The ETR251/46 gear rack drive is a low-maintenance, 
purpose-designed drive for opening and closing swinging-atmosphere vents in Venlo-type greenhouses. The combination of TR251/46 gear rack drive and aEP RW engine gearbox plays a part in an optimum greenhouse climate thanks to planetary gearbox accurate positioning of the air flow vents.
The self-supporting TR251/46 gear rack drive comprises a zinc-plated C-profile with a built-in compact gear rack drive unit. The TR251/46 equipment rack drive is mounted to a greenhouse gutter using the accessory clamp-installation forks or bows.
Thanks to the apparatus reduction stage (i-2.76) and the pinion of the TR251/46 gear rack drive, the drive torque is effectively changed into a optimum rack force of 4200 N. Track rollers in the C-profile and instruction blocks ensure stable extension and retraction of the rack. The drive shafts of the TR251/46 equipment rack drive have long, flat-sided journals. This makes it possible to fit drive shafts (prefab) fitted with weld/sleeve couplings or chain couplings, once the house units have been mounted. The drive shafts are locked in the couplings by the accompanying shaft retaining clips. The TR251/46 equipment rack drive is easy to maintain.
A ETR251/46 equipment rack drive with other C-profile lengths and rack lengths is on request.