Sequencing circuit in hydraulics |Application of Sequencing Valve |Sequencing of hydraulic Actuators

Summary

This video delves into the workings of a sequencing wall, a hydraulic pressure control mechanism used to regulate the operation of two or more actuators in sequence. It prevents simultaneous extension of cylinders by allowing the one with the least resistance to extend first. The video illustrates a practical application where a clamp cylinder secures a workpiece before a drilling cylinder begins its operation. The sequencing wall ensures the clamp cylinder fully extends before the drilling cylinder starts, maintaining the correct order of operations.

Takeaways

• 🔧 The sequencing wall is a pressure control device used to operate two or more actuators in sequence.
• 🛠️ It is designed to force cylinders to operate in a sequence where the one with the lowest resistance extends first.
• 🔄 The sequencing wall allows flow to a branch circuit instead of sending it back to the tank, facilitating controlled operation.
• 🚧 The component includes an external drain line, which must be connected to the tank for the circuit to function properly.
• 🔩 In a parallel setup without a sequencing wall, both cylinders would extend together, but with it, they operate sequentially.
• 🔨 An example application is a hydraulic circuit where a clamp cylinder extends first to hold a workpiece, followed by a drilling cylinder.
• 🛡️ The sequencing wall ensures that the clamp cylinder extends completely before the drilling cylinder begins its operation.
• 📈 The wall must be set at a high enough pressure to open only after the clamp cylinder has fully extended.
• 🔧 During retraction, the check valve allows the sequencing wall to be bypassed, enabling smooth operation.
• 🔧 The hydraulic circuit includes components such as a razor wire filter, pump, pressure relief valve, and direction control valves.

Q & A

What is a sequencing wall?

A sequencing wall is a pressure control valve used to force two or more actuators to operate in a sequence, ensuring that one actuator operates before another.

How does a sequencing wall control the operation of actuators?

The sequencing wall allows flow to a branch circuit when a certain pressure is reached, enabling one actuator to operate before another by controlling the flow of hydraulic fluid.

What is the purpose of the external drain line in a sequencing wall?

The external drain line in a sequencing wall allows for the connection of a line from the sequence wall's drain port to the tank, ensuring proper fluid flow and pressure management.

Why is it important for the sequencing wall to open only after the complete extension of the first actuator?

It is important for the sequencing wall to open only after the complete extension of the first actuator to ensure the correct sequence of operations, preventing the second actuator from operating before the first has completed its task.

What is the role of the check valve in the sequencing wall?

The check valve in the sequencing wall allows the flow to bypass the sequencing wall in the reverse direction, enabling the system to retract the actuators in a controlled manner.

Can you explain the scenario where a clamp cylinder extends first to hold a workpiece, followed by a drilling cylinder?

In the described hydraulic circuit, the clamp cylinder extends first to hold a workpiece securely in place. Once the clamp cylinder has fully extended, the sequencing wall opens, allowing the drilling cylinder to extend and perform the drilling operation on the workpiece.

What is the function of the pressure relief valve in the circuit?

The pressure relief valve in the circuit is used to prevent excessive pressure buildup by releasing hydraulic fluid when the pressure exceeds a preset limit, ensuring the safety and proper functioning of the system.

How does the direction control valve interact with the sequencing wall in the circuit?

The direction control valve is used to control the flow of hydraulic fluid to the actuators. In conjunction with the sequencing wall, it ensures that the clamping cylinder extends first and then retracts before the drilling cylinder is allowed to extend.

What is the significance of the normally closed direction control valve in the clamping operation?

The normally closed direction control valve ensures that the clamping cylinder does not extend unintentionally. It only allows fluid flow to the clamping cylinder when the valve is activated, which is crucial for precise control of the clamping operation.

How does the sequencing wall ensure the correct sequence of operations in the hydraulic circuit?

The sequencing wall ensures the correct sequence of operations by maintaining a closed position until the pressure in the system reaches a level that indicates the first actuator (e.g., clamp cylinder) has fully extended. Once this condition is met, the wall opens, allowing the second actuator (e.g., drilling cylinder) to extend.