BONLOK is a permanent pipe connection equivalent to a welded joint. Based on Swage technology, which utilizing two 360° metal to metal sealing rings (no o-rings). Perfect design, exquisite Swiss technology and superior quality make BONLOK widely used around the world. BONLOK is designed to be convenient, highly-effective, safe and reliable and is certified by all major international classification societies.


Industrial Uses:

  • Offshore Oil / Gas;
  • Ship Building;
  • Mining;
  • Petroleum / Chemical Industry;
  • Plant Constructions;
  • Machinery Construction;
  • Hospital Installation;
  • Food/ Dairy/ Sugar Processing Industry;
  • Nuclear Reactors

Application Areas:

  • Fire suppression;
  • Sprinkler Systems;
  • Compressed Air Systems;
  • Heating Systems;
  • Water Piping;
  • Sewage Systems;
  • High-pressure Washing;
  • Hydraulic Fluids
  • Bilge & Ballast piping
  • Vent & Sounding piping
  • Salt Water Cooling piping

Swage Technology: What is it?

Swaging is the controlled uniform reduction of the fitting end over the tube whereby forces are applied equally; 360 degrees around the fitting. The result of swaging creates a permanent connection between the fitting and tubing by plastically deforming them together as an assembly.

The swaging process also controls the elastic rebound of the tube within the fitting bore to create a sound mechanical connection and permanent fluid containment seal.

During installation, the driver placed over the fitting body swages the body onto the pipe or tube surface, compressing the pipe/tube wall, first elastically and then plastically. The pipe/tube wall resists this swaging action, generating high unit compressive loads at the contact points between narrow sealing lands inside the fitting body and the pipe/tube surface (RINGS).

These contact stresses are sufficiently high to plastically yield the pipe/tube surface under the sealing lands, forming a perfect 360° circumferential, permanent, metal-to-metal seal between the pipe/tube and the fitting body. The driver, which experiences a small increase in diameter (elastic strain) during installation, exerts an elastic, radial preload on the metallic seals for the life of the connection.

Cost Savings: Bonlok vs Weldingbonlok-fitting-cutaway-schematic

  • 70% Saving of time on installation and inspection
  • No need for Costly Welding Process
    • No Pipe Alignment
    • No Beveling
    • No Heat or Fire
    • No X-Ray or NDT
    • No Pickling
    • No Flushing
  • No need for specialized labour
  • Less Expense for Human Resources


Product Materials

Fittings Produced in:

  • Zinc coated Carbon Steel St45
  • Stainless Steel 304
  • Stainless Steel 316L

Custom materials are available via special order.

Size Ranges

Metric, from 4mm to 80mm

Imperial, 1/4″ to 6″

Bonlok Pressure Test

Pressure Burst Trial Example:Pressure (3)

The Bonlok fitting is designed to withstand a working pressure (PN) higher than the one of the pipe in use.

Trial Example using small diameter pipe size and wall thickness

  • Sample:  Bonlok Standard Coupling
  • Pipe OD: 3/8” (17.2 mm)
  • Wall thickness:  2.5 mm
  • Pipe material:  Carbon Steel



Pressure Burst Trial Result:

Cracking Pressure :Max.-Pressure-565-44517,229 psi (118.8 MPa)

A maximum pressure of 118.8MPa (17230psi) was borne by Bonlok pipe fitting O.D.17.2mm during the test. The pipe burst, ending the test, while the Bonlok fitting with connected pipe maintained integrity.

Bonlok Press Kit RangePICBonlokNewP-60Window1

  • Bonlok Manufacture 12 Press Kits, that range from 1/4″ to 6″ (4-168mm)

  • Compact and Lightweight hydraulic installation tools only require one plan of access on fitting application



Bonlok Press ToolsPicBonlokNewP-60window2

  • Cost effective system

  • Fast and easy to use hydraulic installation

  • Installs quickly in adverse conditions

  • No contaminants






Find out more Technical Information

Review the technical installation guidelines for fast and easy installation and use.

Review the working pressures and installation manual