The conveyor belt of the strong belt conveyor is composed of multiple steel ropes instead of the canvas layer (or other materials) of the common conveyor belt as the core body, so the conveyor belt has high tensile strength.
Difference: Compared with the general belt conveyor, the main feature of the strong belt conveyor is the different structure of the conveyor belt. The conveyor belt of the strong belt conveyor is composed of multiple steel ropes instead of the canvas layer (or other materials) of the common conveyor belt as the core body, so the conveyor belt has high tensile strength. This kind of conveyer can realize single long-distance transport without reprinting, simplify the transport system, improve the transport efficiency.
Technical characteristics: The main technical characteristic parameters of strong belt conveyor are product specifications, conveyor capacity (t/h), conveyor length (m), conveying material type, conveyor belt width (mm), belt strength (N/mm), belt speed (m/s), conveyor belt steel rope core diameter (mm), number of roots, motor model, rated power (kW), rated voltage, reducer specification type Number, brake specifications, brake torque, etc.
Working principle: When the powerful belt conveyor works, the motor rotates through the reducer and coupling to convert the electric energy into the working torque of the driving drum. The movement between the driving drum and the conveyor belt depends on the friction force to drive the conveyor belt. The cargo moves with the conveyor belt on the conveyor belt. The strong belt conveyor generally uses the upper belt to transport the cargo, and it is unloaded at the end. The special unloading device can also be unloaded in the middle.
Specification type: The strong belt conveyor in our coal system use a lot, especially in recent ten years develop very fast. At present, although the strong belt conveyor is not shaped products, but the product series has been standardized.
At present, the strong belt conveyor produced in our country has 7 kinds of bandwidths, 5 kinds of belt speeds and 10 kinds of belt strength, which can form 51 kinds of different specifications of products to choose.
The bearing section and return section of the conveyor belt are supported on the frame idlers to reduce the running resistance of the conveyor belt. And the tension device provides the required tension force for the normal operation of the conveyor belt.
Compared with the general belt conveyor, the strong belt conveyor has the following characteristics:
(1) The conveyor belt of the general belt conveyor uses canvas, polyester, nylon and other fibers as the core layer of the conveyor belt; The conveyor belt of the strong belt conveyor is made of many fine steel ropes as the core layer material.
(2) Due to the limitation of the strength of the conveyor belt, the current maximum length of the general belt conveyor is generally l000 m; The conveyor belt of the strong belt conveyor adopts the silk rope as the core layer, greatly improving the strength of the conveyor belt, and the transport distance can reach 15,000 m.
(3) the general belt conveyor has shaped products, users only need to choose according to the conditions of use; Strong belt conveyor has not been finalized design products, the user needs to put forward conditions, to choose standardized design products.
The high dip Angle wavy guard conveyor belt is composed of three parts: base belt, guard edge and diaphragm. The retaining edge is used to prevent the material from slipping and scattering. In order to facilitate the bypass of the drum, the stop edge is designed to be corrugated; The role of the diaphragm is to support the material, in order to achieve large dip Angle transportation, the use of T type TC type. The baffle and the baffle are connected to the baseband by secondary vulcanization method, which has a high connection strength.
1, increase the transmission Angle (30~90 degrees);
2, small area, less investment;
3, large throughput, higher lifting height;
4. Transition from horizontal to inclined (or vertical);
5. It is suitable for conveying powdery, granular, small block, pasty and liquid materials that are easy to scatter;
6, low energy consumption, simple structure, high belt strength, long service life.
Wavy guard conveyor belt (ordinary large dip Angle wavy guard conveyor belt) varieties:
According to the different properties of the covering adhesive, the wavy retaining conveyor belt is divided into ordinary type, heat resistant type, flame resistant type, cold resistant type, acid and alkali resistant type, oil resistant type, etc.
The drum of a belt conveyor comes in two forms. One form for the electric drum, it is the motor and gear reduction device all designed in the drum, although compact structure, light volume, but not easy to install, disassembly, is not conducive to maintenance and repair, and the manufacturing process is complex, heat dissipation is difficult. Another form for the gear drum, it is the gear reduction device design in the drum, absorb the advantages of the electric drum compact structure, light volume, but it and the electric drum as the heat dissipation condition is poor, so can only be used in the low power belt conveyor. In this paper, we take the low power roller of 15kW as an example to illustrate the gear roller used for belt conveyor.
The main advantages of the gear driven drum are: reliable work, long service life, its instantaneous transmission ratio is constant, smooth work, high transmission efficiency. There are many kinds of gear drive drum, such as cylindrical gear drive, bevel gear drive, planetary gear drive, etc. As the transmission ratio of the reducer designed this time is only 12.828, and its working conditions are better, with the general ordinary gear transmission can meet the requirements. For economic consideration, we decided to use two - stage cylindrical gear drive drum.
