Brass Vibra-Lok Straight Connector

A Brass Vibra-Lok Straight Connector is a heavy-duty male-to-tube transition fitting designed to join smooth metal or plastic tubing directly into a female pipe thread port (NPT or BSPT). Rather than cutting a groove into the tube with a metal ferrule, it utilizes a thick elastomeric sleeve (Buna-N or Viton/FKM). As the brass nut is tightened, the sleeve is compressed radially against the tube exterior, forming a resilient, leak-tight 360-degree cushion that isolates the tube from dynamic mechanical vibration.

In conventional compression fittings, dynamic machinery vibration concentrates cyclical bending moments directly at the sharp edge of the metal ferrule, causing rapid work-hardening and fatigue cracking. The Vibra-Lok design suspends the tube within a resilient elastomeric matrix, dampening up to 90% of dynamic mechanical harmonics and permitting the tube to flex safely without metal-to-metal gouging.

Pioneer Industries supplies Vibra-Lok sleeves in two primary compounds: Standard Buna-N (Nitrile) for petroleum fuels, hydraulic oils, compressed air, and water between -35°C and +100°C (-30°F to +212°F); and High-Temperature Fluorocarbon (Viton / FKM) for synthetic lubricants, aggressive fuels, and elevated operating temperatures from -26°C to +204°C (-15°F to +400°F).

Working pressures reach up to 2,000 PSI (138 bar) in 1/8″ to 1/4″ tube OD sizes, 1,500 PSI (103 bar) in 5/16″ and 3/8″ OD, and up to 1,000 PSI (70 bar) in 1/2″ OD sizes, with an ASME B31.3 certified 4:1 hydrostatic burst safety margin. For vacuum applications, its continuous 360-degree radial elastomeric seal holds vacuum down to 29.5 in. Hg.

No. The Vibra-Lok Straight Connector is 100% flareless. Installation requires only square-cutting and deburring the tube end, sliding the nut and elastomeric sleeve onto the tube, inserting the tube into the fitting until it bottoms against the internal stop, and tightening the nut finger-tight plus exactly one full turn (360°) with an open-end wrench.

Because the sealing element is a compliant elastomer rather than rigid metal, the sleeve conforms under compression to minor tube out-of-roundness, longitudinal tooling scratches, and angular misalignments up to 4 degrees. This eliminates leaks caused by slight surface abrasions that typically defeat rigid compression ferrules.

Yes. Because the elastomeric sleeve does not swage, cut, or crimp a permanent groove into the tubing wall, the tubing remains undamaged and 100% reusable. Disassembly simply requires loosening the nut. If the elastomer becomes aged or heat-hardened after years of service, inexpensive replacement sleeves restore the joint to factory-fresh sealing integrity.

The fitting is fully compatible with soft copper, half-hard drawn copper, seamless aluminum, brass, thin-wall hydraulic steel, and even lab-grade glass tubing. When utilizing thermoplastic tubing like Nylon or Polyethylene, brass tube support inserts should be inserted into the tube bore to prevent wall collapse.

Apply high-quality PTFE paste sealant or 2-3 wraps of PTFE tape to the male pipe threads only, leaving the first two threads clean to prevent fluid contamination. Thread the connector into the female port finger-tight, then tighten with an open-end wrench 2 to 3 full turns until snug.

Bodies are machined from ASTM B16 C36000 free-cutting brass or hot-forged from BS 218 / CW617N brass. Every manufacturing batch undergoes 100% pneumatic bubble testing at 10 bar and coordinate measuring inspection of threads, delivered with an authentic EN 10204 Type 3.1 Mill Test Certificate.