Pioneer, Cornell & Thompson Mechanical Seal — 2-1/2″ T-2 (Tungsten or SiC/SiC)

Pioneer, Cornell & Thompson Mechanical Seal — 2.500″ T-2 (Tungsten or SiC/SiC)

This 2.500″ T-2 mechanical seal is a direct-fit replacement for Pioneer, Cornell, and Thompson pumps built around a 2.500″ shaft and T-2 arrangement (3.375 seat). Built to OEM-equivalent standards or higher, it’s available in two material builds — choose the one that fits your service.

Cross Reference:

• Thompson: PS-3888 — Q55-2520-1T2

• Pioneer: PS-2740 — 30400194, 730400172 (316SS)

• Cornell: PS-22094 — A16421D-40 (316SS)

Choose Your Material

• Tungsten Carbide / Viton — the OEM-equivalent material these pumps are specified with from the factory. Our premium option.

• Silicon Carbide / Silicon Carbide / Viton — a lower-cost alternative build for many standard applications.

At a Glance

• Shaft size: 2.500″ (2-1/2″)

• Type: T-2 (3.375 seat)

• Material options: Tungsten Carbide/Viton (OEM-equivalent, premium) or SiC/SiC/Viton (lower-cost alternative)

• Fits brands: Pioneer, Cornell, Thompson

• Form: Seal assembly only (O-rings/gaskets sold separately)

Material Options Explained 
As specified from the factory, these pumps typically use a Tungsten Carbide seal — that’s our OEM-equivalent, premium option, matching the original spec. We also offer a Silicon Carbide/Silicon Carbide/Viton build at a lower price as a cost-effective alternative for many applications. Both are direct-fit; the Tungsten Carbide matches the OEM material, while the SiC/SiC option is the more economical choice.

Applications

Built for 2.500″ T-2 Pioneer, Cornell, and Thompson pumps. Matching from a worn seal or a parts list? Confirm your pump model and shaft size first, or send a photo of the old seal and your pump nameplate to info@sealhouseusa.com, or call/text 561-414-1046. No purchase required — our seal specialists will match it.

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