Rubber Gaskets
A rubber gasket is placed in between two objects in order to prevent leakage of any kind of the pressurized or not pressurized media. the gasket requires resistance against media and temperature within the range of the given application.
requirements for a gasket are:
- good compressibility and face adaptability
- good recovery
- strength
- limited relaxation
- chemical resistance
- temperature resistance
Metallic & Semi-metallic gaskets
A metallic or semi-metallic gasket system.
- high sealing pressure at the metal corrugation
- high blow out resistance
- in case of metal to metal, a perfect flange surface is required
A semi-metallic gasket system, which consist of:
centering (outer) ring made of special steel
cam-profiled (sealing) ring made of special steel
soft covering layer made of graphite, ptfe, ..
typical applications: pipelines, heat exchanger.
A semi-metallic gasket system. also called per tradition heat exchanger gaskets, which indicates the typical application. the gasket consists of a soft filler with a metal cover. the metal jacket provides compressive strength and blow out resistance. the filler provides compressibility and resilience.
- robust, can be handled and installed without special care
- wide range of shapes
- requires a good flange surface because of metal to metal sealing
metal cover: carbon steel, SS, monel, copper, etc.
fillers: CSF, expanded graphite etc.
Metallic gaskets, which are manufactured from a variety of metals and alloys, usually oval or octagonal in cross-section, depending on the flange design.ring joints are designed to serve at high pressure and high temperature applications.
standard metals: soft iron, LC carbon, range of SS; other materials on demand.
A semi-metallic gasket system, consisting of:
- centering (outer) ring made of special steel
- a spiral wound V-shaped metal strip filled with graphite, ptfe, ceramic,
mica, ....
- inner ring made of special steel
- covers a wide pressure and temperature range and is therefore a real multi purpose (universal) gasket
- the spiral wound gasket does not stick to the flange surface and can be easy removed
- has a good shelve life and requires no special care during handling and installation
- good resilience because of the V-shaped metal strips
- very popular gasket system and therefore good availability
standard sizes: ASME/ANSI, BS, DIN, non standard sizes
standard fillers: expanded graphite, PTFE
standard metals: low carbon steel (paint or zinc plated finish), SS 316L, SS 304, SS 321,
monel and other exotic materials are on demand
Non-metallic gaskets
Only graphite with a purity of elemental carbon can be used. graphite gaskets usually are reinforced with a stainless steel insert. Important is the design of the reinforcement. currently common are smooth metal, tanged metal and expanded metal inserts.
Graphite has got a superior chemical resistance against a wide range of media. it can be used up to 450-550°C application temperature. with expanded metal graphite gaskets even metallic gaskets can be replaced in many applications.
PTFE provides an outstanding chemical resistance. PTFE is attacked only by molten alkali metals and fluorine gas and has excellent anti-stick and dielectric properties.
- very dense sealing material
- adapts perfect to the flange
- very good chemical resistance available in all standards and as per client requirements
| acrylonitrile-butadiene rubber | NBR | −30°C ....100°C | improved chemical resistance and temperature capabilities to neoprene. good resistance to hydrocarbons and oils. not suitable for chlorinated hydrocarbons, esters, ketones and strong oxidising agents. |
|---|---|---|---|
| silicone | VMQ, PVMQ |
−60°C ....200°C | excellent temperature properties, and unaffected by ozone and sunlight.not suitable for many hydrocarbons and steam. |
| chlorbutadiene rubber | CR | −45°C ....100°C | excellent resistance to oils, ozone and weathering. suitable for moderate acids, alkalis, salt solutions, petroleum, solvents, oils and fuels. it is not recommended for strong acids or hydrocarbons |
| natural rubber | NR | −60°C ....80°C | excellent for recovery properties. good resistance to most inorganic salts, mild acids and alkal is.not recommended for oils and solvents, or where exposure to ozone, oxygen or sunlight is prominent. |
| ethylene propylene diene rubber | EPDM | −50°C ....150°C | elastomer which offers good resistance to ozone, steam, strong acids and alkalis, but is not suitable for solvents and aromatic hydrocarbons. |
| butyl rubber | IIR | −40°C ....150°C | an elastomer offering good resistance to ozone and gas permeation.suitable for mild acids, alkalis and esters, but little resistance to oils and fuels. |
| styrene butadiene rubber | SBR | −50°C ....100°C | suitable for use with weak organic acids and moderate chemicals. not suitable for strong acids, most hydrocarbons or ozone. |
| fluoroelastomer | FKM | −20°C ....200°C | excellent for oils and greases, fulls and aliphatic as well as aromatic hydrocarbons, some fire retardant hydraulic liquids and synthetic aviation engine oils. |
Types for Gaskets
- Cork Bonded Nitrile/Neoprene
- Silicone Sponge
- Neoprene Sponge / Neoprene
- Nylon-reinforced gaskets / Metal reinforced gaskets
- Flange gaskets of all standards and non standards
- Vessel gaskets upto 10000 MM outer dia
- Pressure gaskets, Alpha level gaskets and all types of gaskets