Can percent characteristic be selected for all control valves? Then what is the purpose of linear valves?
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Can percent characteristic be selected for all control valves? Then what is the purpose of linear valves? This question is quite basic; please don’t laugh at it. Generally, what is used to determine the flow characteristics of a control valve?
Linear valves are used in applications that do not require precise control
Generally, equal percentages come first, followed by a parabolic pattern, and then a linear one
Under other identical conditions, which is more expensive, equal-percentage valves or linear valves? How many times can the price differ? Which type of valve is easy to maintain, and which one is difficult to maintain with high maintenance costs?/
The selection of the flow characteristic for control valves is determined by the requirements of the process. For example, in the case of equal percentage characteristics, the relationship between relative stroke and relative flow is not linear; at each point along the stroke, the change in flow resulting from a unit change in stroke is proportional to the flow value at that point, with the percentage change in flow remaining constant. The relative stroke of the linear characteristic is in a straight-line relationship with the relative flow rate; the change in flow rate resulting from a unit change in stroke remains constant ； When the flow rate is high, the change in the relative value of the flow rate is small; when the flow rate is low, the change in the relative value of the flow rate is large.