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Temperature: -20℃ ~ 80℃ (standard); high temperature: 120/180/250℃ Protection: IP65/IP67 (dust / water wash) Explosion-proof: Exd II CT6 / Exia (chemical industry / lithium batteries) Voltage: DC 24V (preferred) / AC 220V / AC 110V Coil: continuous operation (Class H insulation) / intermittent
Two-position, two-way: Normally Closed (NC) / Normally Open (NO) Two-position, three-way: Pneumatically actuated (single‑acting cylinder) Two-position, five-way: Double‑acting cylinder (most common) Three-position, five-way: Center‑closed / Center‑vented / Center‑pressurized (requires pressure maintenance / mid‑stroke stop) Control type: Single‑coil (spring‑return) / Double‑coil (self‑holding)
Cylinder bore / stroke / speed → Calculate air consumption Q (L/min) Select based on Kv/Cv values (allow 20–50% margin) For pneumatic applications: Cv ≈ Q ÷ 1000 (Q: L/min) Port sizes (G1/8, G1/4, G3/8, G1/2, etc.) ≠ nominal diameter
Working pressure: minimum / normal / maximum (e.g., 0.2–0.7 MPa) Starting differential pressure: zero differential pressure (0 MPa) or ≥0.05 MPa Vacuum: -0.02 ~ -0.1 MPa High pressure: ≥1.0 MPa
Media (most critical; determines material and sealing) Compressed air / Vacuum / Nitrogen / Argon Water / Hot water / Steam (temperature?) Acids, alkalis, salt spray / Corrosive liquids (pH? composition?) Oil‑containing, dust‑containing, particulate‑laden, or slurry‑containing fluids
Direct‑acting (most commonly used for non‑standard applications; can operate with zero pressure differential) Pressure: 0–1.0 MPa; capable of starting with zero pressure differential Flow rate: Small to medium (DN1–DN15) Advantages: Simple structure, resistant to contamination, low‑temperature tolerance, fast response (10–30 ms) Disadvantages: High power consumption at large flow rates Applications: Vacuum systems, low‑pressure environments, frequent actuation, dusty conditions, and small non‑standard cylinders Pilot‑operated (standard, widely used; cost‑effective with high flow) Pressure: ≥0.05 MPa; requires a pressure differential Flow rate: Medium to large (DN15–DN50) Advantages: Energy‑efficient, high flow capacity, compact size Disadvantages: Cannot operate with zero pressure differential, sensitive to contamination, slower response (50–200 ms) Applications: Conventional pneumatic systems, large cylinders, stable air supply Step‑by‑step direct‑acting (non‑standard, suitable for hi
Valve Body Material 304 Stainless Steel: Humid environments, mild corrosion, general food‑grade applications 316 Stainless Steel: Salt spray, acids and alkalis, coastal areas, cleaning lines 316L Stainless Steel: Medical‑grade, sterile, CIP/SIP, pharmaceutical, high‑purity Brass: Dry air, non‑corrosive (cost‑effective) Cast Steel: High pressure, non‑corrosive Seal Material (determined by the medium and temperature) NBR (Nitrile): Air, oil, water; –30 to 80°C (standard) EPDM (Ethylene Propylene Diene Monomer): Hot water, steam, mild acids and alkalis; –40 to 120°C FKM/Viton (Fluorocarbon): Strong acids, strong alkalis, solvents, high temperatures; –20 to 180°C PTFE (Polytetrafluoroethylene): Strong acids and alkalis, high purity, sterile, up to 250°C (preferred for food and pharmaceutical industries) Metal Seals: High‑temperature steam, high pressure, zero leakage For use with stainless steel pneumatic cylinders (316/316L): Valve body made of 316L with FKM/PTFE seals. For use with stain
Two-position five-way (double-acting cylinder) 2V025-08: 2-way port, 304 stainless steel, direct-acting 3V210-08: 3-way, 316 stainless steel, pilot-operated 4V210-08-316L: 4V series, 316L stainless steel, food-grade MVSC-220-316: Gold-plated version, 316 stainless steel, non-standard Two-position three-way (single-acting cylinder) 3V110-06: 1-way, 304 stainless steel 3V210-08-NC: Normally closed, 316 stainless steel Stainless steel / Hygienic grade (compatible with stainless steel cylinders) SS-2V/3V/4V-316L: All-stainless steel, suitable for food and pharmaceutical applications Hygienic clamp-type solenoid valves: DN15–DN50, 316L stainless steel, PTFE seals
Ningbo Dongchao Automation Control (Highly recommended, compatible with stainless steel pneumatic cylinders) Key features: 316L sanitary grade, custom non‑standard designs, zero pressure differential, high‑temperature resistance, explosion‑proof Seals: PTFE/FKM, food‑grade Applications: pharmaceuticals, aseptic food processing, chemical industry, lithium‑ion batteries, and complete systems paired with stainless steel pneumatic cylinders.
Ningbo Dongchao Automatic Control (Strong Recommendation: Non‑Standard / 316L) Key Features: 316L medical‑grade material, non‑standard customization, extra‑long stroke, special interfaces Sealing: PARKER food‑grade, resistant to acids, alkalis, and high temperatures Applications: Pharmaceutical, sterile food processing, chemical industries, and lithium‑battery specialized cylinders Advantages: Strong technical expertise, rapid customization, convenient local after‑sales service in Ningbo