WhoshouldIsee Tracks High-Temperature Bellows for CHP Power Station - Teconnex Bellows

High-Temperature Bellows for CHP Power Station

Sector: Energy Services

Background

An international energy and services company at the centre of the UK energy industry required a high-performance axial expansion joint for the heat recovery system of one of their Combined Heat and Power (CHP) stations. 

Challenge

The expansion joint needed to: 

  • Handle high temperatures of up to 680°C and axial movement of ±50 mm
  • Perform reliably across more than 560,000 operating cycles
  • Reduce flange outlet temperatures to below 60°C through effective insulation
  • Meet strict quality and testing standards for high-integrity pressure systems

Solution

Teconnex Bellows provided a bespoke single axial bellow to meet these specifications:

  • Thermal Performance: The bellows featured a 2-ply 321 stainless steel membrane, chosen for its high temperature strength and fatigue resistance. 
  • Thermal Insulation: An internal insulator layer was included to protect surrounding components and limit the outlet flange temperature. 
  • Durable Construction: Flanges, inner cone, and connecting pipework were made from P235GH carbon steel, a pressure-grade material suited for high-temperature applications. 

Technical Data

  • Type: Single Axial Bellows
  • Design Pressure: 0.5 Barg
  • Design Temperature: 680°C
  • Axial Movement: ±50 mm
  • Design Cycles: 560,253
  • Bellows Membrane Material: 2-ply 321 Stainless Steel
  • Flanges, Pipe & Inner Cone Material: P235GH Carbon Steel
  • Insulation: Internal, designed to maintain flange outlet temperature <60°C
  • Testing & Certification:
    • 100% Radiographic inspection of membrane butt welds to ASME V
    • 100% LPI inspection of all attachment welds
    • Pneumatic pressure testing at 10 psig
    • Full 3.1 material certification for all parts
    • Certified welding procedures and personnel (WPS & WPQR)

Result

This custom expansion joint now enables the safe and efficient operation of the CHP plant’s heat recovery system. By combining high-performance materials with precision design and insulation, Teconnex Bellows helped the client meet stringent temperature, movement, and safety requirements, ensuring long-term reliability in a demanding thermal environment.