Special equipment design; special equipment manufacturing; special equipment installation, modification, and repair; road motor vehicle production. General items: Special equipment sales; general equipment manufacturing (excluding special equipment manufacturing); manufacturing of refining and chemical production special equipment; sales of refining and chemical production special equipment; manufacturing of gas, liquid separation and purification equipment; sales of gas, liquid separation and purification equipment; metal product repair; mechanical equipment research and development; mechanical equipment sales; goods import and export; engineering technical services (excluding planning management, survey, design, and supervision).