screw jack lift system, self jack system using screw jack,jack screw lift table, screw jack building block system, silo with beam lift system, screw jack lift system, hand crank lift systems using reducer parts include bevel gearboxes, screw jacks, flexible couplings, connecting shafts and pillow block bearing etc. Electric motor operated with high speed or low speed. For lightweight and short stroke adjustment, manual operation is avaiable. Compared with pneumatic cylinder lift systems or hydraulic table lift system, which has heavy duty-load capacity up to several hundreds tons, self locking-no need brake mechanism or others locking systems, precision positioning, easy to control according to your own design, synchronizing lifting, multi-units uniform travel speed, multiple screw jacks lift system arrangements, easy installation, maintenance free and long service life.