Manual
YZ Worm Valve Gearbox
- Standard Type
- Part-turn (quarter-turn)
- Gear Type
- Worm
- Ratio
- 34:1 – 67:1
- Torque
- 500–6,825 Nm
Part-turn Valve Gearboxes & Quarter-Turn Gear Operators
YOYAGE part-turn gearboxes turn the valve stem through 90° for butterfly, ball and plug valves, with worm-gear series covering 240 to 850,000 Nm in manual, electric and pneumatic declutchable versions.
Confirm Structure & Material
Valve type decides part-turn vs multi-turn and worm / bevel / spur gearing; service conditions decide the housing material.
Confirm Drive Type
Manual handwheel, electric actuator (D-suffix series), or pneumatic declutchable operation.
Determine the Model
Match torque and ratio to the valve, then verify the mounting flange and stem dimensions.
Send Inquiry
Send valve type, size, torque and stem data for a quotation, selection support or custom design.
Product Range
Find the Right Part-turn Valve Gearbox Series
Standard Type
Applicable Valve Type
Gear Type
Operation Type
Manual
YZ-S Worm Valve Gearbox
- Standard Type
- Part-turn (quarter-turn)
- Gear Type
- Worm
- Ratio
- 78:1 – 19320:1
- Torque
- 1,300–850,000 Nm
Electric
YZ-D Worm Valve Gearbox
- Standard Type
- Part-turn (quarter-turn)
- Gear Type
- Worm
- Ratio
- 34:1 – 82:1
- Torque
- 500–250,000 Nm
Electric
YZ-SD Worm Valve Gearbox
- Standard Type
- Part-turn (quarter-turn)
- Gear Type
- Worm
- Ratio
- 51:1 – 8860:1
- Torque
- 500–850,000 Nm
Manual
Ductile Iron Only
HX Worm Valve Gearbox
- Standard Type
- Part-turn (quarter-turn)
- Gear Type
- Worm
- Ratio
- 36:1 – 4170:1
- Torque
- 670–220,000 Nm
Manual
Ductile Iron Only
HXH Worm Valve Gearbox
- Standard Type
- Part-turn (quarter-turn)
- Gear Type
- Worm
- Ratio
- 29:1 – 2895:1
- Torque
- 260–120,000 Nm
Manual
MY Worm Valve Gearbox
- Standard Type
- Part-turn / Multi-turn
- Gear Type
- Worm
- Ratio
- 24:1 – 68:1
- Torque
- 300–8,500 Nm
Manual
MY-1S Worm Valve Gearbox
- Standard Type
- Part-turn / Multi-turn
- Gear Type
- Worm
- Ratio
- 72:1 – 5280:1
- Torque
- 1,000–170,000 Nm
Electric
MY-D Worm Valve Gearbox
- Standard Type
- Part-turn / Multi-turn
- Gear Type
- Worm
- Ratio
- 33:1 – 80:1
- Torque
- 800–150,000 Nm
Electric
MY-1SD Worm Valve Gearbox
- Standard Type
- Part-turn / Multi-turn
- Gear Type
- Worm
- Ratio
- 50:1 – 1248:1
- Torque
- 300–150,000 Nm
Manual / Pneumatic Declutchable
SD Worm Valve Gearbox
- Standard Type
- Part-turn (quarter-turn)
- Gear Type
- Worm
- Ratio
- 26:1 – 98:1
- Torque
- 240–3,800 Nm
Manual / Pneumatic Declutchable
MY-F Worm Valve Gearbox
- Standard Type
- Part-turn (quarter-turn)
- Gear Type
- Worm
- Ratio
- 26:1 – 420:1
- Torque
- 390–16,000 Nm
No standard part-turn series matches your filters.
YOYAGE can design and build part-turn gearboxes beyond the standard range. Send us your valve size and torque requirement.
Product Knowledge
Part-turn Valve Gearbox Structure, Materials & Applications
A quick reference to the structure, worm gear train, materials and service options behind the YOYAGE part-turn range.
Part-turn Valve Gearbox Structure and 90° Travel
A part-turn valve gearbox rotates the valve stem through 90° to open or close the valve, with mechanical stops that define the fully open and fully closed positions. It is the correct structure for butterfly, ball and plug valves, where the disc or ball turns a quarter turn.
The valve type decides the structure before any other decision: quarter-turn valves need a gearbox with defined 90° stops, and the required output torque then sets the series size. YOYAGE part-turn gearboxes cover 240 to 850,000 Nm across 12 worm-gear series.
Worm Gearboxes: Self-Locking Quarter-Turn Drive
All YOYAGE part-turn series use a worm gear train. The worm and wheel multiply handwheel or actuator input into valve torque and hold the valve position when the input is released, which suits quarter-turn valves that must stay open or closed.
Part-turn ratios run from 24:1 to 19320:1. Manual series use a handwheel; the D suffix denotes electric actuator input; pneumatic declutchable series allow manual operation with an actuator mounted.
Housing Materials, Coating and IP Protection
Housing material follows the service environment: ductile iron for general industrial duty, WCB cast steel for higher pressure and temperature, CF8/CF8M stainless steel for corrosive media, and LCC/LCB/LC1 low-temperature cast steel for cold service.
Protection is IP67 as standard, with IP68 available for buried or frequently flooded installations. C3 and C5 coating systems are available for outdoor, coastal and corrosive sites.
Applications, Customization and Quality Control
YOYAGE part-turn valve gearboxes and gear operators are used in water management, oil and gas, power generation and chemical processing, where reliable quarter-turn valve operation is required. The 12 standard part-turn series cover 240 to 850,000 Nm in manual, electric and pneumatic declutchable versions.
Beyond the standard range, gear ratios, handwheel and chainwheel sizes, stem bores, flange standards and materials can be adapted to the valve, and every custom design is confirmed by drawings before production. Products are torque-tested and low-temperature tested in an ISO 9001-certified plant; all products carry the CE mark.
FAQ
Part-turn Valve Gearbox Questions & Answers
Selection, torque, materials, customization and quotation questions we are asked most often about part-turn gearboxes.
Butterfly, ball and plug valves, which open and close with a 90° stem rotation. A part-turn gearbox provides the defined open and close stops these valves need, so the valve type always decides the structure first.
The 12 standard part-turn series cover 240 to 850,000 Nm with ratios from 24:1 to 19320:1. Manual, electric actuator input (D suffix) and pneumatic declutchable versions are available; select the series whose maximum torque is above the valve's required torque including the safety factor.
Confirm the valve's required output torque including the safety factor, then select the series whose maximum torque is above that value and closest to it. The ratio follows the allowed manual input effort or the electric actuator's input torque. Finally check the mounting flange and stem dimensions against the valve.
Standard housings are ductile iron, with WCB cast steel, CF8/CF8M stainless steel and LCC/LCB/LC1 low-temperature steel available for other service conditions. Protection is IP67 as standard with IP68 optional, and C3 or C5 coating can be specified for outdoor and corrosive environments.
Yes. Gear ratios, handwheel and chainwheel sizes, stem bores, flange standards, housing materials and coating systems can be adapted, and every custom gearbox is confirmed by drawings before production starts. See Custom Solutions.
Send the valve type and size, required torque, stem dimensions, connection or flange standard, operation type (manual, electric or pneumatic declutchable) and quantity. If some data is missing, the YOYAGE team will review the application and recommend a suitable solution — Contact Us.
Need a Part-turn Valve Gearbox Solution?
Send your valve type, size, and torque requirements to the YOYAGE team for part-turn gearbox selection support and quotation.