The service friendly BASIC LINE air motor

Using an Allen key and tweezer, worn out vanes can be exchanged in next to no time – even by untrained personnel. After loosening the cylinder screws on the rear bearing cover and removing the end, vanes can be replaced quickly and simply. The whole job is competed within a couple of minutes and is therefore even faster than replacing the whole motor in the system. The reduced maintenance of the QuickVChange vane exchange system is not only an advantage over all known motors, it also saves valuable production time.

Vane wear results predominantly due to the working principle of the motor: The rotor turning an eccentric cylinder is set in motion. In the rotor slits there are vanes which are pushed outwards against the rotor cylinder wall by centrifugal force. Working chambers are created and sealed against each other. Through the expansion of the compressed air, pressure energy changes into kinetic energy and the motor rotates. Between the vanes and the rotor cylinder wall friction occurs – after extended periods of operation the vanes become worn.

Using a motor with lubricated air will increase the motor’s lifespan. The optimum performance and life-span is attained with 1-2 drops of oil per 1m³ air consumption. The quality of the supply air should correspond with ISO 8573-1. Nevertheless, all BASIC LINE motors can also be operated oil-free. However, an additional loss of power of 10-20 % as well as shorter maintenance intervals should be factored in.

Thanks to its operating principle, the air motor is perfect for applications in potentially explosive areas: The depressurisation of compressed air cools any frictional heat generated and thereby eliminates any risk of overheating and ignition of gases. In accordance with directive DIN EN ISO 80079-36:2016, the suitability of air motors for use in highly explosive areas must be proven. The type examination certificate awarded by an independent test laboratory guarantees the user that the BASIC LINE series can be used without question in accordance with ATEX II 2G Ex h IIC T4 Gb X and ATEX II 2D Ex h IIIC T130 °C Db X.  

The air motor is suitable for the “non mining” sector in device category 2. These machines reliably guarantee a high degree of safety and can be used in areas where a highly explosive atmosphere of gases, steams, mists (2G) or dust/air mixtures (2D) intermittently occurs. This corresponds with zone 1 and 21 and also includes zones 2 and 22. If the supply air quality is right, this robust motor can even be used problem-free in dusty environments without any affect to proper functioning. The internal excess pressure prevents the infiltration of dust and dirt.

Air motors are simple to regulate and have a wide spectrum of application due to their versatile features. The BASIC LINE vane motor is additionally characterised by its speed adaptation feature, which adjusts automatically according to load variations. When load is removed the air motor run at idle speed. If low load is conflicted, when there is low torque on the motor spindle, the working speed approaches the idle speed. The working speed is reduced as soon as the torque increases. At 50 % of the idle speed the air motor achieves its maximum power. The motor runs particularly efficiently in this working range.

Depending on the application, the speed can also be reduced by regulating the air volume by throttling the supply or exhaust air. Exhaust air throttling reduces the speed of the motor without noticeably reducing the power or torque of the BASIC LINE pneumatic drive. Whereas supply air throttling is used to reduce the power and torque as well as the speed.

The speed can also be regulated via the operating pressure. The technical data of the DEPRAG BASIC LINE air motor is based on an operating pressure of 6 bar. Each of these motors can be operated as needed between 4 and 6.3 bar so that power can be adjusted according to the application requirements. A reduction of operating pressure by 1 bar causes a torque reduction of 17 %. If the air motor is operated at 4 bar, the torque is reduced by 33 %. If the air motor is rotating too quickly or is too powerful then the speed can be adjusted by altering the volume of air, the operating pressure or a combination of both. If the motor should be operated at a lower operating pressure, forced start vanes are recommended.

The air motors of the BASIC LINE series are even reversible and therefore suitable for both left and right rotation.

In conclusion, the BASIC LINE air motor can be utilised in any non-critical production environment where a robust cast iron housing is sufficient. The customer has a wide range of options of BASIC LINE vane motors from which, according to the modular system, customer-specific uses can be developed and manufactured. The series is available in the performance classes 200 W, 400 W, 600 W, 900 W and 1.2 kW in a broad speed range. All BASIC LINE air motors are equipped with a feather key.