In this series on our blog, we'll go through each press type one by one and discuss their features, advantages, and disadvantages and how all those elements make them the right choice for certain applications. In this post, we'll focus on the defining characteristics of air presses and their recommended measuring systems.
Air Presses - Part 6
- Fast Cycle Times: Ideal for high-speed operations, air presses deliver quick actuation and reset.
- Moderate Force Output: Best suited for light- to medium-duty applications involving thinner gauge materials.
- Adjustable Pressure Control: Operators can fine-tune air pressure to match specific forming or punching requirements.
- Compact and Lightweight: Easier to integrate into roll forming lines with limited space.
- Clean and Low Maintenance: No hydraulic fluids are needed, reducing mess and simplifying upkeep.
- Consistent Operation: Delivers repeatable performance for tasks like punching, notching, or shearing in continuous forming processes.
- Energy Source Dependency: Requires a reliable compressed air supply for consistent performance.
Recommended Measuring Systems for Air Presses in Roll Forming 
- Pick-Up Fingers: A pick-up fingers measuring system is a mechanical method commonly used in roll forming lines to track material length and position for timing press operations like punching or notching. As the formed profile moves through the line, the pick-up fingers ride along the surface, rotating a wheel or shaft that translates movement into measurable linear distance.
When paired with an air press, this system can trigger the press at precisely calculated intervals based on material length, ensuring accurate placement of holes, notches, or cuts. It's a reliable, cost-effective solution for applications where tight synchronization between material movement and press actuation is required, particularly in systems without fully automated servo controls. - Positive Stop: A positive stop measuring system is a simple, yet highly accurate method used in roll forming lines to position material for press operations. In this setup, the material is advanced until it physically contacts a mechanical stop, often a fixed or retractable block, ensuring consistent and repeatable length positioning before the air press activates.
This system is ideal for start-stop roll forming lines or operations where the material can pause momentarily, such as for punching, notching, or shearing with an air press. It's especially effective when high precision is needed without complex electronics and is commonly used for short-run jobs or where minimal automation is required. While not suitable for continuous or high-speed lines, a positive stop system offers simplicity, reliability, and low maintenance for many air press applications. - Open Loop Measuring: An open loop measuring system in roll forming relies on predetermined calculations and encoder feedback, typically from the drive rolls, to estimate material position and length without direct verification. In this setup, the system assumes consistent material feed and uses motor revolutions or encoder pulses to determine when to trigger the air press for operations like punching or notching.
This type of system is commonly used in continuous, high-speed production environments where stopping the material is not feasible. When paired with air presses, open loop systems can offer efficient, low-cost automation, but they depend heavily on accurate material feed and tension control. Any slip, stretch, or variation in feed speed can introduce position errors, so open loop systems are best suited for applications where extreme precision is not critical, or where the material and line conditions are highly consistent. - Closed Loop Measuring: A closed loop measuring system provides real-time feedback on material position by using encoders or sensors directly in contact with the moving strip, ensuring highly accurate press activation. Unlike open loop systems, closed loop setups continuously monitor the actual position of the material and adjust control signals dynamically, compensating for variables like slippage, stretch, or speed fluctuations.
When integrated with air presses in roll forming lines, closed loop systems offer exceptional precision and repeatability for tasks such as punching, notching, or shearing, especially critical in high-speed or tight-tolerance applications. These systems are often paired with programmable logic controllers (PLCs) and motion control systems, making them ideal for automated, continuous production environments where quality and consistency are top priorities.
