1. Complete Working Process of Multi-Turn Electric Globe Valve
The electric globe valve relies on a multi-turn actuator to achieve automated fluid control. The entire operation consists of a three-step signal-logic sequence.
Phase 1 – Signal Reception: The actuator paired with the multi-turn electric globe valve can receive 4–20 mA analog signals or digital bus signals from PLC, DCS, or SCADA control systems. The current value output by the system corresponds to the specified valve opening, enabling remote precise positioning.
Phase 2 – Mechanical Transmission: An internal servo motor combined with a reduction gear train converts electrical energy into reciprocating linear mechanical motion, driving the valve stem to perform vertical multi-turn lifting movement. Unlike the 90° rotation of ball valves, the globe valve stem follows a purely linear stroke.
Phase 3 – Flow Regulation: The valve stem moves the disc vertically away from or toward the valve seat, changing the flow cross‑section of the medium. This linearly regulates the pipeline flow rate and pressure, enabling stable control of output volumes for steam, chemical liquids, and other media.
2. Five Key Selection Criteria
(1) Actuator Type: Distinguish between on‑off type and modulating electric globe valve.
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For simple on/off duty, choose the on‑off type.
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For continuous flow control in chemical or thermal applications, a modulating electric globe valve is mandatory, with positioning accuracy up to ±1%.
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In explosion‑proof plants, always specify an explosion proof electric globe valve to meet oil/gas and chemical safety standards.
(2) Valve Body Material – Match the Medium:
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For ordinary water and ambient‑temperature gases, cast iron bodies are acceptable.
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For corrosive chemicals, purified water, or high‑temperature steam, prefer 304/316 stainless steel electric globe valve.
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For high‑temperature and high‑pressure conditions, WCB carbon steel bodies may be chosen.
(3) Connection Type: flange electric globe valve is the mainstream choice for DN50 and above.
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Small diameters DN15–DN40 may use threaded connections.
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DN50 and industrial main pipelines should uniformly adopt flange electric globe valve.
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Welded types are suitable for ultra‑high‑pressure oil and gas pipelines.
(4) Pressure and Temperature Ratings:
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Check pressure class against ANSI and ASME standards.
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For steam media, the maximum applicable temperature is 450°C.
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For cryogenic conditions, select special low‑temperature sealing structures.
(5) Leakage Class: Soft‑sealing (zero leakage) is suitable for clean water; metal hard‑sealing is appropriate for high‑temperature media containing particulates.
3. Main Industrial Application Scenarios
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Thermal Power Plants: modulating electric globe valve for stable regulation of boiler steam supply flow.
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Chemical Industry: explosion proof electric globe valve for transporting flammable/explosive solvents and acid/alkali media.
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Water Treatment & Municipal: stainless steel electric globe valve for pure water and wastewater circulation pipelines.
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Food & Pharmaceutical: polished stainless steel bodies that meet hygienic production standards.
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Oil & Gas Extraction: high‑pressure flange electric globe valve for on/off and regulation of crude oil and natural gas transmission.
4. Brief Selection Pitfalls to Avoid
Many engineering purchasers confuse ball valves with globe valves. Ball valves are suitable for fast on/off but have poor regulation accuracy, whereas the electric globe valve offers linear flow characteristics that are far better suited for continuous process control.
When selecting, prioritise three core conditions: medium corrosiveness, on‑site explosion‑proof rating, and pipeline connection specifications – this will significantly reduce later leakage and sticking failures.
