In the world of stamping automation production lines, heavy-duty decoilers play a pivotal role as essential material feeding and decoiling devices. There are two main types of decoilers: non-motorized and motorized. Despite the minimal space required for non-motorized decoilers, they are less popular due to their dependency on the leveling machine head’s traction. This reliance results in substantial motor wear on the leveling machine. Consequently, motorized heavy-duty decoilers dominate the market.

The Functionality of Motorized Heavy-Duty Decoilers

In stamping automation, feeders operate stepwise, adhering to the specific needs of the stamping process. Therefore, heavy-duty decoilers must synchronize with the start-stop operations of the subsequent leveling and feeding machines. Standard heavy-duty decoilers manage this start-stop function using a sensing rod installed on the machine’s side, which can be replaced with a floor-mounted sensing frame based on customer requirements.

Automation Control Principle

The automation control of standard heavy-duty decoilers is straightforward: the sensing rod carries a 24V DC voltage and is grounded to the machine frame. When the coil decoils and the material strip enters the next machine, it droops to a certain extent. If the droop becomes excessive and contacts the sensing frame, the 24V sensing circuit completes. This circuit, through intermediate and time relays, halts the machine’s operation. As the subsequent machine uses the material strip and it moves away from the sensing frame, the decoiler resumes feeding. This system allows for fully automated control of the decoiler’s start-stop operation, provided the surface of the decoiled material is conductive.

Challenges with Non-Conductive Materials

In various stamping processes, the materials used may not have conductive surfaces. For example, silicon steel sheets, coated materials, and non-metallic substances do not conduct electricity. Using standard heavy-duty decoilers with these materials prevents automated start-stop operation. To overcome this, the sensing device must be adapted to the customer’s specific needs. There are two primary modification methods:

Through-Beam Photoelectric Sensors

The first method involves using through-beam photoelectric sensors to control the decoiler’s automatic start-stop function. These sensors are installed at the desired start-stop height of the decoiler. When the decoiled material droops to a certain position and blocks the beam, the photoelectric sensor stops the decoiler. As the subsequent machine uses the material and it moves away from the beam, the decoiler resumes feeding.

Micro Switches

The second method uses micro switches to control the decoiler’s automatic start-stop function. The micro switch is fixed on a floor-mounted bracket, placed in the waiting area between the decoiler and the subsequent leveling and feeding machines. When the drooping material strip touches the micro switch, it sends a control signal to the intermediate relay in the decoiler’s electrical box, stopping the motor.


Motorized heavy-duty decoilers are indispensable in stamping automation production lines, ensuring efficient material feeding and decoiling. While non-motorized decoilers offer some advantages, their dependency on the leveling machine head’s traction limits their use. The advanced automation control of motorized decoilers, whether through sensing rods, photoelectric sensors, or micro switches, ensures smooth, synchronized operations, accommodating a variety of materials and enhancing overall production efficiency. Adapting these controls to specific material properties is crucial for maintaining seamless automation in diverse stamping processes.