The electric heating conveyor belt vulcanizing machine is a key equipment used for vulcanizing and bonding conveyor belt joints. Its working principle is based on the synergistic effect of heat, pressure and time, and achieves the cross-linking and curing of rubber materials through precise control. The following analysis is conducted from three dimensions: core processes, key systems, and process requirements:
First, the core workflow
Temperature control system
The heating plate is heated to around 145℃ through electric heating elements (such as stainless steel electric heating tubes), and uniform temperature conduction is achieved by using a heating plate made of high-strength aluminum alloy.
The temperature control system supports both automatic and manual modes. It can preset the vulcanization temperature (0-200℃) and constant temperature time to ensure that the fluctuation range of the vulcanization temperature is controlled within ±3℃.
Pressure application system
Using the water pressure plate as the pressure source, the pressure medium is injected through the pressure test pump to form a uniform pressure of 1.0-2.0MPa in the vulcanization area.
The pressure mold box is equipped with a pressure indicating instrument, which can monitor and compensate for the elastic deformation of the crossbeam in real time during the pressurization process, ensuring that the pressure distribution deviation in the joint area is ≤0.5mm.
Vulcanization reaction process
Under high-temperature and high-pressure conditions, the sulfur cross-linking bonds in the rubber molecular chains are rearranged, completing the transformation from viscoelastic raw rubber to highly elastic cooked rubber.
The vulcanization time is dynamically adjusted according to the material of the belt (usually 30-60 minutes), during which the control system automatically maintains the stability of the temperature-pressure parameters.
Second, key system collaboration
Heating system
It adopts a double-layer heating plate structure, with an internal thermal resistor (or thermocouple) to provide real-time temperature data feedback. The temperature control unit achieves precise temperature control through the PID algorithm.
The heating stage requires no more than 50 minutes to reach the vulcanization temperature from room temperature, and the thermal efficiency is increased by more than 30% compared with traditional equipment.
Pressure system
The water pressure plate and the frame form a closed pressure chamber, and the linear loading and dynamic maintenance of pressure are achieved through the hydraulic system.
It is equipped with an automatic pressure replenishment device. When the pressure drop exceeds 0.1MPa, it will automatically start to increase pressure to ensure stable pressure throughout the vulcanization process.
Control system
It adopts a PLC programmable logic controller, integrating the interlocking control function of three parameters: temperature, pressure and time.
It has the ability of self-diagnosis of faults and can monitor safety indicators such as three-phase voltage balance and insulation resistance value (≥50MΩ) in real time.
Third, key points of process control
Joint pretreatment
The end face of the tape needs to be ground until the fiber layer is exposed. After applying the vulcanized adhesive slurry, a stepped lap joint is carried out. The lap length is dynamically adjusted according to the width.
Vulcanization parameter matching
Steel cord conveyor belts should adopt parameters of 1.5MPa/145℃/45 minutes, while fabric core conveyor belts are suitable for parameters of 1.2MPa/140℃/35 minutes.
Quality inspection standard
After vulcanization, the tensile strength of the joint should reach more than 90% of the original belt strength, the surface flatness deviation should be ≤0.3mm, and there should be no defects such as bubbles and delamination.
This equipment achieves molecular-level reconstruction of the conveyor belt joint through the precise coupling of the three elements of heat, pressure and time. Its technical advantages are reflected in:
Temperature uniformity: The aluminum alloy heating plate, in combination with heat pipe technology, has a temperature difference of no more than ±3℃ on the plate surface
Pressure stability: The pressure fluctuation of the water pressure system is ≤±0.05MPa
Energy efficiency ratio: The energy consumption per unit area for vulcanization is 25% lower than that of traditional equipment
Reliability: MTBF (Mean Time Between Failures) ≥8000 hours