How to Integrate Hydraulic Press Automation Systems Into Assembly Systems

As presses become more deeply embedded into larger assembly systems, it is becoming increasingly essential to collaborate with an automation specialist who has extensive press and product knowledge.

Hydraulic presses are among the most versatile production tools today, providing extensive control. However, integrating these automation systems into your overall system architecture can prove a real challenge.

Controlling Hydraulic Pressure

Hydraulic press systems utilize pressure to push and pull fluid. This is accomplished through hydraulic hoses that contain and guide the flow of liquid from one component to another within a hydraulic system.

Hydraulic hoses transport hydraulic fluid from sources (pumps) to controls and actuators that use it. To ensure their effectiveness, connections must be made with components which will contain and direct the flow without leaking or losing pressure necessary for their operation.

Typically, rigid tubing or flexible hoses with entry and exit points sized according to how much fluid will pass through them are used.

In many cases, fluid paths are linked with valves to prevent any leakage from occurring. The valves also regulate the pressure that goes through each component in a hydraulic system by opening and closing as needed.

Controlling Ram Travel

Controlling ram travel in a hydraulic press automation system is critical for safety and dependability. Multiple variables must be controlled, including speed, force applied and length of motion of the ram.

Rams can be operated in either a single-stroke or multi-stroke cycle. When operating multi-stroke machines, it's essential to regulate the time between each phase of ram movement.

To achieve this, a programmable controller provided programming segments and tasks to allow the user to program multiple cycles. These segments controlled the speed of the ram at various points during the press cycle, ensuring it would move rapidly when necessary and slow down once metal components were formed.

The new controller automatically reverses the direction of a ram when it detects that it has reached the work piece, helping prevent parts from out-of-tolerance and extending machine life.

Controlling Die Position

When designing a hydraulic press, it is essential to factor in your application requirements early on in the design stage. Doing this will guarantee that your system offers all the capabilities needed - such as return-on-pressure or dwell times - at no additional cost.

Another commonly requested yet rarely considered capability is the capacity to hold a specific force for an extended period, such as during compaction processes, bulge forming and impression forming applications. With proper circuit design you can configure a variable-volume pump system so it continuously supplies desired holding pressure over any duration.

The return-on-pressure stroke is one of the most versatile features available on a hydraulic press. It enables the ram to lower and extend until a preset force point has been reached, penetrate or form material, then retract back up towards its starting position.

Controlling Press Depth

Presses are an ideal example of a complex force-position control application that can benefit from using both PLC-based control and event step execution by a motion controller. This combination enables programmers to utilize the PLC for complex sequences requiring tight coordination as well as status monitoring so operating modes can be adjusted quickly.

Furthermore, the new automation system utilizes a reverse direction step based on measured pressure to guarantee precise positioning during press cycle. This prevents parts from coming out of tolerance and extends the life of the machine.

In addition to saving SMG time during changeover, the new system allows them to manage production recipes through an intuitive operator screen interface. Recipes contain essential process data which can be accessed by plant personnel for tracking job statuses, assuring consistent quality and reducing waste during machine tuning.