Flue Duct Expansion Joints

Style 8400 flue ducts are available in round, rectangular, or square configurations; as belt type (without flanges) or U-type (flanged); with virtually no size restrictions. Garlock also provides on-site vulcanizations for flue ducts that require splicing into position, due to obstructions or interferences that prevent continuous construction installations.

Regional Availability Restrictions: 
Not available in Europe


  • Max. Temperature: 400°F / 204°C


Rectangular / Square Flue Ducts

  • Stanard face-to-face dimensions: typically 6in / 152 mm, 9in / 229 mm, or 12in / 305 mm
  • Contact Garlock for non-standard face-to-face dimensions and movement capabilities

Round Flue Ducts

  • Supplied in any size, with or without flanges or arch
  • Variety of materials available: neoprene, chlorobutyl, fluoroeslastomer, nitrile, EPDM, CSM, FDA neoprene, FDA EPDM, or natural/gum rubber
  • Movement capabilities depend on expansion joint size and arch configuration

Belt-Type Flue Ducts

  • Supplied in any size, without flanges, with or without an arch
  • Available in the same materials as round flue ducts
  • Movement capabilities depend on installation width and arch configuration
  • Supplied open-ended (wraparound) or continuous to fit over ducting


For more info on these materials click here.

  • ABRA-LINE™: +180°F  (+80°C)
  • ABRA-SHIELD™: +300°F (+150°C)
  • Natural Rubber: +180°F (+80°C)
  • FKM (Fluoroelastomer): +400°F (+205°C)
  • CSM: +250°F (+120°C)
  • EPDM/FDA EPDM: +300°F (+150°C)
  • HNBR (Hydrogenated Nitrile): +300°F (+150°C)
  • Nitrile/FDA Nitrile: +250°F (+120°C)
  • Chlorobutyl (Standard): +250°F (+120°C)
  • Neoprene/FDA Neoprene: +250°F (+120°C)
Find SDS and MSDS Documents