In the traditional production process, the main raw materials of fire hoses are natural rubber and styrene-butadiene rubber. In recent years, tire tread rubber has begun to appear in common fire hose formulas. Recycled tread rubber is a variety of tire reclaimed rubber. It is processed from tire tread rubber powder. The effective rubber hydrocarbon content is higher than that of ordinary full tire reclaimed rubber. It has good elasticity and mechanical strength. It can be used for the inner and outer layers of fire hoses. Rubber preparation. Fire hoses have different requirements for different rubber layers, different amounts of tread recycled rubber, and different compounding agents are used.
1.Reference formula for outer layer of fire hose with tread rubber
70 parts of natural rubber, 30 parts of styrene-butadiene rubber, 50 parts of tread rubber, 6 parts of zinc oxide, 2.5 parts of stearic acid, 100 parts of light calcium, 35 parts of carbon black, 5 parts of heavy oil, 5 parts of coumarone, anti-aging 3 parts of agent, 1.5 parts of protective wax, 1.8 parts of accelerator, 2.2 parts of sulfur, total: 312 parts.
2. Coordination skills of the outer rubber vulcanization system of fire hoses with recycled tread rubber
When using natural rubber / styrene-butadiene rubber / recycled tread rubber and rubber compound to produce the outer layer of ordinary fire hoses, rubber product manufacturers choose sulfur vulcanization and can use the accelerator DM and accelerator M, with accelerator DM as the main accelerator. By adjusting the amount of accelerator M to adjust the vulcanization speed, the tensile strength and constant tensile stress of the outer layer of the fire hose are further improved.
3. Coordination skills of the outer rubber filling system of the fire hose with recycled tread rubber
When using recycled tread rubber to replace some of the original rubber to reduce the production cost of ordinary fire hoses, choosing a large amount of light calcium filling can further reduce the cost of raw materials; in order to improve the physical and mechanical strength of fire hoses, rubber product manufacturers can add an appropriate amount of carbon black 2LLYY0401. The combination of high wear-resistant carbon black and semi-reinforced carbon black can improve the mechanical strength of the outer rubber of fire hoses, reduce heat generation, and improve the aging resistance of outer rubber.
4. Coordination skills of the outer rubber anti-aging system of the fire hose with the recycled tread rubber
The outer rubber of ordinary fire hoses is directly exposed to the air during the application process. It has strict requirements on the aging resistance, heat resistance, and ozone resistance of rubber materials. Rubber product manufacturers can use antioxidants to directly delay the aging time of rubber materials. Extend hose life. The combination of antioxidant J and antioxidant DFC-34 can further improve the thermal oxygen aging, ozone aging and fatigue cracking performance of fire hoses.
When designing the formula for the outer layer of fire hoses containing recycled tread rubber, rubber product manufacturers also need to take into account the shrinkage and other indicators of the rubber, and adjust the formula appropriately to lay a good foundation for subsequent vulcanization, molding and other process operations.