Industrial ovens play important roles in manufacturing many of the parts that are used to assemble finished automobiles. One of the most prevalent applications for industrial ovens in the automotive supply chain is to cure friction materials —namely disc brake pads and drum brake linings.
Friction material ovens are important for reducing glazing and eliminating impurities, such as bonding materials, in brake pads and linings. If industrial curing ovens didn’t perform these operations, brake pads and linings wouldn’t have consistent coefficients of friction across their surfaces.
The most critical feature for a curing oven is temperature stability throughout the oven chamber. This is controlled through the careful calibration of the heat source and the airflow pattern within the oven. Depending on the production requirements, electric, gas, or infrared heat could be suitable for an automotive curing oven. Generally, a continuous or indexing conveyor configuration is recommended in order to automate the curing process and speed up production.
Curing Ovens for Disc Brake Pads
After disc brake pads have been press formed, they need to be cured through heat treatment. Conveyor ovens are ideal since they are capable of moving pad assemblies through heating and cooling chambers in an automated manner. This both ensures proper dwell time and speeds up production by eliminating the need for manual loading and unloading of product.
The DTI-1171 scorch machine, designed to cure disc brake pads, has a three-minute scorch time.
Typically, an electric heating source is best for these applications, which require strict adherence to operating temperatures anywhere between 300ᴼ and 675ᴼF, because an electric heat source offers the greatest degree of temperature control.
A specialized type of industrial conveyor oven called a scorch machine (or scorch system) can also be used to manufacture brake pads. Scorching heats the brake pads to 600–700°C in order to evacuate gases and resins trapped in the friction material during mixing. Many OEMs use scorching because it helps reduce the time required to seat pads after installation.
Lastly, if a brake pad requires supplemental finishing, such as powder coating or the application of an adhesive, an infrared oven might be the best choice. Properly engineered with the right SCR (Silicon Control Rectifier) control system, an electrical infrared oven will offer the maximum flexibility when it comes to directing heat and varying heat intensity — useful if one has a plant that processes several different products that require different coatings, for example.
Curing Ovens for Drum Brake Linings
The curing process for brake linings is often more complicated than the one used to cure brake pads, as it requires several stages where temperature profiles need to ramp up and down during the curing process. This multi-stage process makes an indexing conveyor oven with several chambers ideal.
Electric heaters or gas burner systems can be utilized for brake lining curing ovens because both are good at managing temperature fluctuations. Temperatures reached in oven chambers during a brake lining curing process can range anywhere between 200 and 500⁰F.