Faq's

Faq is the abbreviation for frequently asked questions. If you have any questions about drummotors, this is a good place to start looking for the answer.


What is a drummotor?
What about maintenance?
Can a Van der Graaf drummotor be run on an Inverter?
Is a Van der Graaf drummotor reversible?
Can a Van der Graaf drummotor be run without a Belt?
What are the maximum lengths available?
Do Van der Graaf manufacture drummotors run on 24V DC?
Can a Van der Graaf drummotor be lagged?
What worldwide ‘standards' are available?
What worldwide voltages/frequencies are available?
What if things go wrong?

 


What is a drummotor?

A Van der Graaf drummotor is a power transmission component that has been specifically designed to drive a conveyor with a rubber, pvc, polyurethane or plastic modular belt. All the components of a conventional conveyor drive assembly e.g. electric motor, gearbox, drive pulley (or chain), bearing blocks and bearings are replaced by the 'self contained' drummotor. The external shafts of the drummotor are ‘dead' (non- rotating) so it is very easy to install by just clamping the shafts into a frame. The electrical supply is direct to the stator (motor winding) without the use of slip rings or brushes via a heavy-duty terminal box mounted on the shaft end, or a cable through an IP67 sealing gland. The complete drummotor is sealed to a minimum of IP66 suitable for high-pressure wash down. Van der Graaf drummotors can also be supplied for continuous submersible operation (up to 2,5m deep) with IP68 sealing.

Back to top


What about maintenance? 

Van der Graaf drummotors are pre-filled at the factory with high quality oil suitable for 50,000 Hrs use (13+ years @ 10 hours/day). Oil can easily be changed without removing the drum from the conveyor (subject to conveyor design). No other maintenance is required.

Back to top


Can a Van der Graaf drummotor be run on an Inverter?

As the drummotor is oil cooled, running at lower speed/frequencies via an inverter drive generally means no ‘derating' of the drummotor is needed. In certain heavier duty applications it may be necessary to use a special winding wire (Quantum shielded) which gives better protection against ‘spikes' sometimes produced by inverter supplies. The speed range is 20 to 80 Hz (4-pole motors).

Back to top


Is a Van der Graaf drummotor reversible?

All Van der Graaf drummotors are designed to run either clockwise or anti-clockwise. On request a backstop is available.

Back to top


Can a Van der Graaf drummotor be run without a belt?

Generally our drummotors can be installed in applications without a conveyor belt (e.g as a rolling pin or a ‘nudge roller'). In some applications we may need to incorporate a ‘no belt' winding. For further information please contact Van der Graaf technical department.

Back to top


What are the maximum lengths available?

This depends very much on the application and the amount of belt tension/load to be applied to the drummotor. We have up to date manufactured drummotors up to 3.5m long. In contrast, the minimum lengths shown in the data sheets cannot be reduced.

Back to top


Do Van der Graaf manufacture drummotors to run on 24V DC?

We have a range of drummotors based around our TM138 (138.0 dia) that have been designed to operate on a 24V DC supply. The maximum power available is 0.75kW. These drums have been designed for high torque applicatons and use a shunt wound DC motor. Variable speed is also available.

Back to top


Can a Van der Graaf drummotor be lagged?

Lagging is generally used in wet applications to provide more ‘grip' between the underside of the belt and the drummotor. For larger drummotors, it is nearly always supplied to ensure that the available power can be transmitted effectively to the belt.
Van der Graaf can supply a variety of lagging types (Rubber, Nitrile, Polyurethane and Ceramic) and thicknesses based on the drum diameter and installed power.

Back to top


What worldwide ‘standards' are available?

Van der Graaf drumotors are CE marked but are also available in UL, CSA C US and USDA standards.
Drums are also available certified to Atex zone 22.

Back to top


What worldwide voltages/frequencies are available?

Van der Graaf can manufacture to suit any country worldwide.

Back to top


What if things go wrong?

All Van der Graaf drummotors from our TM100 thru' to TM620 are designed with bolted end-caps for user maintenance. If in the unlikely event a problem occurs, most local engineering or electrical rewind companies will be able to repair the drum quickly. Most specialist parts e.g. gears etc, are usually available within 24-48 Hrs worldwide.

Back to top