October 1, 2010
Put safety first during routine conveyor belt repairs.
By Patrick Mukushina
When it comes time for conveyor belt repair, the most important part of the process is often the most overlooked. Safety is of utmost importance on the job site every day, as well as during a belt repair. Workplace accidents are painful to both workers and the bottom line. A simple cut can add up, affecting productivity and, oftentimes, resulting in medical bills and a workers’ compensation claim.
In addition to wearing personal protective equipment, preparing the machinery that will be worked on using appropriate lock out/tag out procedures, as well as making sure you’re secured to a sturdy structure, following the proper procedures, and using the right products, is an essential part of a safe and successful belt repair.
Clamping the belt is a necessity every time you repair a belt. It doesn’t matter if you are 10 feet off the ground or 100 feet off the ground, clamping is one of the most important safety precautions you can take during a repair.
Serious injuries are possible when clamping is done without using the proper tools and products. Oftentimes, people will use a c-clamp and lumber to hold their belt. While that may seem attractive for a quick fix, many things can go wrong. Lumber will bend easily, leading to only two points of contact with the belt. C-clamps are also prone to slipping, which may cause injury or a delay in repairs if the belt falls to the ground.
Belt clamps are designed to work specifically with conveyor belts. Made with durable materials, they are more reliable than a piece of lumber that can easily snap under pressure. Belt clamps provide even tensioning across the entire belt width. They are also available in a variety of sizes so that you can choose the right one for your belt. Finally, many quality belt clamps now feature “safety pins” — retaining pins that prevent the scissors from slipping off of the clamp bar.
The importance of a squared cut
When working against a tight maintenance deadline, it is essential to avoid skipping a step, such as squaring the belt. Only a few minutes of time can make or break the accuracy of your splice. An accurate, squared cut will enhance belt and splice performance and ensure that the belt tension is distributed evenly across the belt. It also discourages mis-tracking, which can occur when a cut is made on an angle, causing the belt to wander.
There are a few different options when it comes time to actually cut the belt. The knife is an attractive option because it is readily available and inexpensive; however, it can be a safety and accuracy nightmare. Working with an exposed blade always presents a safety hazard, and when you pair that with the several passes it takes to complete the cut, it increases the risk of injury. Multiple passes with the knife also diminish the chances that you will have a straight and accurate cut. Even if you’ve squared your belt, if the cut is incorrect, mis-tracking will occur.
There are two main options when it comes to belt cutters — hand-powered and electric. Either is acceptable because they are both specifically designed to cut a belt. Finding a belt cutter with an enclosed blade is a big safety advantage since exposed blades are dangerous. And since a good splice can’t be achieved without a good cut, accuracy is also a big factor.
The hand-powered cutter tends to be the most accurate of the cutters because of its sturdy construction and straight, perpendicular cuts. An electric belt cutter has its advantages as well. Lightweight and portable, electric belt cutters are capable of quick and accurate horizontal and longitudinal cuts of all lengths. While it requires a power source, operator fatigue is reduced greatly and one pass can cut up to 2 inches into the belt.
Why skive the belt?
Along with squaring the belt before cutting, skiving the belt is an area that is often missed during the repair process. While skiving isn’t a necessity in terms of safety, it is a necessity in terms of maintenance. Skiving the belt reduces the splice profile for a better interaction with cleaners and the rest of the conveyor system.
How you skive and the equipment you use is very important. Handmade skivers often consist of a knife or a blade and are not recommended. When you don’t have the proper equipment to measure the skive, you run the risk of cutting into the vital carcass fibers. This may cause injury and downtime in the future and significantly reduce the life of the splice.
When choosing a skiver, look for a compact, lightweight model for working in cramped spaces. Much like choosing a belt cutter, an enclosed blade is preferred for safety purposes. Finding a skiver that allows you to set the proper depth and width is vital. In addition, it is important to measure the cut from the most worn part of the belt. Removing the top cover of the belt does not compromise the strength of the belt, but cutting the carcass will.
A complete splice
In the end, a splice is only as good as the products that are used to complete it, including fasteners. You will want to ensure that the fasteners are appropriate for the belt in question, keeping a few factors in mind. Fasteners should be chosen based on the PIW (pounds per inch of width) of the belt, the thickness of the belt, the minimum pulley diameter, and the type of material that is being transported.
Most importantly, it is essential to remember that your conveyor belts and components work as a complete system. Choosing products that work together as a complete system is integral to the performance and safety of the conveyor belting in your plant. Routine maintenance of these products is the hallmark of any great safety program — saving you time, money, and injury. AM
Patrick Mukashina is a product manager at Flexco.