Worlds First ATEX Approved Pneumatic Brake Motor
Explosion prevention is a hot issue within the field of systems engineering. Friction, overheating or sparks could lead to a horror show in potentially explosive environments.
Brake motors are essential in stopping loads in case of power failure or danger of injury, but the solutions for hazardous (explosion risk) areas are very limited and expensive.
DEPRAG, one of the leaders in the field of air motors, has mastered this challenge with an innovative drive system. DEPRAG engineers have developed an entire system with exposed parts made out of stainless steel, consisting of motor, brake assembly and gears. It corresponds with ATEX standards and was specially developed as a safe drive for vat drainage equipment from Beer-Fördertechnik. The equipment provides vat drainage of toxic powder materials with grains smaller than 100 µm, a bulk weight of 0.86 kg/l and ignition energy of less than 20 mJ. This motor technology is now available as a standard product.
Wilfried Beer, managing partner of Beer Fördertechnik speaks enthusiastically of the immense advantages of this new type of brake motor. “By using this complete system for my vat drainage equipment, I can save myself enormous additional construction and manufacturing expenses because the brakes, which provide the safety for my mechanism, are already integrated.”
The integrated brake, which acts as a holding brake, is comprised of three brake disks, a pressure spring and a piston. They are controlled separately using an airline. When the control line has a pressure of over 5 bar the brake is released. If the pressure drops below 5 bar it is engaged.
Here is the difference. A normal brake has a grey area, where if the control line pressure is close to the compression force of the spring the brake can slip which would cause dangerous levels of heat, thereby elevating the risk of explosion in a hazardous area.
To produce a motor, which could be authorized for use in potentially explosive environments, DEPRAG engineers had to think outside the box. Mr Gerd Zinn, Manager of the Serial Machine Development Department said: “By implementing a safety valve, we have minimized this risk.” The valve turns the air feed off automatically when the pressure falls under 5-bar, causing the pressure applied to the brake to become zero. The brakes are then forced together fully and the motor is blocked.
The new motors are now available in various torque ranges and speeds in the 1.2 kW stainless steel motor-program from DEPRAG. They comply with ATEX guideline 94/9/EG corresponding with: EX II 2GD c IIC T5 (95°).
DEPRAG SCHULZ GMBH u. CO. has its headquarters in Amberg, Germany and is a leading international provider of air motors, automation, screw-driving technology and air tools. The company is represented by 600 employees in 39 countries around the world and since 1931 has offered a full service portfolio for almost every industry.
Assembly Technologies Pty Ltd are the Australian representatives for all of Deprag’s products.
