How to prevent the chemical centrifugal pump pipeline regulating valve plugging and stuck?

How to prevent the chemical centrifugal pump pipeline regulating valve plugging and stuck?

Spring setting range: regulating valve actuator spring adjustment range, to balance the actual process force.
Flow capacity: Rated flow rate through the valve under specified conditions.
Gap flow: The flow rate that is lower than the smaller controllable flow rate when the closure element is not closed.
Diaphragm pressure range: The difference between high and low diaphragm pressure range.
This can be considered an inherent or installed feature.
Double acting actuator: An actuator that can provide power in either direction.
Dynamic unbalance force: Due to the action of process fluid pressure, at any specified opening, the effective area on the spool: in film actuators, the effective area is the area of the diaphragm that effectively produces the output force.
The effective area of the diaphragm may change as it moves, usually being larger at the beginning of the stroke and smaller at the end of the stroke.
Molded diaphragms have a smaller effective area change than flat diaphragms, so molded diaphragms are recommended.
Degassing – Off: A condition in which the valve stopper moves to the closed position when drive power is lost.
Degassing – Open: A condition in which the valve closure element moves to the open position when drive power is lost.
Degassing — safety: A characteristic of the valve and its actuator that, in the event of an interruption in the drive energy supply, causes the valve closure element to move to fully closed, fully open, or left in the previous position, either of which is considered necessary to protect the process.
Failure-safe modes of action may require auxiliary controls attached to the actuator.
Flow characteristics: The relationship between the flow rate through the valve and the percentage rated stroke as the percentage rated stroke changes from 0 to 100%.
The term should always be expressed as either an inherent flow characteristic or an installed flow characteristic.
Flow coefficient (Cv value) : A constant (Cv value) associated with the valve geometry for a given stroke that can be used as a measure of flow capacity.
It is the number of US gallons of 60¡ãF water flowing through the valve per minute at a pressure drop of pounds per square inch.
High pressure recovery valve: A valve structure that disperses relatively little fluid energy due to its streamlined internal profile and small fluid turbulence.
As a result, the pressure downstream of the valve retraction section returns to a high percentage of the inlet pressure.
Dc general valves, such as rotary ball valves are typical of high pressure recovery valves.
How to prevent chemical centrifugal pump pipeline regulating valve blocking and card?
Chemical centrifugal pump can transport the critical state of the liquid. Critical liquids tend to vaporize when the temperature rises or the pressure drops. In order to avoid the destruction of mechanical seals, packing seals and labyrinth seals due to dry friction due to the vaporization of liquid, this kind of chemical pump must have a structure that fully excludes the gas occurring in the pump. In the application of centrifugal pump installation, supporting facilities in the pipeline will generally install gate valve, regulating valve is a common flow regulation valve equipment, according to the application and conveyor liquid is not the same, regulating valve phase part will be blocked or stuck, so how to prevent the chemical centrifugal pump pipeline in the regulation valve block and stuck? The following content will give you a brief introduction, I hope to help you.
1. Install pipeline filter method
On the calibre of the regulating valve, especially in the very small flow regulator, the throttle valve gap is very small, there can be no slag in the medium. In case of blockage, install a filter device on the pipe in front of the valve to ensure smooth passage of the medium. For the regulating valve with the positioning instrument, the abnormal working of the positioning instrument and the blockage of the throttle valve port of the hydraulic valve block are common faults. Therefore, when working with the locator, it is necessary to solve the gas source. The general choice is to install the gas filter reducing valve on the gas source pipeline before the locator
2, media erosion method
Use the erosion kinetic energy of the medium itself, erosion and bring easily settled, easily blocked items, and then improve the anti-blocking effect of the valve. Common ways are: change to flow closed application; Use motion sensing oil circuit board; The throttle valve port is placed at the erosion interest. Special attention should be paid to improving the erosion resistance of the raw materials of the throttle valve.
3. External erosion method
For some easy to settle, with liquid particulate matter medium selection of general valve adjustment, often blocked at the throttle valve port, conductive place, can be under the valve cover plug external erosion of vapor and vapor. When the valve is blocked or stuck, open the external steam body or steam gate valve, can only be cleaned without moving the regulating valve condition, so that the valve all normal operation.
4, direct connection into angular method
The direct connection is inverted S fluidity, the flow path is complicated, the upper and lower cavity dead zone is many, for the settling of the medium shows the area. Angular connection, the medium like through the 90¡æ bend pipe, good erosion characteristics, small dead zone, easy to design the scheme into a flow. Therefore, the application of directly connected regulating valves can be changed to Angle valve application when causing slight obstruction.
5, expand the throttle gap method
Such as liquid particles in the media or corroded welding and rust in the pipeline caused by not on the throttle port blocking, stuck and other common faults, can be changed into the throttle valve parts with large gap for the total area of the throttle valve for window ventilation, mouth type valve center, sleeve specifications, with the total area of the throttle centralized rather than round, common faults can be very easy to be covered by plants. If it is a single, two-seat valve, the plunger pump valve center can be changed into a V-shaped port valve center, or changed to sleeve valve, etc.
6. Cleaning method
Welding, rust, slag in the pipeline in the throttle valve port, directional position, lower valve cover balance hole wall to block or jam, resulting in valve heart incline, directional surface contusions and scratches, stamping on the surface. This is often caused by new system software and maintenance after commissioning. It is a common failure in common use. In case of this situation, it is necessary to unload and clean up, remove slag, such as sudden surface damage should also be ground; Open the bottom plug together to wash away the slag falling into the lower valve cover from the equalization hole and clean the pipe. Before use, let the regulating valve open fully, the media fluidity after a period of time to include all normal operation.