How do I select a MY-F model by output torque and cylinder connection?

Select the model whose rated output torque meets the valve's required torque with an adequate safety factor (the Output Torque row lists the rating), then confirm the Cylinder Connection A0×A1 and the PDC(D2) flange match your pneumatic actuator, and the valve-side Bolt Circle PDC(D0) and bore d match the valve stem. See our selection guide for a step-by-step method.

Which valves can the MY-F series be mounted on?

Butterfly, ball and plug valves with 90° quarter-turn travel. The valve-side mounting flange follows ISO 5211, and the stem bore and mounting height comply with international standards, so the gearbox assembles directly onto the valve.

Can the MY-F gearbox be used outdoors or in submerged conditions?

Standard protection is IP65. For special environments such as flooding-prone or buried installations, IP68 and immersion protection are available on request.

MY-F Worm Valve Gearbox, 390–16,000 Nm

Name: MY-F Series Manual / Pneumatic Declutchable Quarter-turn Worm Valve Gearbox
Brand: YOYAGE

Manual / Pneumatic Declutchable YOYAGE MY-F manual / pneumatic declutchable worm valve gearbox for butterfly and ball valves

Product Overview

MY-F Worm Gear Operator

The MY-F series is a standalone quarter-turn worm gear operator that sits between a pneumatic actuator and the valve — unlike the MY and YZ manual families, it uses a declutchable structure that switches between manual handwheel and pneumatic actuator operation. In normal service the pneumatic actuator drives the valve through the worm gear stage; when the air supply fails or manual operation is needed, the operator disengages the pneumatic side and drives the valve by handwheel, so the gearbox can replace a pneumatic actuator in an emergency. Nine sizes cover 390 to 16,000 Nm with ratios from 26:1 to 420:1. The precisely cast housing offers multiple material options, while the self-locking worm gear pair and bearings keep transmission smooth and efficient. Valve-side mounting follows ISO 5211; IP65 as standard, IP68 optional. Manufactured in compliance with CE and ISO 9001 standards.

Standard Type: Quarter-turn
Gear Type: Worm Gear
Ratio: 26:1–420:1
Torque: 390–16,000 Nm
Protection: IP65 (IP68 optional)
Housing Material: Ductile Iron, WCB (common)

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Product Features

Declutchable design switches between manual handwheel and pneumatic actuator operation
Self-locking worm gear set prevents valve back-driving
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

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Custom Solutions

Housing materials: Ductile iron, WCB, CF8/CF8M, LCC, LCB, LC1
Handwheel & chainwheel size customization
Pneumatic actuator connecting flange customization
Worm gear hubs customization (Valve stem)
MSS flange standard or custom connections
C5 coating system
IP68 protection option

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Technical Parameters & Dimensions

Read our selection guide: How to Choose a Valve Gearbox for Industrial Valve Applications

(Tip: Hold Shift and scroll the mouse wheel to scroll the table horizontallyPinch to zoom the table, double-tap to reset)

Dimension Drawing A · B · E · G · H2 · F · H · Handwheel Φ · A0×A1 · PDC(D2) · Φd1 · Bore · Key · PDC(D0) · Bolt

YOYAGE MY-F pneumatic declutchable worm valve gearbox dimension drawing with ISO 5211 mounting flange and cylinder connection details

Technical Parameters, Connection & Appearance Size

Model	Ratio	Input TorqueN·m	Output TorqueN·m	Cylinder ConnectionA0×A1	Bolt Circle Dia.PCD D2	Bolt Holes4-Φd1	Bored	Keyb×h×n×90°	Bolt Circle Dia.PCD D0	BoltN-M	A	B	E	G	H2	F	H	HandwheelΦ
F26	26:1	60	390	68×68	70	4-Φ9	22	8×7×2	70	4-M8	222	170	84	133	87	106	85	200
F38	38:1	60	550	110×110	102	4-Φ12	32	10×8×2	102	4-M10	265	203	97	159	96	126	90	200
F38	38:1	75	620	110×110	102	4-Φ12	38	10×8×2	102	4-M10	265	203	97	159	96	126	90	250
F54	54:1	120	1200	130×130	140	4-Φ18	48	14×9×2	140	4-M16	295	220	123	201	108	173	100	300
F80	80:1	140	2000	157×157	165	4-Φ22	60	18×11×2	165	4-M20	395	280	165	283	132	235	125	400
F78A	78:1	200	3500	161×161	165	4-Φ22	76	20×12×2	165	4-M20	465	324	185	325	136	282	130	500
F100	100:1	200	5000	235×235	200	8-Φ18	80	22×14×2	200	8-M16	590	445	160	350	143	300	118	500
F320	320:1	200	8000	290×290	254	8-Φ18	85	25×14×2	254	8-M16	655	510	168	385	255	300	200	500
F420	420:1	200	16000	350	298	8-Φ22	100	28×16×2	298	8×M20	720	530	209	470	283.5	350	250	600

Need MY-F Series Selection Support?

Send your valve type, torque requirement and pneumatic actuator details to the YOYAGE team for MY-F selection and quotation.

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MY-F Series Manual / Pneumatic Declutchable Quarter-turn Worm Valve Gearbox