In the current way of conveying materials, the belt conveyor is relatively safe, convenient, easy to maintain and low freight. Belt conveyors have been widely used in industry, agriculture and transportation. In addition to normal wear and tear, the conveyor belt may also appear abnormal wear, rupture or fracture due to objective or artificial factors, so the economic loss or casualties caused by accidents are difficult to predict.
The conveyor belt must be connected into a ring to use, so the quality of the conveyor belt joint directly affects the service life of the conveyor belt and the operation of the conveyor line. The conveyor belt produced by the original factory is usually fixed in length and specification. In order to meet the needs of conveyor belts of different lengths, it is necessary to combine the conveyor belt with specifications. Conveyor belt commonly used joint methods are mechanical joint, cold bonding joint and hot vulcanization joint. Practice has proved that hot vulcanization joint is the most ideal joint method at present, which can ensure high stability of joint efficiency and long service life. However, most of the conveyor belt joint hot vulcanizing machines on the market have shortcomings such as small vulcanizing area, limited vulcanizing conveyor belt specifications and small pressure.
This work designed for portable electric heating to the existing vulcanization vulcanizing machine conveyor belt joint area is small, can cure conveyor specification is limited and uneven pressure and problems such as portability, structure of main machinery and heating hot plate structure and the temperature control system for technical research, design a good applicability, high temperature control precision, easy disassembling of portable conveyor belt joint electric heat vulcanizing machine.
1 Key parts of vulcanizing machine design
This design mainly includes three structural modules :(1) the main machinery and heating structure design; (2) Hot plate structure design; (3) Design of temperature control system.
1.1 Main machinery and heating structure design
Portable conveyor belt joint electric vulcanizing machine is mainly composed of frame, hot plate, travel switch, pressure system, temperature control components, electrical control system and power supply system.
The frame plate (composed of the upper beam and the lower beam symmetrically arranged on the left and right sides respectively) and the hot plate are the key parts of the mechanical and heating structure of the portable conveyor belt joint electric vulcanizing machine. A hot plate is clamped between the upper beam and the lower beam (composed of heated aluminum plate embedded in the connecting plate), and the hot plate is composed of an upper hot plate connected side by side and a corresponding lower hot plate connected side by side. A conveyor belt joint is placed between the upper hot plate and the lower hot plate. The upper hot plate and the lower hot plate are heated to reach the purpose of extruding and heating the conveyor belt joint to achieve vulcanization operation.
1.2 Hot plate structure design
Hot plate is the heating component of portable conveyor belt joint electric vulcanizing machine. During the vulcanizing process, the conveyor belt is pressurized and heated. The uniformity of heating temperature distribution directly determines the quality of conveyor belt joint. The connecting plate of the hot plate is closely attached to each beam, and the connecting screw plays a role of fastening and transferring pressure.
In order to meet the requirements of embedding heated aluminum plate in the connecting plate, each connecting plate is designed with several grooves for placing the heated aluminum plate. In order to reduce the mass and accelerate the thermal conductivity, the heating aluminum plate is made of Ly11 high-strength aviation aluminum plate, which reduces the volume and mass of the hot plate by 50% and reduces the energy consumption while accelerating the temperature rise. After the temperature rises during vulcanization, the flexibility of the hot plate is better. Under 1.5MPa pressure, the gap between the hot plate and the conveyor belt is no more than 0.03mm, and the joint splicing effect of the conveyor belt is better.
1.3 Design of temperature control system
The temperature control system of portable conveyor belt joint electric vulcanizing machine adopts automatic electric control system, and displays directly with precision digital instrument and indicator light. Temperature control system functions include preset curing time and temperature, the whole curing process automatic control, through the warning lights to remind the completion of the operation.
The temperature control system adopts vertical double-layer waterproof technology, which can adapt to the operation of portable conveyor belt joint electric vulcanizing machine in sand, rainstorm, scorching sun and other external bad weather; Equipped with overload, short circuit, leakage protective automatic switch, to ensure personal safety.
2 Vulcanizing machine features and technical parameters
The characteristics of the portable conveyor belt joint electric vulcanizing machine are as follows.
(1) The smoothness of the joint is high. Conveyor belt joint (repair) forming, joint (repair) flatness and other parts of the conveyor belt almost the same, tensile strength can reach more than 98% of the (original) conveyor belt.
(2) heat evenly. The hot spots and temperature of the hot plate are evenly distributed. After the test, the temperature difference between the hot spots of the hot plate is about ±3℃ after heating to the vulcanization temperature and holding for 10 min, which exceeds the requirements of relevant standards.
(3) Rapid heating, low energy consumption. The heating time from room temperature to 145 ℃(vulcanization temperature) is less than 25 min, and the energy consumption is only 1/2 of similar models.
(4) The fitting degree of hot plate and conveyor belt joint is high. When the vulcanization temperature rises, the hot plate has good flexibility. Under vulcanization pressure, the gap between the hot plate and the conveyor belt is small, and the joint of the conveyor belt has good splicing effect.
(5) Simple structure, easy to transport disassembly. The volume and mass of the hot plate are reduced by 50%, and the structure of the whole machine is simplified and easy to disassemble and assemble.
2.2 Scope of application and technical parameters
The design of portable conveyor belt joint vulcanizing machine is suitable for metallurgy, chemical industry, energy, building materials and port conveyor belt joints and repair of the ideal equipment, the main technical parameters are as follows: heating power 15/11 kW, 220/38O V(50 Hz), Pressure mode – mechanical, temperature difference of hot plate surface ±3℃, heating time ≤30 min, conveyor belt width ≤1 200 mm, conveyor belt thickness ≤36 mm, conveyor belt joint length ≤600mm, conveyor belt joint cutting Angle 0°/16.7°, vulcanization temperature 125~ 150℃, vulcanization pressure 1.0~3.0 MPa , curing time 30~60 min, suitable for conveying belt skeleton material canvas, nylon, steel wire.
The design of the portable conveyor belt joint vulcanizing machine with removable assembly type mechanical structure fastening frame structure; The hot plate adopts the unique design of split type, and the heating aluminum plate selects light and high strength aluminum alloy, which is suitable for vulcanization of conveyor belt joints of various specifications and models, and the joints have high strength and good smoothness; Temperature control system adopts automatic precision digital display control system, hot spot and temperature distribution of hot plate is uniform; The whole machine is easy to transport and disassemble, reliable and durable. Part of the design of this machine fills the gap in China, is an ideal equipment for on-site conveyor belt joint and repair.