Adjusting tension in a drive belt can be a lot like tuning strings on a guitar. That is given the right tools are at hand to provide correct tension readings on the belt, and accurate calculations to determine the tensioning parameters.

Both of those aspects are easily taken care of with Gates’ 508C Sonic Tension Meter and the Gates’ Design Flex®ProTM drive design software.

As Gates Australia Business Development Manager Iain Street elaborates, the 508C Sonic Tension Meter can determine precise tension in Gates’ v-belts and synchronous belts by inputting the required belt frequency, as well as three simple parameters: the belt mass, the belt width and the belt span length.

To determine the optimal belt frequency for any drive design, the Gates Design Flex®ProTM design software is the go-to tool for all drive engineers that can provide them with the required 508C Sonic Tension Meter frequency for any belt drive in a simple report. Manual calculation can also be used to determine the frequency.

But, as Iain points out, there are tips and tricks to using the tool correctly that can ensure accurate belt set-up. Firstly, he says the attachments on the 508C Sonic Tension Meter should be selected with due consideration for the application.

“The standard sensor for the 508C Sonic Tension Meter is a microphone that ‘listens’ to the vibrations in the belt. This is the same principle used for tuning guitar strings. You set the desired vibration frequency in the Tension Meter, tap the belt span to make the belt vibrate and bring the microphone sensor close to the belt without touching the belt. The green LED light will continue to flash until a signal is received by the sensor. After the signal is processed, the measured belt tension is displayed.”

However, for noisy environments where high level of ambient noise may interfere with the reading, Iain suggests replacing the microphone sensor with an optional inductive sensor.

“The optional cord type inductive sensor relies on a magnetic field rather than on sound waves. This allows tension measurements to be taken in both noisy and windy environments. For the inductive sensor to function, a magnetic field must be present on the belt. This can be easily accomplished by taping a small magnet to the back of the belt.”

There are other minute factors that Iain says can impact the accuracy of tension measurements. For example, tension measurement should occur at the centre of the belt’s span. Measurement too close to the pulleys can give false readings.

“Also, the Gates’ Tension Meter and our Design Flex®ProTM program are set up to be used on Gates’ products. When people use them on inferior belts, sometimes they don’t get accurate readings. And that’s why it’s important to always use Gates’ products!” Iain notes.

The Gates 508C Sonic Tension Meter is available as part of the Gates maintenance kits, accompanied by other tools and gadgets that facilitate easy drive installation and maintenance. In Australia, CBC branches are a key distributor for Gates’ power transmission belts and drive accessories.

Steve Hittmann, CBC National Product Manager for Mechanical Drive Systems, says the Gates EZ Align® laser alignment tool is often used in conjunction with the Gates Sonic Tension Meter while setting up drive systems.

“The Gates EZ Align® tool is an ideal tool when setting up any belt-pulley system. Using it, technicians can simultaneously monitor all three types of pulley misalignment, which are vertical, horizontal and axial misalignment, to increase alignment accuracy,” says Steve.

“Incorrect belt tensioning and pulley misalignment are the two major causes of belt failure in any industry. CBC and Gates have years of experience in providing technical support to help prevent premature belt failures. When facing any issues with their belt drives, we recommend our customers consult their CBC representatives, who can help resolve the issues in consultation with Gates.”


Hot Tip

Before beginning pulley alignment, examine potential causes of belt or pulley failure and correct them to prevent recurrence. Some causes of failure could include poor drive maintenance, environmental factors, improper installation, or operating factors.