INTRODUCTION Lajvar hydraulic(L.H) – Ltd – , the first and biggest manufacturer of all types of hydraulic and pneumatic cylinders, and electro-hydraulic power units in Iran, was established in 1995 in Arak- Iran, and officially registered in 2000. Hydraulic sets are very important and valuable devices due to complicated and sensitive production technologies. The L.H main plant that has 21000 sqm area consist of 4500 sqm of roofed workshops and 1500 sqm official rooms, is placed in Talash Street, 5th km Tehran road, Hajiabad industrial estate. L.H Company with 70 experienced staffs, is able to offer services to industries acting in Steel, machinery, construction, petroleum, oil, gas and … fields. Producing goods in the highest quality, using best materials and modern equipment is main mission of L.H company in order to give highest level of satisfaction to its customers.