Closures, sealing

With a batch process, such as hot isostatic compaction (HIP), heat exchange as used in a continuous reactor is not possible, and it is common practice to provide a furnace within the pressure vessel which is thermally insulated to ensure that the temperature of the vessel does not rise above 300°C. Most HIP operations involve gas pressures in the range 70—200 MPa (10—29,000 psi) and temperatures of 1250—2000°C, occasionally 2250°C (74). The pressure vessel may have a bore diameter from 27 to 1524 mm (75) and is nearly always provided with threaded closures sealed with O-rings made of elastomer provided the temperature is low enough. 

PVC closure seals for jars Di-(2-ethylhexyl) phthalate Di-iso-decyl phthalate Di-iso-octyl phthalate... 

Nickel Alloys Alloy C-4 (16 Cr, 16 Mo, Balance Ni) and alloy C-276 (16 Cr, 16 Mo, 3.5 W, 5 Fe, balance Ni) have been used for closure seals on cryogenic gas cylinders because the alloys retain all their ductility down to -327°C (—557°F). The impact strength at liquid nitrogen temperatures is the same as that at room temperature. 

Ethylene and initiator are fed through the top closure which also contains the bursting-disc ports. The autoclave is equipped with a stirrer driven by an external or internal electric motor. The external motor can be arranged at the top or at the bottom closure, sealed with a number... 

The volume of media filled into the containers need not be the routine fill volume for the container. It should be of sufficient volume to contact the container-closure seal surfaces and sufficiently large to allow for easy inspection of the filled units postincubation. Despite the lower fill volume, the speed of filling should match that used for the routine filling of the product being simulated. Smaller containers should not be over-filled as sufficient air must be available in the container headspace to support the growth of aerobic organisms and problems have been encountered where the liquid media essentially fills the entire container. 

Flame-sealed containers Closure-sealed containers... 

Nominal size (in mL) Flame-sealed containers (%) Closure-sealed containers (%)... 

Container/closure seal integrity has been reviewed by the Parenteral Drug Association (1983) and the Parenteral Society (1992). Variation in the overall height of the combined vial and closure will result in different closure-seal forces being applied at the crimping head. Quality control tests are proposed such as the dye intrusion challenge, liquid loss or bacterial... 

Connor, J. T. (1983). In-process verification of closure seal integrity. Journal of Parenteral Science and Technology 37 14-19. 

Vinylidene dichloride film PVC closure seals for jars... 

Applications are also found in other industries as diaphragms, flexible tubing, closures, seals, gaskets, convoluted tubing, and hose, particularly in the chemical, cryogenic, and aerospace industries. 

Uses Dry cleaning detergent internal lubricant, slip agent for plastics, coatings, films foam/visc. stabilizer water repellent for textiles emulsifier, emulsion stabilizer, surfactant, vise, control agent in cosmetics in closure-sealing gaskets for food containers defoamer in food-contact paper/paperboard... 

Uses Plasticizer for PVC, PS, cellulosics, paints vehicle for pigment dispersions plasticizer for side seam cements for food-contact containers syn. lubricant basestock pharmaceutical pkg. in food-pkg. adhesives in closure-sealing gaskets for food containers plasticizer in food-contact rubber articles for repeated use in surf, lubricants for mfg. of food-contact metallic articles... 

Uses Plasticizer/stabilizer for epoxy, PVC, paints plasticizer/synergist for PVC heat stabilizers plasticizer in food-contact polymers coupling agent for S/B block copolymers pigment dispersant in PVC-P in closure-sealing gaskets for food containers in food-contact polysulfide polymer/polyepoxy resins... 

Uses Chemical blowing agent for sponge rubber, expanded plastics, esp. EVA copolymers, LDPE, and PVC for cellular cable insulation, rug underlay, gaskets, upholstery material, adhesives food-contact rubber articles for repeated use in closure-sealing gaskets for food containers... 

Uses Emulsifier, dispersant for cosmetics, pharmaceuticals, textiles, leather, industrial applies. lubricant dye assistant leveling agent for polyester food-pkg. adhesives defoamer in food-contact paper/pa-perboard in resinous/poiymeric food-contact coatings in closure-sealing gaskets for food containers in food-contact textiles Regulatory FDA 21CFR 175.105,175.300,176.210,177.1210,177.2800 Manuf/Distrib. A E Connock... 

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