1. Design of gear drum transmission scheme
(1) Original data
The service life of the gear drum is 10 years, 300 working days per year, 1 shift per day, 7h per shift. One year for minor repairs, three years for major repairs. The ambient temperature does not exceed 400 ° C. Its technological parameters are as follows:
Gear drum diameter (mm) : 500;
Conveyor belt width (mm) : 800;
Width of gear drum (mm) : 950;
Installation size (mm) : 1 300;
Conveyor belt running speed (m/s) : 210;
Motor power (kW) : 15;
Motor speed (r/min) : 980.
(2) Transmission scheme design
This design uses two level cylindrical gear transmission, motor output power transfer to the Ⅰ shaft, drive the Ⅰ shaft pinion 1 rotation, pinion 1 and big gear 2 meshing, at this time the power transfer to Ⅱ shaft, Ⅱ shaft drive pinion 3 and internal gear 4 meshing, so as to transfer the movement to the drum to achieve the purpose of deceleration. The whole gear drive is placed in a support frame, and a butterfly type support bar is designed to connect the inner gear 4 to the drum.
2. Determine the transmission parameters of the gear drum
Firstly, the transmission ratio of the two pairs of meshing gears should be allocated, and the following principles should be considered when allocating the transmission ratio:
① The transmission ratio of all levels of transmission should be within a reasonable range, not exceeding the maximum allowable value, in line with the transmission principle at all levels;
(2) Attention should be paid to make all levels of transmission size coordination, symmetrical and reasonable structure;
③ Try to make the outer dimension of the transmission device compact or small weight;
(4) Try to make all levels of gear oil immersion depth reasonable;
⑤ To consider the transmission parts will not interfere with the collision.
3, gear drum gear design
Pinion 1 and pinion 3 were treated with 40Cr, and the hardness was HB241 ~ HB286, with an average of HB260. Both big gear 2 and inner gear 4 were tempered with 45 steel, the hardness was HB229 ~ HB286, and the average was HB240. This design uses standard helical gear transmission, and no displacement. Gear design is considered from two aspects:
(1) The gear drum is calculated according to the contact fatigue strength of the tooth surface;
The gear drum is checked according to the bending fatigue strength of the tooth root.
Because there is no serious overload in the transmission, static strength is not checked. The modulus of the gear and the diameter of the dividing circle can be calculated, and the modulus can be rounded to determine the specific diameter of the dividing circle. When this is done, a suitable and safe gear is obtained. This design uses oil lubrication.
4. Design of gear drum shaft
The gear drum shaft is the main part in this design, so the shaft must be designed reasonably. In this design, the main design of two shafts, namely high speed shaft I and intermediate shaft II. After the preliminary design of shaft Ⅰ, we found that the shaft was not fixed firmly in the axial direction, so a sleeve and two round nuts were used to fix it to ensure the axial fixation.
After the preliminary design of the structure of the shaft, the strength of the shaft must be checked. First check the axle diameter, and then use the safety factor method to check the strength of the shaft. In the calculation of the strength of the shaft, according to the specific load and stress of the shaft, the corresponding calculation method is used, and the appropriate selection of the allowable stress. According to the structure diagram of the shaft, the calculation diagram of the shaft is made, and the bending moment diagram, torque diagram and equivalent bending moment diagram of the shaft are made according to the calculation diagram of the shaft, and then the dangerous section is determined as the middle section of the pinion. The strength of the shaft is checked according to the bending and torsion stress, usually only the section bearing the maximum calculated bending moment of the shaft is checked, and then the fatigue strength of the shaft is checked.
The above calculation shows that the design of the shaft is safe and reliable, and meets the requirements of use.
5. Selection of gear drum bearings
Because the bearing receives radial and axial loads, tapered roller bearings are selected. We choose the bearing model 7308, bearing rated dynamic load 48440N, rated static load 43540N, limit speed 5600r/min(oil lubrication), axial dynamic load coefficient 211, axial static load coefficient 112. After the initial determination of bearing type and model, we calculate and check from three aspects: (1) the calculation of life; (2) Calculation of static load; (3) Allowable speed check.
6. Structure design of other parts of gear drum
In this design, also designed a support frame and a butterfly support bar to fix the gear device in the drum.
