Vulcan-Vulcap Section Repair Molds Offer Cost Effective Truck and OTR Tire Repairs
Vulcan-Vulcap Section Repair Molds are the result of over 60 years of research and development by Vulcan. All models of the MV Series Mobile Section Repair Molds for OTR tires are patented. Section Repair Mold patents were first issued to Vulcan several decades ago. Our latest Section Repair Systems are our Flexible Vulcaflex® Systems with Vulcatouch® Controls.
The key to a good, cost effective tire repair is a true Vulcanizer repair. Rubber flows during curing in both the plug area and between the patch and inner liner of the casing. This rubber flow will fill any existing air pockets, which are dangerous in a repair, since these air pockets will expand as the tire heats up and therefore will lead to premature failure of the repair. As existing air pockets are filled, the result is a dense, sealed repair that will not leak or fail prematurely.
During the curing process in a fixed Mold, 45 lbs. of pressure per square inch is applied to the area of the injury from the inside and 30 lbs. from the outside of the tire. Maximum patch sizes range from 18″ x 20″ (45.7 cm x 50 cm) for the V-14 Truck Mold to 30″ x 30″ (76 cm x 76 cm) for the largest MV-40A OTR Section Repair Mold. A compression cure or mold is achieved due to the pressure applied to the patch. The total force applied in the smallest OTR Mold is 18,000 lbs. and 58,320 lbs. for the largest model. The result is a densely sealed repair that will not leak or fail prematurely.
Flexible Section Systems, like the Vulcan-Vulcap Vulcaflex® OTR Truck and Tractor Repair Systems will do a similar job. Flexible Systems are more labour intensive due to set-up and cannot provide the same pressure as rigid Section Molds do. The advantage however of a Vulcaflex® system is that the full OTR tire range can be repaired with one system with the proper accessories.
The results achieved in a Vulcan-Vulcap Section Mold is a good compression mold with adhesion values exceeding 100 between patch and tire due to pressure applied during curing. The use of uncured cushion with a semi-cured patch eliminates the problem of air pockets. The shape of the patch may not conform to the inside contour of the tire and therefore careful stitching should prevent most air pockets. It is important that the repair is done in the relaxed state of the tire. In other words, at the 3 or 9 o’clock position of the tire when it is resting on the floor. The use of patches as described above with proper heat, pressure and temperature applied in a Vulcan-Vulcap Vulcanizer assures optimum compression cure. This means no under-cure or over-cure of material.
During proper curing (pressures guaranteed by a Vulcan-Vulcap Vulcanizer), materials will flow, air pockets are eliminated and when the tire flexes and heats up during operation, there will be no tendency for the patch to leak or cause under-inflation. In a Vulcan-Vulcap Vulcanizer, the patch and plug are cured in a single operation. Relatively large areas of the tire depending on maximum patch size can be properly cured in a single operation.
Earlier models of Vulcanizers had solid cores or mandrels, which were heated. However, this method was replaced with the flexible models where air mandrels, internal and external airbags together with heatpads are used for a broad range of tire sizes. The old solid cores were only practical for a specific shape of tire, usually bias type, whereas the new method allows the system to conform to each tire (whether radial or bias tires) under repair.
Vulcan-Vulcap Vulcanizers will provide heat and pressure without distorting the tire. The MV series, although big for large tires, is still truly portable and reasonably priced. Time, temperature and pressure are the 3 critical elements to successfully vulcanize a repaired tire injury. All models of Vulcan-Vulcap Vulcanizers supply all 3 elements with their unique Section Repair Mold Systems. To repair today’s radial tires distortion free, Vulcan-Vulcap Section Repair Systems with inflated mandrel systems will supply:
It is important to remember that tire repairs rarely fail if the right time, temperatures and pressures are utilized during the repair/vulcanizing process. The art of repairing tires lie in the hands of the tire repair person, who must inspect, skive, cement and complete the repair properly. Vulcan-Vulcap Section Repair Vulcanizers will cure the repair and do the rest for a tire repair that will last as long as the tire will.