| 摘要 |
PURPOSE: A main valve for a tank lorry is provided to improve the storage stability of oil with a simple structure of a main valve. CONSTITUTION: A main valve for a tank lorry comprises a coupling part(210), a cylinder part, a valve disk(260), and two connection pipes(270). The coupling part has an opening part and two holes. The opening part corresponds to a refueling hole of a tank. Air of fluid is injected or discharged through the two holes. The coupling part is coupled to the internal side of a tank. The cylinder part comprises a piston, a piston rod, and a cylinder body. The cylinder body has an upper hole and a lower hole. The upper hole is formed above a top dead center of the piston. The lower hole is formed under a bottom dead center of the piston. The valve disk opens and closes the opening part of the coupling part. |
