Sealing O-ring

Seals, o-rings, and valve membranes must be manufactured out of polymers that are resistant to thermal sterilization and to the bases and acids used in the biopharmaceutical industry. When in contact with the product, the elastomers employed must additionally present the following safety characteristics the rates of release of polymer components must be low and remain below well-established threshold levels the components released must be innocuous to human health, according to rules previously established. 

Use Diaphragms, gaskets and seals, O-rings, hose, coated fabrics, wire and cable, and insulating components for electrical and electronic parts. 

Fluorel . [3M] Fluoroelastomers for extrusion, inj., compression, and transfer moldings, fuel line hose, seals, o-rings, calendered sheet, rolls. 

Nipol AR. [Zeon] Acrylic rubber used for seals, o-rings, gaskets, automotive parts, etc. 

Hydrin . [Zeon] ichlwdiydrin/ethyl-ene oxide copdymers or tttpolymers elastomo for fuel pump daphragms, pipe gaskets, fuel h, motm mounts, rolls, adhesives, sponge goods, boots, seals, o-rings, bladders. 

O-ring seals are less common in HPLC columns, but are quite feanUe. The main issue is the compatibility of the O-ring material with the mobile phase. Incompatible O-rings can disintegrate resulting in a sudden loss of the seal O-rings made of fluorocarbon-based rubbers such as Kalrez or Chemraz have a suffidently broad solvent compatibility to be useful with all molnle phases commonly used in HPLC. 

The principal applications for ETFE are found in such products as gaskets, packings, and seals (O-rings, lip and X-rings) in areas where corrosion is a problem. The material is also used for sleeve, split cmled, and thrust bearings, and for bearing pads for pipe and equipment support where expansion and contraction or movement may occiu-. 

Uses Lubricant, EP agent for chem., aerospace, hydraulic fluids, metalworking, nuclear, pulp/paper, other industries chemical piping chem.-resist. seals/o-rings gaskets tank linings wire/cable insulation mold... 

Plug and butterfly valves do not have any axial stem displacement and use various types of sealing O-rings, if the temperature is lower than 200°C. These t q)es of valves have other limitations such as a susceptibility to develop leak paths and to undergo blockage. 

Parker Seals O-Ring Handbook, Parker Hannifin Corporation, Lexington, KY, 1977. 

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