Dresser Gasket — Style 4 / Style 41 | Replacement Gasket for Collar Leak Clamps

Style 4 Collar Clamp (2 in – 4 in) | Style 41 Collar Clamp (6 in – 12 in) | Grade 27 BUNA-S | Leak Repair Without Service Interruption

Overview

The Dresser Style 4/41 Gasket is the factory-specified replacement sealing element for Dresser Style 4 and Style 41 Collar Leak Clamps — the pipe repair products used to stop leaks at threaded couplings (screwed collars), solvent-weld PVC joints, stab-type PVC connections, and at-grade collar joints without cutting out the fitting or interrupting service. The split-gasket design allows the clamp to be installed directly over the collar or fitting body with no need to remove the pipe section — making this one of the few permanent pipe repairs that can be performed live, on a pressurized line, without shutting down service.

Style 4 Collar Clamps cover nominal pipe sizes 2 in through 4 in. Style 41 Collar Clamps cover 6 in through 12 in. The Style 4/41 gasket is a split, two-piece design — both halves are included per order — molded to match the specific body radius and flare geometry of the Style 4 and Style 41 clamp bodies. The standard compound is Grade 27 BUNA-S.

What Are Dresser Style 4 and Style 41 Collar Clamps?

Dresser Style 4 and Style 41 Collar Clamps are used when a leak develops at a threaded collar, screwed coupling, solvent-weld joint, or stab-type PVC connection. Rather than excavating, cutting the pipe, and replacing the collar entirely, crews slide the split clamp over the leaking fitting and tighten it down — the split gasket conforms to the collar geometry, producing a leak-proof seal that contains the joint from the outside. Repairs are permanent and made under pressure without service interruption in the majority of applications. The Style 4 (2 in–4 in) uses malleable split follower rings with interlocking ends and spring-loaded bolts. Style 41 (6 in–12 in) uses the same operating principle in a heavier construction suitable for larger diameter pipe.

Key Features

• Split Two-Piece Design: Both gasket halves included per unit. Split design allows installation over existing collars without disassembly of the piping system.
• Covers Both Style 4 and Style 41 Clamps: One gasket part number covers both the 2 in–4 in (Style 4) and 6 in–12 in (Style 41) clamp families in their respective sizes.
• Enables Live Line Repair: Used on pressurized lines — repair without service interruption in most applications, eliminating costly shutdowns and dewatering.
• Fits Threaded, Solvent-Weld, and Stab-Type Joints: Compatible with all common collar configurations — screwed coupling collars, solvent weld collars, stab-type PVC joints — in water distribution, gas distribution, and general pipeline service.
• Grade 27 BUNA-S Standard: Wide service range covers water (fresh and salt), gas, air, most acids, alkaline solutions, and refrigerants. Potable water safe.
• Grade 42 BUNA-N Available: For oil, hydrocarbon, and natural gas condensate service where standard BUNA-S is not chemically compatible.
• Permanent Repair: Unlike temporary repair clamps, the Style 4/41 system is rated as a permanent repair method under normal service conditions.

Gasket Specifications

Size Coverage — Style 4 vs. Style 41

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