Gast 4AM-70C-CB20 Gear Motor

A reversible, 1.1 HP (0.82 kW) air gear motor featuring an 8-vane design and a 20:1 worm gear reduction. It provides a maximum torque of 480 in-lb and is an intrinsically safe choice for hazardous industrial environments.

Description

The 4AM-70C-CB20 is a versatile power solution where electric motors are impractical due to heat or explosion risks. Because it is powered entirely by compressed air, it is ATEX certified (Group II, Cat 2) for use in explosive atmospheres.

The 8-vane configuration is a key technical differentiator; it provides more consistent torque and smoother rotation at very low speeds (inching) compared to standard 4-vane models. Its cool-running design allows it to operate in ambient temperatures up to 120°C (248°F) without risk of burnout.

Brand

GAST

GAST 

Since 1921, Gast Manufacturing, Inc. has been a leader in the design and manufacturing of quality air-moving products. We specialize in offering cost effective solutions for a wide variety of industries including industrial manufacturing, healthcare, and environmental cleanup applications.

Features

  • 20:1 Worm Gearbox: Efficiently converts high-speed air motor rotation into usable low-speed torque (150 RPM max).
  • 8-Vane Performance: Delivers superior low-speed stability and more reliable start-ups under load.
  • Reversible Operation: A standard 4-way valve allows for instant directional changes, even while running under full load.
  • Explosion Proof: Non-electrical operation makes it suitable for chemical plants, refineries, and vapor-heavy environments.
  • Stall-Safe: Can be overloaded or stalled indefinitely without damage to the motor or risk of electrical fire.
  • Right-Angle Output: Allows for flexible mounting in space-constrained machinery where an in-line motor won’t fit.

Specifications

FeatureSpecification
Maximum Power1.1 hp (0.82 kW)
Gear Ratio20:1
No Load Speed150 RPM
Max Torque480 lb-in (54 Nm)
Starting Torque @ 80 psi325 lb-in (37 Nm)
Max Air Consumption72 CFM ($122 m^3/h$)
Shaft Diameter1.125 in (1-1/8″)
Mounting TypeFace / Base

Applications

  • Industrial Mixing: Driving agitators for medium-viscosity fluids in chemical or food processing.
  • Conveyor Drives: Powering transport lines in “wash-down” zones or hazardous environments.
  • Winches & Hoists: Utilizing the gear reduction for controlled lifting in spark-sensitive areas.
  • Turntables: Rotating heavy industrial platforms or automated assembly stations.
  • Hose Reels: Retracting large-diameter industrial hoses in refineries or fuel depots.