Metal gaskets are usually replaced, not reused, because compression changes the gasket geometry, the surface may develop micro-damage that compromises the seal, and they rely on plastic deformation to seal. Once deformed, they will not reseal correctly. They may be reused only if the manufacturer specifically approves it, there are no dents, scratches, or deformation, and torque specs can still be reached safely. For critical service, never reuse a metal gasket.

Soft seats made from materials such as Teflon, plastic, nylon, or rubber provide tight shutoff (bubble-tight), low torque, and lower temperature capability, typically under 232°C, but they are vulnerable to abrasion. Metal seats made from stainless steel, carbon steel, nickel, or hard-coated alloys withstand high temperature, up to about 500–700°C depending on design, resist abrasion, perform well under high cycling or steam, provide durable metal-to-metal sealing, handle high pressure, and are often required for fire-safe applications.

Disc springs provide a controlled preload that keeps metal seats pressed firmly against the ball or plug without requiring excessive torque. They automatically compensate for thermal expansion, pressure changes, and cycling, which supports a consistent seal over time. This improves shutoff, reduces wear, and helps prevent leakage even in demanding services such as high-temperature steam or high-cycle operations.

General assembly guidelines include verifying dimensions such as ID, OD, thickness, and groove depth; verifying the correct order of parts (spring, spacer, then seat ring); lightly lubricating metal-to-metal interfaces if the manufacturer recommends it; making sure springs or disc washers are oriented correctly for the load direction; installing the seat ring without forcing or misalignment; torquing body fasteners using the recommended sequence and values; and performing a leak test after assembly.

Engineers consider surface finish and coatings, clearances for thermal expansion, load distribution, and operating torque. Torque that is too tight can cause wear. The goal is to achieve maximum sealing force with minimum friction and predictable wear.