The difference between gate valve and globe valve in structure and principle

The difference between gate valve and globe valve in structure and principle

In view of the structural characteristics and medium characteristics of the polypropylene assembly loop reactor, the structural design of the safety valve of the loop reactor is very different from other common safety valves, as detailed in the following four aspects.

Inlet valve seat structure design

The polypropylene safety valve seat is completely different from the nozzle-shaped flow channel design of the common safety valve. In order to ensure the continuous flow of the medium material in the reaction process of the loop pipe, the shape of the butting surface is completely connected with the pipeline, and the inlet of the valve seat is designed to be connected with the pipeline. The arc size of the main pipeline of the equipment is the same as the arc size, so as to avoid the inflection point of the pipeline flow due to the change of the local structure of the safety valve, resulting in the dead zone of the flow channel which is easy to cause the medium to condense. When the medium flows through the inlet of the safety valve, it is easy to produce Coagulation, accumulation, or blockage of the safety valve inlet, affecting the normal operation of the safety valve and equipment.

Seal structure design

The sealing structure of the safety valve used in the polypropylene loop reactor adopts a soft-sealed split structure. The main reason is that the polypropylene particle medium is easily retained on the metal sealing surface, so that the sealing performance cannot be well guaranteed. Selecting a soft seal can effectively ensure the online sealing of the stainless steel valve and minimize the influence of the medium on the sealing of the stainless steel valve.

Soft seal split structure, the sealing structure is designed as a split threaded fastening structure, which is divided into three parts: valve disc, sealing ring and pressure block. The sealing ring is fixed in the groove formed by the detachable metal pressure block and the valve disc. In the groove, the overall wrapping design can effectively prevent the sealing ring from being blown out, and the replacement of the sealing ring can be completed relatively easily by removing the pressure block during inspection and maintenance.