Van der Graaf Drum Motor Options

All units are available in all stainless steel construction, including end caps, shell, shafts and junction box.

Many combinations are available, please contact your Van der Graaf technical representative for details.

Thermal overload protectors are devices, embedded into the motor windings (one per phase) and are available for both Class F and H insulation. These protectors are a bi-metal type, maintaining continuity under normal temperature conditions.

When temperature within the motor rises above 135°C for Class F and 165°C for Class H, the GVTHERM will function, causing an open circuit between the respective GVTHERM leads (yellow).

For their proper operation, it is necessary to wire the GVTHERM leads to the motor starter. Connecting the two GVTHERM leads in series with the coil of the electromagnetic contactor will result in power interruption to the motor, when motor temperature exceeds 135°C for Class F and 165°C for Class H, thus protecting the motor from thermal overload.

No Belt design series drum motor is mandatory for application without a full belt contact to the drum motor or using modular belt which do not have the ability to dissipate the heat generated by the drum motor. The NB series drum motor should be specified when:
      a) the conveyor belt covers less than two thirds of the overall face width
      b) modular sprockets are attached to power modular belting
      c) no conveyor belt is used
Please contact your Van der Graaf representative for application assistance.

V-Grooves are available on all Van der Graaf drum motors. The v-groove is machined into the shell for optimal tracking; single or multiple v-groove locations are available. If lagging is required then a 1/8" maximum thickness is available to minimize chance of v-guide climb out. Please consult Van der Graaf for custom groove profiles.
View/Download V-Grooves Dimensions

Machine crowned (convex) shell tracks on all points of contact maximizing belt traction and extending belt life. Drum motors are available in a variety of shell crown and finishes.
View/Download Shell Crowns and Finishes

Van der Graaf offers a complete line of 'hot bond' and urethane laggings. Hot Bond lagging, better known as vulcanization actually cures rubber, wrapped to the desired thickness around the shell of the drum motor, under high-pressure and high-temperature. The result is a seamless, durable and tear resistant lagging. Urethane lagging is a two part ribbon flow cast method which pours liquid urethane directly on the shell. The shell finish prior to urethane lagging is prepared by a patented spiral groove to aid in adhering the urethane to the shell. Various finishes are ground smooth to avoid any type of product contamination.

A variety of finishes are available in 1/8", 3/16", 1/4", 3/8", 1/2", 3/4" and 1" thickness. Non-standard thickness requirements are available upon request.
View/Download Lagging Types, Profiles and Description

For motor limiting temperature Class of 180°C. By providing a higher insulation Class, the electric motor is able to withstand a higher ambient operating temperature.

The drum motor with an all-internal electromagnetic brake (RTM) provides accurate and positive stopping engagement. The motor and all rotating components come to a complete stop when power is disengaged. When power is engaged, the brake releases, allowing the motor to operate as designed. The RTM drum motor is bi-directional and ideal for cycles up to 40 starts and stops per minute. Typical applications include baggage handling, manufacturing and assembly lines, palletizing and package operations, among others.

The patented Clutch Brake Drum Motor (CBTM) provides maintenance-free operation in high indexing conveyor applications, up to 80 starts and stops per minute. The clutch brake allows the internal drum motor to run continuously and engages the pulley shell only when conveyor movement is desired. High levels of conveyor drive are often found in wide variety of applications, such as: baggage handling, manufacturing and assembly lines, document/package handling and palletizing and packaging operations, among others.

The CBTM drum motor equipped with the clutch brake eliminates the in-rush current that is a common cause of heat generation in the conveyor drive. Disengaging the clutch brake module allows the motor to continue running while the drum is stopped, eliminating the in-rush current, minimizing heat build-up which prevent overheating. A cooler running drive is energy efficient and reduces operating costs. Allowing the motor to run continuously also extends service life. The drive moor and clutch brake components are all housed within the shall and are bathed in oil.

The patented Manual Release Backstop (MRB) dramatically reduces the time and physical effort needed to reverse inclined conveyor direction. The MRB device has the ability to disengage an internal backstop allowing the drum motor drive to move freely in the reverse direction so that the belt can be unloaded. Drum motors with the MRB device can be implemented on both new and existing inclined conveyors.

Incline conveyors are designed to operate in the upward direction. However, at times it may be necessary to unload the conveyor belt, i.e. power outages, downstream backups or jams, etc. The MRB can be easily disengaged allowing the belt to roll back for easy unloading.