Conveyor belt scrapers are an incredibly effective belt cleaning solution due to its ability to directly scrape product off along the conveyor belt.
They are normally the primary belt cleaning product on a conveyor system. However, not all scrapers are made the same.
Belt scrapers vary from one another in a multitude of ways. These differing factors include fitting arrangements, shaft size, length and composition, and blade size, quantity and composition.
The most popular choices in terms of blade composition are polyurethane and carbide. We analyse the considerations when deciding between these two materials.
Polyurethane is a polymer composed of organic units joined by carbamate links. To put it in plain terms, polyurethane is a type of plastic.
Polyurethane is used in many different types of applications and comes in all different forms.
For example, polyurethane is used to create the foam in foam sponges. It is also used to manufacture high resistance tyres. The applications for polyurethane are countless.
As a material, polyurethane can be customised depending on the chosen application. The chosen formula can be altered to suit many purposes.
Polyurethane is a softer material when compared to carbide and can be used on new, older or worn belts. It is particularly effective when the surface has become worn or uneven.
On a belt scraper, polyurethane blades are generally not tough enough to damage the conveyor belt itself and thus are more forgiving when something goes wrong.
As conveyor belts wear, deformities, cracks and dents are common occurrences. The polyurethane blades are able to wear into the shape of the belt in a reasonable time frame, thus maintaining effective cleaning through varying conditions.
The disadvantage of polyurethane is that the softer material has a faster wear rate. Polyurethane wears at a faster rate than carbide due to the differences in hardness, therefore polyurethane blades are made with greater wear allowance so as to obtain an acceptable wear life.
Carbide refers to any class of chemical compound in which carbon is combined with a metallic or semi-metallic element. For our purposes, carbide refers to tungsten carbide which is valued for its physical hardness, strength and resistance to chemical attack even at high temperatures.
Due to its high-resistance properties, carbide blades are chosen for heavy duty applications as the wear rate of the blades are low. However, the same properties can cause issues with worn or damaged belts.
The carbide blades do not wear into the shape as rapidly as polyurethane blades or give way to cracks and dents. This can cause the carbide blades to catch on any abnormality of the conveyor belt and cause damage to the blade mechanisms and the conveyor belt itself.
Carbide blades are generally the best for new conveyor systems when the belt is undamaged or unworn. As the belt becomes worn, carbide blades can be switched over to polyurethane when required.
Both polyurethane and carbide make excellent material choices for your blades. They are both strong, wear-resistant and long-lasting when compared to other materials such as rubber. However, it is critical that the decision is based off your specific operational needs.
When comparing polyurethane and carbide the main consideration is wear life and risk of wear, versus the application needs and the condition of the conveyor belt.
DYNA Engineering Belt Scraper Range
DYNA Engineering design, manufacture and supply a whole range of conveyor belt scrapers with varying blade types. Our range of DYNAFastFit® scrapers are constructed from stainless steel – making them rust and corrosion resistant and without subject to paint damage.
Engineered with retractable shafts for easy removal and maintenance and fitted with our patented DYNAFastFit® bearing housings, our scrapers deliver exceptional cleaning efficiency for a wide range of applications.
Most of our standard DYNAFastFit® scrapers are supplied with polyurethane blades, with optional modification to carbide (tungsten) blades.
For more information on our scraper range, check out our belt scrapers page. If you require more information on which blade type would suit your application best, contact us today at firstname.lastname@example.org
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