gasketing

Gasketing refers to the use of a gasket, a sealing element placed between mating surfaces to prevent the leakage of fluids or gases and to accommodate surface irregularities. Gaskets are used on static joints and can provide insulation, dampening, and a compensating seal for imperfect flange faces or fittings.

Gaskets come in a range of materials and configurations. Non-metallic options include elastomers such as nitrile, EPDM, silicone, and fluorocarbon compounds, as well as PTFE, compressed fibers, graphite, and cork. Metallic gaskets include soft metals and metal-reinforced designs. Common forms include sheet gaskets cut to fit a flange, ring gaskets for circular joints, O-rings for grooves, and spiral-wound or composite gaskets that combine metal and filler materials. Graphite and PTFE are favored for chemical resistance in many services.

Design and selection considerations focus on flange type and size, operating pressure and temperature, the fluid’s chemical compatibility, gasket thickness, and seating stress. Surface finish and flatness, bolt preload, and whether the gasket is intended for single use or reuse also influence choice. Standards from organizations such as ASME, DIN, and ISO guide gasket selection, testing, and installation practices.

Installation and maintenance emphasize clean, undamaged mating surfaces, correct gasket sizing, and even bolt loading to avoid leaks. Gaskets should not be reused after compression, and damaged or degraded gaskets should be replaced. Proper lubrication (where appropriate) and adherence to manufacturer or standard guidelines improve seal integrity.

Applications span piping flanges in oil and gas, chemical processing, power generation, water treatment, and HVAC systems. Gasket performance can decline due to creep, relaxation, or chemical attack, making timely inspection and replacement essential.