Screwed Brass Barrel Union

A barrel union joins two pipes with a joint you can break without unscrewing the whole run. The centre nut releases, the two halves separate, and equipment comes out for service. On any line where something has to be removable, this is the fitting that saves the installation.

Key features

• Joins two female threaded pipes with a separable centre nut
• Lets equipment be removed without dismantling the run
• Machined seat for a positive seal on reassembly
• Manufactured to AS 1722 and AS 3688
• Pressure rated to 3500 kPa (500 psi)
• Temperature range 0°C to +120°C
• BSP threads for local and international compatibility
• Cast or extruded brass for corrosion resistance

Applications

• Either side of a pump, filter or meter
• Fuel and oil lines needing service access
• Natural gas installations
• Water and lubrication systems
• Any line where a component comes out periodically

Compatibility and fitting

• Fit a union each side of anything you expect to remove
• Tighten the centre nut onto its seat; the seal is metal to metal there, not on thread tape
• Do not use thread sealant on the union seat itself
• Seal tapered threads with tape or a sealant rated for the fluid you are carrying
• Brass into brass strips easily: tighten to seal, not to a hard stop
• Do not mix thread standards: a fitting cut to a different standard will start, feel tight and then weep

Where should unions go?

Either side of the removable item, close enough that it lifts straight out. A single union means you are still twisting the component out of one thread.

Mine weeps at the centre nut

The seat is the seal. Separate it, check the faces for grit or a burr, clean them and remake. Tape on the seat makes it worse, not better.

The full range is in brass fittings.

Dispatched from our Brisbane warehouse. Australia-wide delivery, or collect from the warehouse once your order is confirmed ready.