Metal Bellows Seal Application: Fuel Pump

Background

The pump for a commercial aircraft had an existing carbon face seal experiencing high leakage and seal failures. Technetics Qualiseal® Technology was employed to find a solution.

Operating Conditions

  • High speed (27,000 rpm)
  • Dry running (no lubrication)
  • 12.5 psid

Determining Cause and Failure Modes

  • Seal testing and Qualiseal® Technology FEA model indicated temperatures up to 650°F
  • Current secondary seal taking a set due to high temperature
  • Possible carbon resin exudation due to high temperature

Technetics Qualiseal® Technology Solution

  • Designed a metal bellows seal assembly with a high-temperature carbon grade
  • Sealed application and satisfied extreme temperature requirements