Types of Asbestos Sealing Products
| Product Type | Description | Asbestos Content | Major Brands |
|---|---|---|---|
| Sheet gasket / compressed asbestos fiber (CAF) | Flat sheet asbestos material cut to fit flanges; the most common industrial gasket type | 80–85% chrysotile/crocidolite | Garlock, Flexitallic, Crane Packing, John Crane |
| Spiral-wound gaskets | Metal and asbestos filler wound in spiral alternating layers; used in high-pressure flanges | Asbestos filler between metal windings | Flexitallic (market leader), Garlock, Lamons |
| Ring gaskets | Solid compressed asbestos ring; used in pipe flanges and valve bonnets | 75–95% asbestos | Garlock, Armstrong, various |
| Valve packing rope | Braided asbestos rope compressed around valve stems to prevent leakage | 80–100% asbestos | Palmetto (Anchor Packing), Crane, John Crane |
| Pump and valve packing rings | Pre-formed asbestos packing rings for pump stuffing boxes and valve bodies | High asbestos content | John Crane, Garlock, Flexitallic |
| Rope and tape | Woven or braided asbestos rope used for sealing, wrapping, and high-temperature applications | Up to 100% asbestos | Various — Atlas Asbestos, National Asbestos |
How Gasket Work Exposed Workers
Gasket and packing work created asbestos exposure in several ways:
- Cutting sheet gasket material: Workers cut asbestos sheet gasket to fit flanges using knives, dies, or power tools. Power cutting released the most fiber; hand cutting was also hazardous with high-asbestos-content materials.
- Removing old gaskets: Baked and compressed gaskets had to be scraped or wire-brushed from flanges during maintenance. Scraping dried asbestos gasket material was a significant exposure source.
- Handling packing rope: Cutting packing rope to length and compressing it into stuffing boxes released fibers from the braided asbestos material.
- Bystander exposure in refineries and plants: Turnaround maintenance — periods of intensive planned maintenance — involved dozens of pipefitters simultaneously replacing gaskets throughout a unit, creating elevated ambient fiber concentrations for all workers in the area.
Key Trust Funds for Gasket Exposure
- Garlock Sealing Technologies Asbestos Trust — Garlock was the dominant compressed asbestos fiber sheet gasket manufacturer in the U.S.
- Flexitallic Asbestos Personal Injury Trust — Spiral-wound gaskets used throughout oil and gas, power generation, and chemical processing
- Anchor Packing / Pneumo Abex Trust — Palmetto brand valve packing rope
- John Crane (ongoing litigation) — Major pump and valve packing manufacturer, subject to substantial asbestos litigation
- Armstrong World Industries Asbestos Personal Injury Settlement Trust
Pipefitter or Industrial Worker?
Gasket and packing trusts may provide compensation. A mesothelioma attorney can identify every applicable trust from your work history.