Why do regulating valves need to account for both low load and peak flow simultaneously? The cost of excessive capacity

Capacity selection should cover minimum, normal, and peak traffic. Only meeting the maximum traffic may cause daily operations to be concentrated at a very small opening; Providing each load point along with the corresponding pressure difference is more reliable than blindly increasing the diameter.

Each flow point needs to be equipped with its own pressure differential

The minimum, normal, and peak flow rates often correspond to different pump states, upstream supply pressure, and pipe network resistance. Combining the maximum flow rate with the maximum pressure difference of another state may result in an unrealistic capacity requirement. The operating condition table should list the flow rate, upstream and downstream pressure, temperature, and medium properties according to grouped data. Steam or gas should also indicate the state, and cannot be represented by a single volume flow rate to represent all loads.

Excessive capacity may narrow the effective control range

If the valve can meet most loads with a smaller opening, daily operation may be concentrated near the closed section. Mechanical friction, actual travel changes, and flow curves will have a more significant impact on the process. Meeting the maximum capacity does not prove that the minimum flow can be stably controlled; Different valve seats or valve internals may also be selected for the same DN. The flow capacity and pipeline connection diameter cannot be mixed into one choice.

Adjustable ratio is a capability description under specified conditions

The adjustable ratio of a product usually has defined and tested conditions, and the practical range after installation is also affected by the pipeline network, pressure difference, measurement, and actuator. The ratio in the promotion cannot be directly used as the minimum flow guarantee for any state of the factory. When the demand spans a large range, different capacity configurations or designed combination solutions can be evaluated. The combination scheme also needs to verify traffic allocation, switching logic, and control objectives, and cannot be determined solely by an adjustable ratio value.

Put the normal working point in the technical comparison

Procurement inquiries should first organize the normal production operation time and range, and then list the extreme peak values and duration. For the single seat adjustment structure of ZJHP, it is necessary to compare the closing load, valve internals, and actuators. The plan should specify the expected working range for each operating condition, as well as restrictions related to liquid vaporization or high-speed gas. The margin needs to consider real uncertainty, but it should not be stacked layer by layer to significantly deviate the capacity from daily load.

Comparison of selection information

Corresponding products and selection entrance

A good selection of regulating valves should not only allow peak values to pass, but also explain how they work under common, low load, and extreme conditions. Handing over grouped data of each point to the selection personnel can reduce the tendency to compensate for insufficient information with a large caliber.

Related structures can be combinedPneumatic single seat regulating valve ZJHP-16CUnderstanding of specific product information. See more similar directionsRegulating Valve Product Column。