Flat woven endless belts are used on a wide variety of equipment for many different applications and specific end uses. Their uses vary from extremely sensitive drive applications, such as instrumentation, recording devices and sensitive weigh-pan conveying applications, to light and medium duty uses, such as currency and check transports, film transports, paper handling and vacuum transporting sections of business and office machinery, all the way up to high speed grinding, spindle drives, wire drawing applications, woodworking equipment and textile machinery drives. The variety of possible applications require an extremely wide range of specific physical properties that will enable each belt to perform its task continuously, with good reliability throughout its life.

Features:

With the combination of various yarn types and multiple styles of weaving, we have a plethora of belting possibilities. Our most common style of belts are referred to as Stable, Semi-Stable, Semi-Stretch, Stretch.

There are a number of factors to be considered before selecting a particular belt style for a specific application. Two of the most important factors to be addressed are the type of drive configuration and the provisions for belt tensioning (or lack thereof). The first thing to look at is the number of belts required to satisfy the application requirements and the overall geometry of the belt path, including sizes and number of pulleys.

Types of Drives:

The next considerations are the allowable space to accommodate belt width and the type of pulley on which the belt will run. Is the pulley face open or are flanges used to retain the guide belts? Are any pulleys crowned for guidance and belt tracking? If so, what type of crowning is being used and how severe is the crown? What is the face width of the open pulleys or what is the dimension between the flanges? These answers are required for proper belt selection.

Not all belts are designed to withstand running against flanges. Most types of flat woven endless belts will track well over a minimum of pulley crowning. If flanges are required, always use straight sides at 90 degrees to pulley face surface and maintain sharp corners, minimizing any rounding which causes the belt to climb the flange.

Circular/radius crowns are preferred over bevels with flats.

For belts up to 3″ wide:

For belts up to 3″ wide:

Unless unusual tracking problems exist, minimum recommended crowning should be chosen, since ideal properties are developed through uniform belt to pulley contact. If an extreme crown is chosen for use with a stable belt, the full belt width will not be able to stretch and conform to the pulley crown, leaving the percentage of the belt width, not the pulley width. Crown choice is primarily affected by belt styles, installation tension and the degree of precision found in the machine drive alignment.

Any adverse conditions which the belt may encounter, such as extreme temperatures, hostile chemical environments or severe abrasion should be considered as should other specific properties required, such as specific belt thickness, anti-static requirements or FDA approval.

The length or circumference of a flat belt is measured along its inside surface, or along the surface contacting the pulleys. When drive details are not available, a close determination of the belt path length can be made by using a wire or a steel tape, pulled taut around the pulleys. This measured distance is referred to as the drive circumference. The actual manufactured belt length may vary from the measured distance depending upon the amount of built-in tension or elasticity required for the specific style of belt, and the type of tension or take-up available on the machine.

Two pulleys, Equal Diameters, open drive configuration:

Two pulleys, Unequal Diameters, open drive configuration:

Two pulleys, Unequal Diameters, crossed drive configuration:

Flat endless belts have a maximum operating or working tension equivalent 10% of their breaking or tensile strength. Total tension on a belt should never exceed the operating or working tension.

These tensions are illustrated as follows: