D643H Triple Eccentric Hard Seal Butterfly Valve

The electric regulating butterfly valve is a type within the categories of electric valves and electric regulating valves. The main connection methods include: flanged and wafer types. It is an important actuation unit in the field of industrial automation control. Two major analyses of the installation points for electric regulating butterfly valves: the installation position, height, and direction of inlet and outlet must comply with design requirements; note that the direction of medium flow should be consistent with the arrow direction marked on the valve body, and connections should be firm and tight. Before installation, the electric regulating butterfly valve must undergo an appearance inspection; the valve's nameplate should comply with the current national standard "General Valve Marking" GB12220. For valves with a working pressure greater than 1.0 MPa and those that serve as shut-off valves on main pipelines, strength and tightness performance tests should be conducted before installation. They can only be used after passing the tests. During the strength test, the test pressure should be 1.5 times the nominal pressure, with a duration of not less than 5 minutes; the valve body and packing should show no leakage to be considered qualified. Electric regulating butterfly valves can be classified by structural form into offset disc, vertical disc, inclined disc, and lever types. By sealing form, they can be divided into soft sealing and hard sealing types. Soft sealing types generally use rubber ring seals, while hard sealing types typically use metal ring seals.

Selection Rules

Stem diameter: For multi-turn rising stem valves, they cannot be assembled into electric valves. Therefore, if the maximum stem diameter allowed by the electric butterfly valve device cannot pass through the stem of the matched valve, the inner diameter of the hollow output shaft of the electric device must be larger than the outer diameter of the rising stem valve's stem. For partial-turn valves and non-rising stem valves among multi-turn valves, although the stem diameter passage issue does not need to be considered, the stem diameter and keyway dimensions should still be fully considered during selection to ensure normal operation after assembly.

Operating torque: Operating torque is the main parameter for selecting an electric valve device. The movement process of the electric butterfly valve can be controlled by the stroke, torque, or the magnitude of axial thrust. Since the operating characteristics and utilization rate of the electric valve device depend on the type of valve, the operating specifications of the device, and the position of the valve in the pipeline or equipment, the electric butterfly valve device is an indispensable equipment for achieving valve program control, automatic control, and remote control. Therefore, correctly selecting the electric valve device is crucial to prevent overload conditions (operating torque higher than the control torque). Typically, the basis for correctly selecting an electric butterfly valve device is:

The output torque of the electric device should be 1.2-1.5 times the maximum operating torque of the valve.

Electric butterfly valve operating thrust: There are two main structures of the electric valve device: one is without a thrust disc, where the output torque is directly output; the other is with a thrust disc, where the output torque is converted into output thrust through the stem nut in the thrust disc.

Number of output shaft rotations: The number of rotations of the output shaft of the electric valve device is related to the nominal diameter of the valve, the stem pitch, and the number of thread starts. H is the valve opening height, calculated as M = H / (S * Z) (where M is the total number of rotations the electric device should satisfy, S is the stem drive thread pitch, and Z is the number of stem thread starts). When placing an order, please specify:

I. 1. Product model 2. Nominal diameter DN, rated flow Kv 3. Signal pressure, spring range 4. Flow characteristics 5. Pre-valve and post-valve pressure 6. Medium type 7. Medium operating temperature range 8. Valve body and valve plug sleeve material 9. Whether with accessories, specify model 10. Any other special requirements

II. If the valve model of our company has been selected by the design unit, please order directly from our sales center based on the valve parameters.

III. When the application is very critical or the environment is complex, please provide design drawings and detailed parameters, and our engineering experts will carefully review and analyze them for you.