A ship-lock system coordinates gates, valves and water-level changes. The cylinder hardware is only one element. A clear sequence of operation is needed so mechanical movement, hydraulic permissives and operator commands agree.
Write the state transitions before choosing controls
Map every actuator and sensor to a physical gate or valve. Record which moves may occur together, which must wait for confirmation and what the system does when a position signal is missing. Load-holding valves, pressure relief and manual recovery should be designed from those states. A Bosch Rexroth lock-drive case illustrates how equipment placement and maintenance access can materially affect the system layout; its specific solution should not be copied as a universal design.
Engineering checks
- Identify permissives for opening and closing each gate.
- Define allowable position mismatch and travel time.
- Review the response to power, sensor and hose faults.
- Provide safe access to local isolation and test points.
- Test the sequence with realistic hydraulic load and water levels.
Common mistake to avoid
Testing one cylinder at the factory does not prove the gate sequence in the installed lock. Site acceptance must include sensors, controls, hydraulics and mechanical constraints.
Data to send with an inquiry
- Civil and gate general arrangement drawings.
- Sequence narrative and signal list.
- Load versus position and operating pressure.
- Factory and site acceptance criteria.
Maintain a version-controlled sequence and record actual acceptance results for future troubleshooting. For related selection guidance, see our ship-lock hydraulic product page.
Field note
Use a cause-and-effect matrix for faults and interlocks. It should identify the initiating signal, expected valve and pump response, permitted operator action and the way the system returns to service. This makes the acceptance test reproducible after future control-system changes.
Technical references: Bosch Rexroth lock-drive case; Parker load-control valve guidance. Cover: original conceptual schematic, not a product photograph.