Limitorque JMB Series: Specialized Valve Actuators for Water & Wastewater Industry

Developed on the foundation of the legendary SMB series, the Limitorque JMB Series is the premier electric actuator solution from Nippon Gear, specifically optimized for water supply, drainage systems, and heavy industrial applications. With a design focused on durability and high safety, the JMB Series ensures stable operation in the harshest environmental conditions.

Technological Highlights of the JMB Series

1. Absolute Safety Transition (Interlock Switch)

Operator safety is the top priority for the JMB Series. The equipment is equipped with a standard interlock switch:

• When switched to manual mode (handwheel operation), the electrical circuit is automatically and completely disconnected.

• This absolutely prevents the risk of the motor starting unexpectedly during manual intervention, ensuring the safety of technicians.

2. Precise Stroke & Torque Control

• Limit Switch: Utilizes a unique intermittent gearing mechanism, ensuring the set stopping points remain constant without deviation over time. Stopping points can be configured at any position throughout the stroke.

• Torque Switch: Protects the valve and drive mechanism from damage caused by overload during excessive opening or closing.

3. “Ultra-Durable” Gear Drive System

• Premium Materials: Aluminum-bronze alloy worm gears combined with Chrome-moly steel worm shafts.

• Optimal Lubrication: The fully sealed gearbox is immersed in extreme-pressure grease, allowing for smooth operation, high load capacity, and an exceptionally long service life.

• Bearing System: A combination of ball bearings and tapered roller bearings enhances stability when subjected to high thrust from the valve stem.

4. Designed for High-Humidity Environments

Every JMB model comes standard with a grounding terminal and a Space Heater. This feature is critical for the water and wastewater industry, preventing condensation and ensuring internal electrical circuits remain dry and stable.

Practical Applications

The JMB Series actuator is perfectly compatible with:

• Direct Mounting: Gate valves, Globe valves, Sluice gates, and Hydraulic valves.

• Combined with Gearbox: Operating Butterfly valves, Plug valves, and Dampers.

• Sectors: Municipal water supply and drainage, wastewater treatment plants, thermal/hydroelectric power, and shipbuilding.

JMB Series Technical Specifications Summary

Smart & Easy Maintenance

• Independent Structure: The motor and worm gear system are separate, making motor replacement extremely simple without altering the valve position.

• Self-locking Mechanism: Prevents unintended valve movement when the motor is removed for maintenance.

• Removable Drive Nut: The two-piece drive nut design combined with a spline joint allows for quick replacement without dismantling the entire actuator or wiring system.