Conax’s Haynes® 188, a cobalt-base alloy, offers high temperature strength and oxidation resistance, reducing change-out costs and downtime.

Industry: Manufacturing – Plumbing Fixtures
Application: Direct Immersion in Natural Gas Burner Flame

Customer Requirement: Customer required Type K dual thermocouples to monitor the reducing atmosphere of a natural gas burner used to heat copper turbine in the formation of plumbing features such as J-traps. The process temperatures range from 1600°F to 1700°F (870 °C to 927°C). The customer had been using an Inconel® 600 sheath, but the sheath would oxidize in two to four months.

Conax Design Solution: Conax initially tried a ceramic sheath, but the propagation of the burner gases through the ceramic tubewell caused junction failure. Conax then developed an assembly using a Haynes® 188 sheath. Haynes® 188 is a cobalt-base alloy that offers high temperature strength and oxidation resistance in temperatures up to 2100°F (1150°C). The Haynes® 188 extended the service life of these assemblies by more than six months, reducing change-out costs and downtime due to sensor failure.