Peter UlintzCounterbalance Systems—What Every Press Technician Should Know
April 29, 2024Comments
In general, stamping press operators are considered lower-skilled positions in many plants, even though the operator has an enormous impact on a business’ bottom line. Some operators control press lines that cost hundreds of thousands or millions of dollars, running dies that cost more than the average home. Operator responsibilities include improving productivity, maintaining product quality, minimizing downtime and protecting the integrity of the dies and press. For these reasons, traditional press operators increasingly receive training to become press technicians.
A press technician is more than an operator. A technician comprehends stamping processes in terms of degrees of rotation, feed angles, sensor-signal angles, feed velocity, pressure requirements, signal lag time and other technical aspects necessary to effectively set up and run a modern press line.
In my experience training press operators and technicians, many lack deep technical understanding in three crucial areas: counterbalance systems, managing press loads and pilot-release timing. This month’s topic: press counterbalance systems.
Understanding Counterbalance
Press-ram counterbalance systems can be found on all but the smallest presses. The purpose of the counterbalance system: offset or neutralize the weight of the press ram, its connections and the upper-die assembly.
A typical garage door represents a good example of counterbalancing. Torsion springs mount above the garage door (Fig. 1). Anyone having experienced a broken torsion spring knows firsthand that the weight of the garage door suddenly becomes enormous. When a garage-door spring breaks, there’s no stopping the downward travel of the door before it reaches the ground. Conversely, trying to raise the door usually requires more than one person, each exerting a great amount of force to move the door a small amount.
When replaced, garage-door springs also are adjusted to counterbalance the weight of the door. When properly adjusted, the door can be closed to the halfway position easily and held there with little effort (Fig. 2). Stopping the garage door’s upward or downward movement can be accomplished quickly and with little force. 
A properly adjusted counterbalance allows the shut-height-adjusting motor to rotate the adjustment screws more easily and prevent premature wearing. It also helps to reduce drive-train-gear wear and allow the press to operate more quietly, while also improving stopping time of the press. Safeguarding devices such as light curtains rely on repeatable ram-stopping times to safeguard against injury. Excessive stopping times can render these safety devices ineffective.
