The development of butterfly valve and its application in the process of easy to understand

In the 1930s, the United States invented the butterfly valve, which was introduced to Japan in the 1950s and was not commonly used in Japan until the 1960s. However, promotion in our country was after the 1970s. At present, butterfly valves of DN300 mm or above have gradually replaced gate valves in the world. Compared with the gate valve butterfly valve has a short opening and closing time for the moment of small, small installation space and light weight. Take DN1000 as an example, the butterfly valve is about 2T, while the gate valve is about 3.5T, and the butterfly valve is easy to combine with various driving devices, and has good durability and reliability. The disadvantage of the rubber-sealed butterfly valve is that when it is used for throttling, cavitation may occur due to improper use, causing the rubber seat to peel and damage. To this end, the international development of metal seal butterfly valve, cavitation area decreases in recent years, China has also developed a metal seal butterfly valve in Japan in recent years also developed cavitation-resistant, low vibration, low noise comb-shaped butterfly valve. General seal seat life under normal circumstances, rubber 15 years - 20 years, 80 years of metal - 90 years. But how to choose correctly according to working conditions. The relationship between the opening of the butterfly valve and the flow rate changes substantially linearly. If it is used to control the flow, its flow characteristics are closely related to the flow resistance of the pipe. For example, the diameters and forms of the valves installed in the two pipes are all the same, while the pipe loss coefficient is different, and the flow difference of the valve will also be very large. ? If the valve is in a state of large throttling, the back of the valve plate is prone to cavitation, the possibility of damage to the valve, are generally used outside the 15 °. When the butterfly valve is at the opening, the shape of the opening formed by the valve body and the front end of the butterfly plate is centered on the valve shaft, and the two sides form a different state. The front end of the butterfly plate on one side moves in the direction of flowing water while the direction of the counter flow Therefore, one side of the valve body and the valve plate is formed like a nozzle-shaped opening, the other side is similar to the orifice-shaped opening, the nozzle side is faster than the throttling side of the flow rate, and the throttling side valve generates a negative pressure below, Rubber seals tend to come off. Butterfly valve operating torque, due to the opening and the valve opening and closing direction of different values, horizontal butterfly valve, especially large-diameter valve, due to the depth of the valve shaft, the difference between the head and the resulting torque can not be ignored. In addition, the valve inlet side of the device elbow, the formation of bias current, the torque will increase. Valve in the middle of the opening, due to the role of water flow torque, the operating mechanism needs self-locking.

Spandex Warping Machine

Spandex Warping Machine

Spandex warping machine also called spandex yarn warping machine; elastic yarn warping machine.

A-ZEN spandex warping machine AZE318 with vertical creel is driven by 5 sets high performance servo motors and adopted with advanced precisive laser to measure distance so that spandex warping is more stable, well equipped with and easier to operate. It is suitable for warping all kinds of spandex, especially for requirement of knitting high quality elastic textiles.

Technical Data:

Warp Line Speed: 100-600m/min;

Beam Size: Φ21"*21";

Warping ends: According to customers` demand;

Pre-drafting: 0-200%; Final Draft: 15-100%;

Brake time less than 0.6 s, the deviation of stop synchronization is less than 3%;

Creel Capacity: 616, 700, 728, 784, 792, 896, etc.

Servo Motor Power: Warper head power 13.2KW, Warper Head Tension Roller 2.9KW, Draft Roller 4.6KW, Creel: 2*6.9KW;

Main Motor: 10KW AC frequency conversion control;

Control Mode: Computerized real-time control, and user-friendly operation interface.

Spandex Warping Machine,Elastic,Beam Warping Machine, Yarn, Computerized Split Yarn Warping Machine

CHANGZHOU A-ZEN TEXTILE TECHNOLOGY CO.,LTD , https://www.barmachinery.com