1.Hydraulic cylinder 2. Hydraulic cylinder block 3. Push rod 4. Locking lever 5. Shear pin 6. Guide pulley 7. Limit bolt 8. Left clip plate 9. Clip board connector 10. Collecting flange 11. Reset bolt 12. Ball valve drive rod 13. Arm-side ball valve 14. Primary seal 15.Locating pin 16. Stop plate 17. Tanker-side ball valve 18. Right clip plate
For structural details of DBV/ERC, see Fig. 4.
ERC manufactured by our company mainly consists of two parts, i.e. arm-side ball valve and tanker-side ball valve. Upon operation, the tanker-side and arm-side ball valves are connected to the tanker manifold flange and the loading arm, respectively, with the middle of the two parts clamped together. In emergencies, this device may function to disconnect the loading arm from the tanker manifold flange by separating the upper and lower ball valves. After disconnection, the arm-side part will remain connected with the loading arm, while the tanker-side part will remain on the tanker. Before the disconnection, the two ball valve parts are reliably closed to ensure no leakage of the loading arm and tanker.
ERC is driven by the hydraulic cylinder. It is installed on the arm-side ball valve. Extension and contraction of the hydraulic cylinder will be transferred via a push rod to control opening and closing of the clamp and the ball valve. The two ball valves are connected as a whole through the left and right clip plates, and a primary seal is provided on the sealing surface between the ball valves to prevent leakage of medium. Upon disconnection, the left and right clip plate will flip open to realize separation of the two ball valves.
Main components of DBV/ERC
Hydraulic cylinder: it is the primary executing part of DBV/ERC, and may convert hydraulic energy into mechanical energy through some mechanisms.
Ball valve: it is a major component in ERC, functioning to enclose flowing medium inside of the pipeline without leakage.
(Left and right) clamp: it is a connector of the two ball valves, functioning to secure tight compression and reliable sealing between the ball valves during operation.
Shear pin: it is a safety device used to ensure safety of the whole system and prevent disconnection in the system due to manual misoperation. Only when the shear pin is cut off can normal separation be realized. The shear pin cannot be reused after damage.
Control box: it is installed on the arm-side ball valve. On the control box, there are two tags used to indicate the connected and disconnected states of the loading arm. Upon loading and unloading of a tanker, the handle on the panel must be pushed to the connected position to make the ERC system work. It is a safety device used to avoid misoperation.
Primary seal: it is used on the connecting surface between the two ball valves to prevent leakage. Commonly it is a reinforced PTFE sealing ring or an O ring. The primary seal is a quick-wear part.