Modifications are a complex, but effective component of conveying applications. Modifications that are designed correctly can enhance performance in synchronous and non-synchronous product handling applications.
With nearly limitless design options, modifications can be made to both the conveying and drive sides of the belt. By changing the construction, material, or finish of the belt, manufacturers can better meet their unique product handling requirements.
Types of Belt Modifications
Depending on the desired capability — whether it’s enhanced speed, increased traction, or higher resistance to wear — various modifications are available for optimizing belts to meet the demands of your specific application. Common modifications include:
Punching / Perforating
Using precise tooling for exact diameter and hole spacing, manufacturers can punch and perforate holes in a belt to allow air to pass through it. This creates suction, which better holds objects in place as they move along the conveying path. Although this method is most often employed to achieve a vacuum or suction effect, it can also be used to vent water.
Countersinking, Slotting, and Routing
Countersinking is used to enhance the suction effect of solely using perforation. This modification, which creates a conical shape on the top side of the belt, expands an existing hole, allowing air to make better contact with the product. Both slotting and routing increase the area of suction, thereby creating better vacuum
The primary purpose of siping — creating sipes or slits in the belt — is to provide stress relief. Siping helps prevent cracking in the belt, especially if it has a thick cover or if it is traveling over a smaller pulley. These slits are etched across the width of the belt, either laterally or diagonally. In addition to providing relief, siping also helps to prevent the cover from dusting or glazing over. Furthermore, wider diagonal grooving of the belts cover can allow for venting or release of water in certain applications
Milling / Grinding
Using precision multi-axle CNC machining equipment, milling and grinding — the most complex modifications of all — can be done on both sides of a belt to achieve various results. Tooth-side grinding involves removing an area of the belt’s teeth for one of two reasons: to create a leak-free suction seal when riding over the vacuum chamber or to provide the belt with an integral tracking design.
Grinding the belts cover side can also serve many purposes; it can give the belt a new texture or finish, alter the thickness of the cover, or modify the cover profile — by creating lugs, for example. Precision grinding the cover side brings uniformity to the belt’s different thicknesses and textures, depending on what types of objects it will be moving and the level of control required.
When making multiple modifications on the same belt, the complexity of belt, the features required and stacked tolerances must be taken into consideration. Generally, the customization process begins with the base timing or flat belt, followed by the addition of a molded, fabricated or coated cover, which can then be further altered with CNC-machined features such as slots, holes and ground impressions.
Belt Modification in Action: A Case Study
To illustrate how modification can impact a project, we’ve outlined a relevant case study below.
A corrugated box manufacturer needed to find an aftermarket supplier for the replacement timing belt on a paperboard handling machine. Unable to justify the high cost and long lead time of an OEM replacement part, the company turned to Megadyne Belt Corporation for an alternative solution.
After receiving the original geometry and surface characteristics of the belt, we developed a series of prototypes to reverse engineer a replacement part that not only matched the complex criteria, but was also cost effective. To keep costs down, we made sure our fabrication methodology was as efficient as possible, producing nine belts per machine.
The belt, a neoprene base with a 0.125-in.-thick gray, non-marking Neoprene cover, featured precision-ground teeth with slots machined into the cover, as well as holes in the slots for vacuum suction. Utilizing a combination of routers, grinders, and perforators, our team was able to match the original part’s tooth geometry and dimension as well as spacing of the slots and holes while maintaining tolerances of ±0.01 in.
After just six weeks, the 1200-8M-85 HTD timing belt was complete and delivered to the customer. Our final aftermarket product, which is used in corrugated box equipment, performs just as well, if not better, than the OEM belt we modeled it after. Megadyne Belt Corporation’s efficient production processes enabled us to provide our customer with a high-quality belt at a fraction of the price.
Want to Learn More?
To optimize product handling performance, your belt modification partner should have extensive knowledge and expertise. Belt Corporation, a member of the Megadyne Group, offers over four decades of industry experience and a broad range of materials and engineering capabilities to successfully mold, wrap, punch, slit, grind, and create virtually any belting configuration.
Let us help you get started on your next project. To discuss your unique belting needs, contact us today.