The ETR251/46 gear rack drive is a low-maintenance, purpose-designed drive for starting and closing swinging-environment vents in Venlo-type greenhouses. The combination of TR251/46 gear rack drive and aEP RW electric motor gearbox plays a part in an optimum greenhouse weather thanks to accurate positioning of the air 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 installed to a greenhouse gutter using the item clamp-installation forks or bows.
Thanks to the gear reduction stage (i-2.76) and the pinion of the TR251/46 equipment rack drive, the drive torque is 
effectively converted into a maximum rack force of 4200 N. Track rollers in the C-profile and guide blocks ensure stable expansion and retraction of the rack. The drive shafts of the TR251/46 gear rack drive have lengthy, planetary gearbox 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 gear rack drive is simple to maintain.
A ETR251/46 gear rack drive with other C-profile lengths and rack lengths is available on request.