Hydraulic pump is an integral part of every hydraulic circuit. They are changing mechanical energy to  hydraulic energy. ( pressure and flow of fluids)

 

Gear pumps divide for pumps with internal and external gear. Gear pumps with external gear are the most popular pumps at producing of power unit.

 

External gear pumps sell from italien company called OT OIL Technology and internal gear pump sell from german company ECKERLE.