Parker 3GF-12 Brass Flared Tube Seal Bonnet 3/4 in 45 Deg

Product Description

The PARKER 3GF-12 is a brass flared tube seal bonnet designed to cap or seal a flared tube end in hydraulic, pneumatic, refrigeration, and fluid-system lines. It accepts a 3/4-inch outside-diameter tube with a standard 45-degree flare angle and mates with a compatible flare fitting to create a leak-free mechanical seal. Constructed entirely of brass, it offers solid corrosion resistance in wet or chemically active environments. Plumbers, HVAC technicians, and pipefitters use this type of fitting to plug inactive ports or protect flared tube ends during system servicing or staged installation work.

This seal bonnet is suited for residential and light commercial applications where 3/4-inch OD flared tubing is in use, including refrigerant lines, fuel-gas distribution, hydraulic circuits, and water-service piping. It is installed wherever a flared tube end must be sealed off temporarily or permanently, making it a standard item in HVAC/R service kits, plumbing rough-in work, and industrial fluid-system assemblies.

Key Features

• 45-degree flare angle matches the industry-standard SAE flare profile for a reliable metal-to-metal seal
• 3/4-inch tube OD sizing fits common refrigerant suction and liquid lines as well as fuel and hydraulic tubing
• Solid brass construction provides corrosion resistance across a wide range of fluid media
• Flare-end connection requires no solder, cement, or thread sealant at the sealing interface
• Compact seal bonnet profile allows use in tight spaces where full fittings would not fit

Compatibility

Designed as an OEM-style replacement fitting for systems using 3/4-inch OD tubing with a 45-degree SAE flare end connection.

Installation Notes

Installation is performed by licensed plumbers, HVAC/R technicians, or pipefitters depending on the application. Depressurize and isolate the line completely before removing or installing any fitting. Hand-tighten the seal bonnet onto the flared tube end first, then torque with a properly sized open-end wrench — do not use pipe wrenches or adjustable pliers that may deform the brass flats. Follow applicable code requirements, including IFGC for gas lines or the applicable ASHRAE or EPA regulations for refrigerant-side work.