Product Description

Mueller Steam Specialty — the steam-service specialty valve and separator manufacturer — supplied inline steam separators with integral drain traps to U.S. industrial, utility, and marine steam systems throughout the mid-20th century. Steam separators are installed upstream of turbines, at main steam distribution headers, and at process-steam takeoffs to remove entrained condensate and particulate before high-value or sensitive downstream service. Mueller steam separator drain trap assemblies — the combined separator body plus integral trap — relied on asbestos-bearing packing, gaskets, and baffle-seal elements during the asbestos era.

Plaintiffs alleged in publicly filed U.S. asbestos personal-injury and wrongful-death litigation that Mueller Steam Specialty separator/drain-trap sealing systems included:

  • Compressed asbestos-fiber (CAF) sheet gaskets at the separator body-cover flanged joint
  • Asbestos-braided gland packing around the drain-trap discharge-valve stem
  • Asbestos baffle-seal elements at the separator internal baffle-plate mounting
  • Asbestos-fiber sheet gaskets at the integral drain-trap body-cover joint and discharge nozzle
  • Asbestos-cord thread sealing on the drain and vent connections

These packing and gasket elements were disturbed during separator internal cleaning (removal of accumulated scale and particulate from the separator baffle plates), during scheduled drain-trap rebuilds, during body-cover gasket replacement after cover removal for internal inspection, and during in-service trap-failure diagnosis. Steamfitters and turbine mechanics routinely opened Mueller separator assemblies, scraped baked-on gasket residue, and repacked drain-trap discharge valves — a recurring maintenance cycle across the operating life of the steam system.

Mueller Steam Specialty has been named as a Manufacturer Defendant in publicly filed U.S. asbestos personal-injury and wrongful-death litigation.

Workers Exposed

  • Steamfitters (UA) rebuilding Mueller steam separator drain-trap assemblies on industrial and utility steam systems
  • Pipefitters (UA) replacing separator body-cover and discharge-nozzle gaskets during in-line repair
  • Power plant maintenance mechanics opening separator internals for baffle-plate cleaning during scheduled outages
  • Turbine mechanics replacing packing and gaskets on separators feeding turbine inlets during turbine overhaul
  • Bystander trades in turbine halls, boiler houses, and process-steam corridors during separator rebuild work

Scraping CAF gasket residue from Mueller separator body-cover sealing faces and pick-tooling old braided packing from drain-trap valve stuffing boxes were among the fiber-release activities alleged in publicly filed litigation.