TRD Toroid
expansion joints

TRD Toroid<br/>
expansion joints For a larger view, please mouseover the image.
For a larger view, please mouseover the image.
Typical toroid bellows cross section

Item Description
1 Bellows
2 Duct
3 Cover clip
4 Cover
5 Liner
  • High pressure heat exchanger applications.
  • Designed to ASME BPVC Section VIII, Division 1, Appendix 26.
  • Additionally, can be manufactured according to the European PED (Pressure Equipment Directive).
  • Highly-engineered expansion joints.
  • Reliable operation in critical applications.
  • Economical alternative to reinforced bellows.
Diameter: 400 mm (16”) to 4,250 mm (170”)
Process temperature: -190 °C (-310 °F) to 650 °C (1,200 °F)
Pressure (dependent on the diameter): FV to 138 bar (2,000 PSI)
Maximum total axial movement (compression and extension combined): 25 mm (1”)
Permitted lateral movement: 0 mm (0”)
Permitted angular movement: 0°
  • Typical bellows materials: Inconel® 625 Gr. 1, 304 stainless steel. Other materials on request.
  • Bellows basics: single or multi-ply (depending on the application). Formed by punch mandrel, thin-wall ply thickness ≤1.5 mm (0.060”). Subsequently, toroidal cross-section achieved through hydraulic pressurization.
  • Typical duct: A266N Gr. 2, 25 .. 125 mm (1 .. 5”). Other materials on request.
  • Cover material options: carbon steel, stainless steel.
  • ASME Section VIII, Division 1, U (unfired) pressure vessel certificate
  • European Pressure Equipment Directive (PED) 97/23/CE
  • Expansion Joint Manufacturers Association (EJMA)
  • ISO 9001:2008
  • Chemical industry
  • Power plant technology
  • Process industry
  • Refining technology
  • Any expansion joint within a high pressure system that must conform to ASME BPVC Section VIII, Division 1.
  • Heat exchangers
    (primarily shell and tube or floating head).
  • Chemical reactors
Metal expansion joints are used in pipelines to compensate for thermal growth, typically in applications with high internal temperatures; or to prevent vibrations from being transmitted beyond the expansion joint.
Standard quality control and testing:
  • Full x-ray of bellows longitudinal seam weld before formation of convolutions.
  • Full dye penetrant test of bellows longitudinal seam weld inside and outside before and after forming of convolutions.
  • 100 % dye penetrant test of bellows attachment welds.
  • Hydrotest
  • Third-party inspection by an ASME-certified inspector

Additional quality control and testing options:
  • Impact testing of weld ends
  • PMI (Positive Material Identification)
  • Ultrasound weld tests
  • Helium leak check
  • Hardness test
  • Magnetic particle examination

  • Skilled field service teams can provide site support.
  • Experienced supervision by our field service personnel available.