Steam hose compound

Use Tire carcasses and linings, especially for tractors and other outsize vehicles electric wire insulation encapsulating compounds steam hose and other mechanical rubber goods pond and reservoir sealant. Latex is used for paper coating, textile and leather finishing, adhesive formulations, air bags, tire vulcanization, self-curing cements, pressure-sensitive adhesives, tire-cord dips, sealants. 

Ethylene-propylene rubber has relatively high resistance to heat. Standard formulations can be used continuously at temperatures of 250-300°F (121-148°C) in air. hr the absence of air, such as in a steam hose lining or cable insulation covered with an outer jacket, higher temperatures can be tolerated. It is also possible by special compounding to produce material that can be used in services up to 350°F (176°C). Standard compoimds can be used in intermittent service at 350°F (176°C). 

The tire industry is probably the most important consumer of halobutyl rubbers for inner liners, tubes, tire sidewall compounds, and tire curing members. Other applications include heat resistant conveyor belts, steam hoses, gaskets, pharmaceutical stoppers, chemically resistant tank linings, adhesives, and sealants. 

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. 

EPDM rubber preferred for a great number of specific applications. For many years peroxide-cured EPDM based compounds have been applied, e.g., for window seals, automotive hoses, steam hoses, conveyer belts, roof sheeting, tank lining, roll coverings, mouldings, and last but not least, for electrical insulation and jacketing compounds. Two formulation types (403) are illustrated in Tables 33 and 34. 

Chlorinated polyethylene (CM) is produced by the chlorination of high density polyethylene either in solvent solution or aqueous suspension. The substituent chlorine on the saturated olefin backbone enhances heat and oil resistance. The chlorine also provides flame resistance. The polymer is thermoplastic when processed on conventional elastomer equipment, and compounds can be molded, calendered or extruded. Chlorinated polyethylene is most often steam cured using a peroxide curing system. The major end use is wire and cable applications, particularly flexible cords for up to 600 volts. Other major uses are in automotive hose, sheet goods and as an impact modifier in plastics. 

Halobutyl rubbers cannot be compounded to give the extraordinary level of moisture resistance that may be achieved with butyl vulcanisates because some of their vulcanisation by-products are water-soluble salts. For this reason they are not used in high-voltage electrical insulation but they possess sufficient moisture resistance to give outstanding performance in hose tubes and covers for hot water and superheated steam. 

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