Eaton 3129X4 Pipe End Cap 1/4 in Fnptf 1200 Psi

Product Description

The EATON 3129X4 is a straight pipe end cap designed to seal 1/4 inch female FNPTF threaded pipe ends in industrial fluid and pneumatic systems. Rated to 1200 psi maximum working pressure, it handles demanding service conditions across a temperature range of -65 degrees F to 250 degrees F. The FNPTF thread form provides a pressure-tight seal without the need for additional sealant tape in many applications. This fitting is installed by licensed plumbers, pipefitters, and industrial maintenance technicians on both new construction and retrofit work.

This end cap is suited for use in compressed air, hydraulic, and general-purpose fluid piping systems where a threaded port or line end must be closed off cleanly and permanently. Its compact overall length of 9/16 inch and 11/16 inch hex size make it practical in tight spaces where larger fittings cannot be maneuvered easily. Typical install scenarios include capping unused branch ports on manifolds, sealing test points after commissioning, and plugging dormant lines during system modifications.

Key Features

• 1/4 inch FNPTF female thread for direct engagement with male NPT pipe ends
• 1200 psi maximum working pressure rating
• Operating temperature range: -65 degrees F to 250 degrees F
• Compact 9/16 inch overall length for use in space-restricted installations
• 11/16 inch hex size for standard wrench engagement
• UL Listed

Compatibility

Designed as an OEM-style replacement end cap for industrial piping systems requiring a 1/4 inch FNPTF straight pipe closure rated to 1200 psi.

Installation Notes

Installation should be performed by a qualified pipefitter or plumber in accordance with applicable codes, including ASME B31 piping standards where applicable. Depressurize and isolate the line completely before removing any existing fitting or installing this cap. Apply thread sealant compatible with the system fluid if the application requires it, as FNPTF threads are designed for pressure-tight engagement but conditions vary. Use a properly sized wrench on the hex to avoid overtightening and thread damage.