 the preferred choice when the service line is subject to soil movement, settling, or other longitudinal forces that could put the joint under stress. The Grade 27 BUNA-S Armored gasket is standard, providing the brass-coil electrical continuity path required for cathodic protection continuity through the gas service line.

What Is the Dresser Style 90 Compression Fitting?

The Dresser Style 90 is a heavy-duty compression fitting system designed specifically for natural gas service lines and high-stress pipeline applications where the Style 65 system's malleable iron body does not provide sufficient structural strength. The Style 90 consists of a cast iron or forged steel body, two specially compounded compression gaskets, two steel self-centering protective gasket retainer cups, and two heavy end nuts. The retainer cups protect the gasket during tightening and improve axial load resistance — making the Style 90 substantially more resistant to pipe pull-out than standard compression fittings. Style 90 is also available in a universal version that accommodates a wider range of pipe ODs within a single coupling.

Key Features

• Forged Steel or Cast Iron Body: Substantially stronger than the malleable iron used in Style 65 bodies — required for gas service line applications where soil settlement, frost heave, or traffic loading creates longitudinal stress on the service line joint.
• Steel Self-Centering Retainer Cups: Protect the gasket sealing lip during installation and tighten the gasket in a controlled, concentric pattern — improving sealing uniformity and pull-out resistance versus plain-gasket compression fittings.
• Grade 27 Armored BUNA-S Standard: The brass coil integral to the armored gasket maintains electrical continuity through the fitting joint, enabling cathodic protection current to pass through the gas service line connection without interruption.
• Heavy End Nuts: Heavier nut construction than Style 65 provides greater tightening torque capacity and longer-term stability under vibration and thermal cycling.
• Universal Style 90 Available: A universal version accommodates a wider range of OD variation within one fitting, reducing the number of SKUs required in the field for systems with mixed pipe vintages or OD tolerances.
• Ships Fully Assembled: Ready-to-install as received. No disassembly, no special tools, no threading or flame required.
• Grade 42 Armored Available on Request: For condensate-carrying gas lines or multi-phase service where BUNA-N chemical resistance is required over standard BUNA-S.

Gasket Specifications

Style 90 vs. Style 65 — Choosing the Right Fitting

Questions? Contact us at sales@watermainsupply.com or call 281.664.8000.