Open steam cure

This term is synonymous with vulcanisation but is generally applied to the factory methods of vulcanising mbber products, e.g., press curing, open steam curing, cold curing. 

In open steam curing that period of time during which the temperature is raised gradually from room temperature to the actual curing temperature. 

Water in the gaseous state it is a convenient source of heat widely used in the curing of rubber products. See Open-Steam Curing, Press Curing. Steam is really a colourless gas and what is usually termed steam (issuing from an autoclave, a press, thermometer bleed pipe, etc.) is really droplets of water which result from the steam meeting the cooler air of the atmosphere. Steam Trap... 

Some of the technical properties of ebonite are appreciably affected by the method of cure. In open steam curing, the external pressure is limited to a few atmospheres of steam pressure. The direct... 

In open steam cure of linings and tubes and rods it is important that the ebonite does not flatten under self weight. Addition of ebonite dust and mineral fillers or reclaimed rubber increases the stiffness of the green stock and reduces the tendency for loss of shape. 

Autoclave curing Open steam curing Hot water curing Self-vulcanizing Cold bond lining and... 

Open steam cure - A method of vulcanization in which the steam is in direct contact with the product being vulcanized at atmospheric pressure. 

Chem. Desaip. Cone. aq. disp. of PTFE particles CAS 9002-84-0 EINECS/ELINCS 204-126-9 Uses Release coating for hot molds used to form mbber and plastic parts antistick coating for pan or open-steam cure of hose and other extmsions antistick coating to reduce buildup of compds. on rolls, cutting, and forming tools, and other process equip. 

Vulcanization may be by moulding in a press, hot-air or open-steam methods, although the open-steam cured rubbers are often softer than the others. Low-temperature vulcanization (140-160°C) gives vulcanizates with better physical strength than do higher temperatures (> 160°C). 

Open Steam Curing - Open steam curing is used in the production of hose, wire and cable, and other extruded articles such as tubing or channel stripping. With this method, the artiele may be in direct contact with the steam, wrapped with fabric tape, encased in an extruded covering of lead, or supported by soapstone in a shielded pan. Equipment m eonsist of a jacketed autoclave or a closed chamber in which the articles are plaeed and steam is introduced. 

Compression molding Transfer molding Injection molding CV cure in steam Open steam cure... 

Both wrapped and open steam cures acceptable... 

In curing thick articles in open steam it is sometimes necessary to reduce the temperature of cure at the end of the hold period at a slow yet uniform rate. This part of the cure schedule is the drop . 

A preliminary or pre-cure given to a product or part of a product, e.g., a moulding may be given a semi-cure in a press and the cure completed in open steam a thick section of a product may be semi-cured before assembly to the product a component may be semi-cured to reduce the flow during the subsequent vulcanisation of the product. 

The process of controlled, gentle warming of unvulcanised calendered sheet rubber to reduce its anisotropy and prevent subsequent distortion of articles made from the sheet and cured by embedding in chalk in open steam. 

An obsolete process for reheading pneumatic tyres. The vulcanisation of the new head rubber is not done in a mould but by the open steam method in an autoclave, and the deshed pattern is cut on the head after cure. 

No one curing process posesses all the virtues and those which may appear to be most desirable may be rejected on grounds of initial cost and maintenance of the equipment. For example even an autoclave curable rubber lined vessel can be cured in open steam at atmospheric pressure and this method can be adopted while the autoclave is down for repairs and maintenance. 

Steam cure (open) - A method of vulcanizing rubber parts by exposing them directly to steam. 

For adhering the Hypalon sheet to the metal surface, invariably a tie-gum or tie-solution in toluene can be used over the isocynate coat (i.e., Chemlok 205) for better integrated bond with the metal. The technique of application of Hypalon lining is almost same as that of Neoprene. The curing in autoclave, in open steam or hot water is also similar to that of Neoprene. 

The Zeonet system does provide very good compression set without post-cure, good bin stability, reasonably fast cure rates, and it may be cured in open steam. The vulcanizates have good water and corrosion resistance. 

Transmission Oil Cooler Hose compounds are shown in Table 5.24 in which two non-post-cure systems are given. Both the NPC-25 and Zeonet system provides low compression set without post-cure. The temperature of the NPC-25 compound during processing must NOT exceed 85°C, as measured in the stock. During vulcanization, a moisture barrier such as Mylar film should be wrapped on under the nylon tape. The Zeonet cure mechanism also does not require a post-cure and it has the added advantage that it may be used in open steam without a moisture barrier. 

Higher-filler loadings are advantageous to stiffen the low-viscosity EVM polymer. Higher-viscosity grades of EVM should be used if possible. If curing in open steam, add 3-5 pphr of a polycarbodiimide, such as Rhenogran P 50. 

Elongation at break (%) Adhesion to mild steel shotblasted, degreased, cured in open steam 60 min at 0-28 MPa, jaw separation rate Scmimin) Bond strength (kN/m) 680... 

Laminates are pressed in steam-heated, multiple-opening presses. Each opening may contain a book of as many as ten laminates pressed against pohshed steel plates. Curing conditions are 20—30 min at about 150°C under a pressure of about 6900 kPa (1000 psi). 

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