Smith-Blair Pipe Repair Caps

Smith-Blair pipe end caps and line caps provide a fast, pressure-rated mechanical closure for plain-end pipe without welding, threading, or flanging. Used to terminate dead-end mains, isolate abandoned pipe segments, cap temporary blowoffs, and close off the ends of installed but un-connected branch lines, these products are an essential part of any water distribution contractor's or utility crew's inventory.

Smith-Blair end caps seal against the pipe OD using a compression gasket and bolt-tightened follower — the same proven sealing mechanism used across the Smith-Blair coupling system. Both steel and cast configurations are available to suit different pipe materials, pressure classes, and installation conditions. Contact us with your pipe OD and we'll confirm the right part number.

Steel Pipe End Cap — Style 481

Style 481 is a fabricated steel end cap engineered for plain-end steel pipe. It uses the same follower-and-gasket sealing system as the Smith-Blair coupling line, with alloy bolt hardware standard and stainless options available. The steel construction provides a rigid, high-pressure-rated closure suitable for raw water transmission mains, industrial pipelines, and temporary hydrostatic testing applications.

• Suitable for steel pipe across a wide range of OD sizes — specify actual pipe OD when ordering
• Alloy bolt hardware standard; 304 stainless hardware available for corrosive soil or water conditions
• Used for dead-end terminations, hydrostatic testing, and temporary closures on live water mains
• Compatible with the Smith-Blair gasket system — BUNA-N standard; EPDM available on request

Cast Line Cap — Style 482

Style 482 is the cast iron version of the Smith-Blair end cap, designed for use with cast iron and ductile iron pipe. The cast construction accommodates the wider OD tolerances inherent in iron pipe and provides the long-service-life characteristics required for permanent dead-end closures on buried water mains. Style 482 uses the OMNI cast coupling body system for a modular, interchangeable assembly with other Smith-Blair cast products.

• Cast iron body compatible with Smith-Blair OMNI coupling components
• Available in standard and long-sleeve sleeve lengths for deeper OD range coverage
• Used on cast iron distribution mains being decommissioned, capped at service abandonments, and temporary isolation points during rehab work
• Sizes available from 4" through large diameter; contact for availability on sizes above 12"

Application Notes

For end caps installed on pressurized systems, thrust restraint must be provided to prevent the cap from blowing off under system pressure. Options include poured concrete thrust blocks bearing against undisturbed soil, mechanical restraint harnesses, or restrained coupling adapters. Consult your project engineer for thrust requirements at system operating and test pressures.

For temporary hydrostatic test applications, ensure the cap is rated for the test pressure specified — Smith-Blair end caps are rated based on pipe size and OD; verify the pressure rating before applying test pressure above the system working pressure.

Ready to Order?

Provide your pipe material, actual outside diameter, and working pressure and we'll confirm the catalog number, pressure rating, and lead time.
Call: 281.664.8000  |  Email: sales@watermainsupply.com