Common faults and solutions of SAMSON valve positioners

SAMSON valve positioner working principle

(1) It is used for important adjustment systems with high requirements for adjustment quality to improve the positioning and reliability of the adjustment valve.

(2) It is used in the occasions where the pressure difference between the two ends of the valve is large (△p>1MPa). By increasing the air source pressure, the output force of the actuator is increased to overcome the unbalanced force generated by the liquid on the valve core and reduce the stroke error.

(3) When the medium to be adjusted is high temperature, high pressure, low temperature, toxic, flammable and explosive, in order to prevent external leakage, the packing is often pressed very tightly, so the friction between the valve stem and the packing is large. Time lag can be overcome with a locator.

(4) When the medium to be adjusted is a viscous fluid or contains suspended solids, the positioner can overcome the resistance of the medium to the movement of the valve stem.

(5) It is used for regulating valve with large diameter (Dg>100mm) to increase the output thrust of the actuator.

(6) When the distance between the regulator and the actuator is more than 60m, the positioner can overcome the transmission delay of the control signal and improve the response speed of the valve.

(7) It is used to improve the flow characteristics of the regulating valve.

(8) When one regulator controls two actuators to implement split-range control, two positioners can be used to accept low input signal and high input signal respectively, then one actuator acts at low range and the other moves at high altitude, which constitutes a split. program adjustment.

SAMSON AG, Germany, was founded in 1907 and its headquarter is located in Frankfurt, Germany. During more than 100 years of growth and development, SAMSON has always been committed to the research and development, production and sales of control valves and instrumentation. Its unique product development and innovation capabilities, stable and reliable product quality and perfect after-sales service have created great value for customers and won a good reputation for SAMSON. At present, SAMSON's products and network have covered the whole world, providing products and perfect solutions for global users. The SAMSON brand positioner is mostly used in the 4763 series in China. As an important accessory of the pneumatic control valve, the 4763 valve positioner accepts the electric or pneumatic control signal output by the control system or controller, and assists the adjustment of the pneumatic actuator according to the preset relationship. valve position and achieve accurate positioning. The valve positioner compares and processes the input control signal (given parameter W) and the control valve position feedback signal (adjusted parameter X), and then outputs the corresponding pneumatic control signal pst (output parameter Y) to the pneumatic actuator. The characteristics of SAMSON valve positioners are as follows:

Compact structure and low maintenance

Arbitrary assembly position

Not affected by mechanical vibration

Positive and negative effects can be adjusted

Good dynamic response characteristics

Adapt to conventional or split-range control

Adjustable ratio/gain

Adjustable output air volume

Low gas consumption

Special type can use oxygen gas source