High Tech Metal Seals

High Tech Metal Seals (HTMS) is a privately owned company, founded in 1999 by a group of sealing specialists with a combined experience of more than 100 years.

We design and manufacture elastic or resilient metal seals at our Belgian manufacturing plant in Mechelen. Our metal seals are unparalleled in terms of size, shape and performance across a broad spectrum of sealing applications.

  • Metal O-Seal
  • Spring Energised Metal O-Seal
  • Metal C-Seal
  • Spring Energised Metal C-Seal
  • Spring Energised Aluminum C-Seal
  • Metal Oysterseal®
  • Metal Commaseal®

HTMS’ resilient metal seals are used in a wide variety of applications where normal seals cannot cope with extremes of temperature, pressure, medium or combinations thereof.


HTMS specialises in metallic seals, serving all markets including aerospace, nuclear, oil & gas (both subsea and topside), automotive, industrial, medical…


HTMS is dedicated to produce resilient metal seals under the most stringent quality procedures. The company is ISO 9001, AS 9100 and ISO 14001 certified.


  • 100% LP test on O Ring seal welds
  • X-ray of weld area on request
  • Fully integrated Helium leak test facility
  • Hydrostatic pressure testing up to 90 MPa
  • Seating load and spring back measurement equipment
  • XRF on plating layers
  • CNC optical measurement for in-line and end control


  • More than 100 years of experience
  • In-house testing
  • R&D for new products
  • Close cooperation with universities
  • Development of new production methods and new sealing solutions


  • Short lead times
  • Procedure for rush production
  • Quick response time
  • Custom-made sealing solutions
  • Dedicated staff

Production Capabilities

  • Seal diameter range from 5 mm up to 4 m
  • Cross sections from 0.79 mm up to 12.70 mm
  • Non-standard cross sections available on request
  • Shaped seals, race track, rectangular and other shapes on request
  • Tailor-made seals as per customer specifi cations
  • In-house plating and coating facilities
  • In-house heat treatment facilities
  • In-house laboratory for testing purposes

General Metal Seal Properties

  • Unlimited shelf life
  • Radiation and corrosion resistance
  • Low load compared to flat gaskets, RTJ's
  • High elastic recovery over an extended service life
  • Temperature from -270 °C up to +650 °C (higher temperatures on request)
  • Pressure from ultra-high vacuum up to +500 MPa
  • Leakage rates better than 10-10 Pa.m³/s possible with proper design
  • No explosive decompression issues

For specific seal selection contact HTMS