YZ Series Manual Quarter-turn Worm Valve Gearbox
YZ Worm Gear Operator
The YZ series is YOYAGE's dedicated quarter-turn manual worm gearbox, purpose-built for the 90° operation of butterfly, ball, plug and rotary ball valves. It is the base model of the YZ family: combining it with the YZ-ZC spur gearbox creates the YZ-S for higher torque and ratio, and replacing the handwheel input with an actuator flange creates the YZ-D for electric operation. Eleven sizes deliver 500–6,825 Nm, with output torque matched to the ISO 5211 flange ratings and stem bore and mounting height following international standards. The precisely cast housing pairs a novel, attractive look with multiple material options, while the self-locking worm gear pair and tapered roller bearings keep operation flexible and efficient. ISO 5211 mounting flange; IP67 as standard, IP68 optional for special environments. Manufactured in compliance with CE and ISO 9001 standards.
- Standard Type
- Quarter-turn
- Gear Type
- Worm Gear
- Ratio
- 34:1–67:1
- Torque
- 500–6,825 Nm
- Protection
- IP67 (IP68 optional)
- Housing Material
- Ductile Iron, WCB (common)
Product Features
- Self-locking worm gear set prevents valve back-driving
- Heat-treated worm with high hardness and wear resistance
- Precision-ground gears for smooth rotation and high efficiency
- High-strength input shaft with protective plating
- C3/C5 coating system for surface protection
- Reliable bearing support for stable operation
- Grease-filled lubrication for extended service life
- NBR seals for enhanced sealing performance
- Rigorous torque and low-temperature testing
Custom Solutions
- Housing materials: Ductile iron, WCB, CF8/CF8M, LCC, LCB, LC1
- Full-bronze or bronze-rimmed worm wheel
- Gear ratio customization on request
- Handwheel & chainwheel size customization
- Worm gear hubs customization (Valve stem)
- MSS flange standard or custom connections
- Handwheel locking device
- Low-temperature service down to -59°C
- C5 coating system
- IP68 protection option
Technical Parameters & Dimensions
Read our selection guide: How to Choose a Valve Gearbox for Industrial Valve Applications
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Technical Parameters & Connection Size
| Model | Ratio | Max TorqueN·m | Max Torquekgf·m | Input TorqueN·m | FlangeISO 5211 | Flange Dia.D | Bolt Circle Dia.PCD D0 | Bolt SpecN-H-DP | ConvexD1×h | Max Stem Dia.Φd | Keyway |
|---|---|---|---|---|---|---|---|---|---|---|---|
| YZ-0 | 34:1 | 500 | 51 | 50 | F10 | 125 | 102 | 4-M10-15 | 70×3 | 30 | 8×7 |
| YZ-1 | 44:1 | 1,000 | 102 | 90 | F12 | 150 | 125 | 4-M12-18 | 85×3 | 42 | 12×8 |
| YZ-2 | 44:1 | 1,500 | 153 | 115 | F14 | 175 | 140 | 4-M16-20 | 100×4 | 50 | 14×9 |
| YZ-2J | 50:1 | 2,500 | 255 | 166 | F16 | 210 | 165 | 4-M20-30 | 130×5 | 60 | 18×11 |
| YZ-3 | 50:1 | 3,200 | 327 | 215 | F16 | 210 | 165 | 4-M20-30 | 130×5 | 60 | 18×11 |
| YZ-3J | 53:1 | 4,500 | 459 | 300 | F16/F20 | 250 | 205 | 8-M16-24 | 140×5 | 75 | 25×14 |
| YZ-4 | 55:1 | 4,950 | 505 | 300 | F25 | 300 | 254 | 8-M16-24 | 200×5 | 90 | 22×14 |
| YZ-4J | 67:1 | 5,200 | 530 | 258 | F30 | 350 | 298 | 8-M20-30 | 230×5 | 110 | 28×16 |
| YZ-5 | 62:1 | 5,580 | 569 | 300 | F30 | 350 | 298 | 8-M20-30 | 230×5 | 110 | 28×16 |
| YZ-5J | 67:1 | 6,030 | 615 | 300 | F35 | 415 | 356 | 8-M30-45 | 260×5 | 120 | 32×18 |
| YZ-6 | 65:1 | 6,825 | 696 | 350 | F35 | 415 | 356 | 8-M30-40 | 260×5 | 120 | 32×18 |
Appearance Size (mm)
| Model | A | B | C | L | L1 | L2 | H | H1 | ΦM |
|---|---|---|---|---|---|---|---|---|---|
| YZ-0 | 125 | 156 | 90 | 80 | 120 | 210 | 100 | 70 | 250 |
| YZ-1 | 150 | 185 | 110 | 85 | 133 | 223 | 105 | 68 | 350 |
| YZ-2 | 175 | 207 | 120 | 95 | 155 | 245 | 114 | 78 | 400 |
| YZ-2J | 210 | 245 | 140 | 115 | 189 | 279 | 132 | 93 | 450 |
| YZ-3 | 225 | 265 | 125 | 122 | 205 | 305 | 154 | 106 | 500 |
| YZ-3J | 300 | 331 | 186 | 147 | 240 | 340 | 155 | 105 | 600 |
| YZ-4 | 340 | 393 | 222 | 167 | 242.5 | 342.5 | 185 | 127 | 600 |
| YZ-4J | 350 | 418 | 243 | 185 | 270 | 470 | 185 | 122 | 650 |
| YZ-5 | 390 | 427 | 232 | 187 | 287 | 487 | 190 | 120 | 750 |
| YZ-5J | 430 | 488 | 275 | 225 | 325 | 525 | 195 | 132 | 800 |
| YZ-6 | 470 | 532 | 298 | 232 | 332 | 532 | 200 | 127 | 900 |
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