The Company I worked for is a professional oil drilling and production equipment manufacturing enterprise which integrates scientific research, development, design, manufacture and engineering technology service. It has the capacity of manufacturing various onshore oil drilling rigs, offshore drilling modules and various models of pumping units with drilling depth of 1000m to 12000m (450HP to 4000HP). Driving mode of oil drilling rig includes diesel direct drive, DC electric drive, AC variable frequency electric drive, mechanical-electric compound drive and mechanical transmission. The whole scheme, system module project, complete set of drilling rig, components of drilling rig, parts and all kinds of technical services are provided according to user requirement.The company has the sound management system and obtained API Q1 quality system certification issued by American Petroleum Institute and 4F, 7K , 8C and 11E monogram use permit .