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During construction, due to the long time asked casting, in Polyurethane foaming machine The mixing pressure must be constant during pouring. The pressure white balancing device is particularly important. The pressure balancing device is installed on the mixing head nozzle, which is composed of nozzle seat, moving spray needle, balance spring, spring seat, spring pretension device and air pressure adjusting piston. The movable spray needle can move back and forth in the nozzle seat to change the sectional area of the nozzle. The rear end of the movable spray needle is equipped with a spring seat and a balance spring. The spring preload can be adjusted by adjusting the spring pretension device and air pressure adjusting piston.

　 When the raw material enters the nozzle seat, the pressure will push the active spray needle to move backward and compress the spring, so as to reach the balance between the mixing pressure of the raw material and the spring pressure. The slight pressure change at the end of the material can be balanced by the spring pressure. In the production process, the spring pre-pressure can be adjusted by adjusting the pressure of compressed air in the air piston to reduce the spring balance pressure range, so as to ensure the mixing pressure and balance the pressure fluctuation in the pouring process of the polyurethane foam equipment.

　 Finally in the Polyurethane foaming machine The control system of the equipment is equipped with alarm parameters of flow, pressure and proportion. When each parameter of the equipment exceeds the error range, it will alarm in vain to ensure the safety of the equipment and the operator.