Correct initial elongation for conveyor and drive belts

Correct initial elongation for conveyor and drive belts

A correctly installed conveyor or drive belt significantly extends the life of a product. There are certain guidelines which can be easily followed in order to best care for your equipment.

Since the most seemingly minute details of installation can dramatically effect performance, I will summarize techniques for correct conveyor and belt tensioning which guarantee your ultimate benefit from the life of the product.

Correct initial elongation for conveyor and drive belts

There are a few basic prerequisites which must to be met before a conveyor or flat belt can be correctly installed. Correct installation comprises the following steps:

Checking the system, installing the conveyor belt, and finally, start-up and alignment.

Since belts and the parts that drive them perform different tasks, the approach to the installation of each product must be viewed differently.

Situation 1: Correct installation of a Habasit conveyor belt:

The tension of a conveyor belt is determined by feel. It is important to make sure that the driving pulley can drive the belt without slipping even under a maximum load. The minimum and maximum admissible initial elongation (initial tension εo) varies according to the elements of traction. These are easy to find in our Product Data Sheets at our website.

Benchmarks:

  • Polyester fabric            à min. elongation = 0.3% / max. elongation = approx. 1.0%
  • Polyamide fabric          à min. elongation = 0.5% / max. elongation = approx. 3.0%

Another alternative for optimally determining the belt tension is to calculate the required peripheral force. This can be easily calculated by entering the system parameters and selecting the belt using our new web-based calculation program Habasit SeleCalc.

Situation 2: Correct installation of a Habasit drive belt:

Unlike conveyor belts, the main task of the drive belt is to transmit power. An incorrect initial elongation (too low/too high) can quickly destroy the belt through overheating caused by slipping or bearing damage beneath an excessive shaft load.

In order to guarantee problem-free functioning and to benefit from the features of a drive belt, the following three factors must be defined:

  • Belt type
  • Belt width
  • Initial elongation

If one of these three factors changes, the belt must be recalculated.

Fortunately, Habasit offers its customers useful assistance through the new calculation program. Habasit engineers have also developed a selection aid to help choose the best belt type.

General: Conveyor / belt mounting – first-time installation

Before installing, I recommend tracing small measuring marks at a distance of e.g. 1000 mm on the un-tensioned belt. Use a ball-point pen and mark as accurately as possible. Do not place the measured length of the belt over the joining area.

Example:

Required initial elongation εo = 2.0%:
Measuring mark distance of un-tensioned belt: 1000 mm
Measuring mark distance of tensioned belt: 1020 mm

Once the belt has completed at least 1-2 revolutions, the distance must be measured again and corrected if necessary.

Having installed your quality equipment with accuracy and precision, you can now rely on the full advantages of your Habasit product. Please don’t hesitate to contact me with any questions or concerns during the installation process.

Read our Fabric Conveyor Belts Installation and Maintenance Guide to get more installation tips.

2017 June 1  |  Posted by

Karl Gausterer

Karl Gausterer has worked at Habasit in Austria for 28 years. He is part of the Technical & Product Innovation Management team with an expertise in fabric division, materials handling, textile, fabrication and customer training. Gausterer finds that each new days bring an interesting challenge and he sees every customer inquiry as an opportunity to build relationship. He speaks both German and English.