Manual Gear Operator (Gearbox)
Bevel or spur gear operator for manual operation of large-diameter ball, gate, butterfly, and plug valves.
Technical Specifications
| Type | Bevel Gear / Spur Gear |
| Torque Output | Up to 30,000 Nm |
| Body Materials | Ductile Iron, Cast Iron, Stainless Steel |
| Mounting Standard | ISO 5211 / Direct Mounting |
| Handwheel | Cast Iron or Aluminum (spokes or solid) |
| Protection Rating | IP65 / Weatherproof / Ex-proof option |
| Standards | ISO 5210,EN 15714-5 |
| Lead Time | Ex-stock Gujarat: Same day | Standard items: 2–4 weeks | Exotic alloys: 8–12 weeks |
Applications
Large gate valves, ball valves, butterfly valves, plug valves
About the Manual Gear Operator (Gearbox)
The manual gear operator (gearbox) provides mechanical advantage to enable a single operator to manually open or close large-bore or high-pressure valves that would otherwise require impractically high handwheel force. The worm gear or bevel gear mechanism multiplies the operator's handwheel torque by the gear ratio (typically 10:1 to 100:1) while proportionally reducing the output speed - a high gear ratio gearbox allows very high output torque but requires many handwheel turns to complete the valve stroke. Gear operators for quarter-turn valves (ball, butterfly, plug) typically use a bevel gear or worm gear that converts multiple handwheel rotations into the 90-degree valve stroke. Multi-turn gear operators for gate and globe valves stack gear stages to increase the torque multiplication for very large or high-pressure rising-stem valves.
The output flange of the gearbox is machined to ISO 5211 or ISO 5210 mounting standards, providing direct bolt-on compatibility with the valve top-works without additional adaptor plates. The handwheel is sized and rated for the maximum torque required at the operator's hand rim - typically designed for a 350 N operator hand force at the handwheel rim. The gearbox housing is IP65 or IP67 sealed for outdoor and weather-exposed installations. Vajra Industrial Solutions supplies bevel gear and worm gear operators for quarter-turn and multi-turn duty in torque ranges to 30,000 Nm to ISO 5210 and ISO 5211.
Where It's Used
Key industries and applications for the Manual Gear Operator (Gearbox)
Large pipeline ball valves
bevel gear operators on 8"–36" Class 150–600 trunnion ball valves at block valve stations; gear ratio selected so one operator can apply 350 N at the handwheel rim to overcome valve break-out torque at maximum differential pressure
Gate valve isolation
multi-turn worm gear operators on large gate valves (12"–36") in water transmission mains, pipeline isolation, and refinery plant - gear operator replaces the long rising stem with a compact flat-top operator accessible from grade or platform
Butterfly valve isolation
bevel gear operators on 12"–48" butterfly valves in water treatment, cooling water, and industrial process lines; chain wheel extension allows operation from ground level when valve is elevated in pipe rack or bridge
Underground and valve pit installations
compact gear operators with extended top works or with chain wheels for operation of valves in underground pits, valve vaults, and deep trenches without operator entry
Gate and sluice valve control on water authority
gear operators with position indicators (turns counter or position dial) on 16"–48" sluice gate valves and screw-spindle gate valves on reservoir, dam, and water treatment inlet/outlet
How to Choose the Right Manual Gear Operator (Gearbox)
Select gear ratio based on break-out torque at maximum differential pressure with a 1.5× safety factor, targeting maximum 350 N operator hand force at the handwheel rim. Higher gear ratios reduce required hand force but increase the number of handwheel turns for full stroke - verify the number of turns is acceptable (typically 10–80 turns for quarter-turn valves, up to several hundred for multi-turn gate valves). Specify IP65 or IP67 sealed housing for outdoor or exposed service. For elevated valve installations, add a chain wheel operator or extension spindle to allow operation from grade level.
Popular Configurations
Most commonly ordered specifications for the Manual Gear Operator (Gearbox)
Frequently Asked Questions
About Manual Gear Operator (Gearbox) - ordering, specs, delivery & compliance
What standards does the Manual Gear Operator (Gearbox) comply with?+
Our Manual Gear Operator (Gearbox) complies with ISO 5210, EN 15714-5. All products are manufactured to international standards and come with full material test reports (MTR), dimensional inspection reports, and hydrostatic test certificates on request.
What materials are available for the Manual Gear Operator (Gearbox)?+
The Manual Gear Operator (Gearbox) is available in Ductile Iron, Cast Iron, Stainless Steel. Material selection depends on your process fluid, temperature, pressure, and corrosion requirements.
What is the delivery lead time for Manual Gear Operator (Gearbox)?+
Standard stock sizes are available for immediate dispatch from our Vadodara warehouse. Custom sizes and special materials typically have a lead time of 2–6 weeks depending on specifications. We serve customers across India within 1–7 business days and export to the Middle East, Southeast Asia, Europe, and the Americas with full export documentation.
Can I get a custom Manual Gear Operator (Gearbox) for a specific application?+
Yes. Vajra Industrial Solutions supplies custom-engineered accessories for specific process conditions. Submit your technical requirements - including pressure class, temperature range, fluid type, end connections, and any special trim or coating needs - via our RFQ form or WhatsApp, and our engineering team will respond within 24 hours.
What pressure ratings are available for the Manual Gear Operator (Gearbox)?+
The Manual Gear Operator (Gearbox) is available in pressure ratings of PN10 to PN400 (ANSI Class 150 to Class 2500). Higher-pressure classes are available for critical service applications in oil & gas, power generation, and chemical processing.
How do I request a quote for the Manual Gear Operator (Gearbox)?+
You can request a quote by clicking the "Request Quote" button on this page, filling out our RFQ form at vajravyuh.com/rfq, emailing us at sales@vajravyuh.com, or WhatsApping us directly at +91-9979774557. Please include quantity, size, pressure class, material grade, and end-connection type for the fastest response.
Need a Quote for Manual Gear Operator (Gearbox)?
Our technical sales team responds within 24 hours. Share your specs and get competitive pricing.
Other Accessories
Limit Switch Box
Visual and electrical position feedback for automated valves.
View Details →
Solenoid Valve
Pilot solenoid valves for pneumatic actuator control.
View Details →
Valve Positioner
Pneumatic or electro-pneumatic positioner for precise valve positioning.
View Details →
Handwheel Override for Actuators
Declutchable manual override handwheel for pneumatic and electric actuators - allows manual operation during power/air failure.
View Details →