Angle adjustment of the structure and the use of the pneumatic valve

in the production process automation control system, adjust the pneumatic valve is an important and indispensable link, known as 'hands' of the production process automation, is one of the automatic control system of terminal control components. It is consists of two parts, actuators and pneumatic valve. From the point of view of hydraulic, regulate the pneumatic valve is a throttling element local resistance to change, adjust the pneumatic valve is according to the input signal by changing the schedule to change the resistance coefficient, so as to achieve the purpose of flow adjustment.
, Angle adjusting the structure of the pneumatic valve, pneumatic valve Angle adjustment in addition to the pneumatic valve body Angle for, other structures and single-seat pneumatic valve, its characteristics to determine the flow of a simple, small resistance, especially for high pressure drop, high viscosity, containing suspended solids and granular material flow regulation. It can avoid coking, bonding and jam phenomenon, also facilitate cleaning and self-purification.
use pneumatic valve, Angle adjustment the note:
( ） Positive and reverse use comparison: in general, pneumatic valve Angle adjustment adopts positive installation, namely the bottom into the side out. Occasions only in high-pressure differential and high viscosity, easy to coking, under the condition of suspended particulate medium, to recommend a reverse installation, namely material side in bottom out. Angle is the purpose of regulating pneumatic valve reverse in order to improve the unbalanced force and reduce the wear and tear of pneumatic valve core, as well as to high viscosity, easy to coking and suspended particulate medium flow, avoid coking and clogging.
（ ） Angle regulating pneumatic valve reverse analysis: jilin chemical industry co. , LTD. , acetaldehyde unit imported from west Germany, pv - Pneumatic valve Angle adjustment under the condition of high technology, recommend use reverse. The linkage in the water, with a strong oscillation Angle adjustment pneumatic valve, and a cacophony of noise and commissioning h pneumatic valve core is broken. When foreign experts believe is caused by the pneumatic valve core manufacturing quality is bad. The author thinks that is not quality problem, but due to the use of unreasonable. Here are the fracture reason is analyzed. As we know, now in addition to the control of pneumatic valve and pneumatic diaphragm valve completely symmetrical in structure, the adjustment of the structure of all other pneumatic valve is not symmetrical. When regulating pneumatic valve to change flow direction, due to the change of flow will cause) Value changes. Each kind of regulating the normal flow of pneumatic valve to make the direction of the pneumatic valve core to open ( Positive use) , the factory also provide only normal flow when the flow capacity) Value and the flow characteristic. When regulating pneumatic valve reverse use, both fluid along to close the pneumatic valve core in the direction of the flow, to adjust the flow capacity of pneumatic valve will increase. Water linkage, the simulated process conditions can't reach normal soon, to adjust for a long time in a small open of the pneumatic valve state, due to the effect of unbalanced force, there will be a serious instability. So regulating pneumatic valve will produce strong screeched shock and noise, and pneumatic valve core fracture soon. And under the condition of normal process, adjust the opening of pneumatic valve is modest, even if small open degree is short, so regulating pneumatic valve can be used normal safety. Rotor pump
( ） Pneumatic valve flow Angle adjustment is simple, small resistance, generally applies to positive use ( Installation) 。 In high pressure drop, however, recommend Angle adjustment reverse use pneumatic valve, to improve the unbalanced force and reduce the damage for pneumatic valve core, as well as to the flow of the medium, avoid regulating pneumatic valve coking and clogging. Angle adjusting is pneumatic valve used in reverse, especially should avoid long time open the small open degree, in case of strong oscillation pneumatic valve core damage. Trial production stage, especially in petrochemical plants due to the low load trial production, design, process conditions can't meet the requirements, soon reverse use pneumatic valve Angle adjustment should as far as possible to avoid a long time in the small open open situation, in case the Angle adjustment pneumatic valve damage. In general, Angle regulating pneumatic valves are not recommended for reverse use, only in high pressure, high viscosity, easy to coking and medium containing suspended particles are recommended reverse to use. Reverse when using, should avoid long-term running small open degree, especially more attention should be paid to during commissioning.