Belt conveyors are widely used in underground roads, surface transportation systems, open-pit mines and concentrators. Used for horizontal or inclined transport. For upward sloping transport, the maximum allowable slant of different materials is β. If the beta value exceeds the specified value, due to the insufficient friction between materials and the conveyor belt, materials and materials (that is, the inclination Angle is greater than the Angle of friction), materials will slide, roll down, sprinkling, affecting the normal operation of the conveyor belt, reduce the transmission capacity. Productivity. For downward inclined transportation, the maximum allowable inclination Angle is 80% of the values listed in Table 1-1. If you need to use more than 1-1 dip conveyor, you can choose belt conveyor.
Belt conveyor is a kind of friction driven continuous material conveying machinery. It can be used to form a material transfer process between the initial feed point and the final discharge point on a conveyor line. It can not only carry out the transportation of broken materials, but also can carry out the transportation of finished products. In addition to pure material transportation, it can also meet the technical requirements of the production process of various industrial enterprises, forming a rhythmic assembly line. Therefore, belt conveyor has been widely used in modern industrial enterprises.
Belt conveyor performance is excellent: first, reliable operation. Belt conveyors are used in many important production units that require continuous operation, such as coal handling in power plants, bulk material handling in steel and cement plants, loading and unloading of ships in ports, etc. If the machine is shut down in these circumstances, the loss will be huge. When necessary, the belt conveyor can continue to work.
Belt conveyors are flexible and can receive materials from one or more points, depending on the requirements of the process flow. It can also expel material from multiple points or parts. The belt conveyor is sent to the conveyor belt at multiple points at the same time (such as the conveyor under the coal bunker in the coal preparation plant) or any point along the length direction of the belt conveyor through uniform feeding equipment to the conveyor, become the main trunk.
Large dip Angle belt conveyor is generally composed of unloading part, transmission part, driving part, brake, check, tensioning device, fuselage, deep groove roller device and tail device. The following are several typical layout structure types of strong belt conveyor.
1, large dip Angle up belt conveyor
The conveyor with high inclination Angle is 25°, which is driven by double drums and double motors. The head unloading part is composed of unloading rack, reversing drum and P and H type polyurethane cleaner. The driving part is composed of a motor, a brake, a speed-regulating coupler, a reducer and a backstop. The body is composed of deep groove roller set, longitudinal beam, leg and coal retaining device; The tensioning device adopts the tail hammer type tensioning.
2, large dip Angle on the pattern belt conveyor
The maximum transmission dip Angle of the high dip pattern belt conveyor is 30°. It adopts the single drum and double motor to drive the conveyor, and adopts the concave pattern steel rope core conveyor belt. The head unloading part is composed of the unloading rack and the reversing drum. The driving part is composed of a motor, a brake, a speed-regulating coupler, a reducer and a backstop. The body is composed of deep groove roller set, longitudinal beam, leg and coal retaining device; The tensioning device adopts the tail hammer type tensioning.
3, large dip Angle conveyor belt
The maximum transmission Angle of the belt conveyor with large dip Angle is -20°, which is driven by double drums and double motors at the tail. The head unloading part is composed of unloading rack, reversing drum and P and H type polyurethane cleaner. The driving part is composed of a motor and a reducer. The body is composed of deep groove roller set, longitudinal beam, leg and coal retaining device; Two sets of disc brakes are installed on the tail drive drum, and the tensioning device is arranged on the head of the machine. The hydraulic automatic tensioning device is used.
The use of wavy guard conveyor belt skills:
1. After purchase, do not use it directly outside, put it in a dry and ventilated place, pay attention to fire prevention and moisture-proof, especially in the finished product warehouse, can not appear Mars.
2, if the installation of wavy guard conveyor belt, must be installed in the correct order of the conveyor belt, do not install the reverse, if the reverse, will cause the double wear of the conveyor belt and conveyor, greatly reduce the service life, the material can not complete the transmission.
3. It is usually necessary to check the baffle and partition of the wavy baffle conveyor belt. Especially after long time use, the baffle and partition will become loose, especially if the baffle and partition can not be used, it must be replaced in time.
4, conveying material direction and blanking speed and conveyor belt direction and speed.
5, empty machine start, avoid motor overload, wavy guard conveyor belt skid. Remove all materials before shutdown.
6, the use of guard conveyor belt to prevent folding and hard material pressure, should be crimped use and storage.
7, the undulating guard conveyor belt tension should not be too large, should ensure that the use of tension is small.
If the undulating guard conveyor belt slips or cannot be pulled, the fault should be removed in time and the tensioning system adjusted to keep the elastic device flexible.
In the conveying process, do not make the conveyor belt run off or snake. It should be adjusted in time.
The heat-resistant conveyor belt is made of multi-layer rubber cotton canvas (TC) covered with high-temperature or heat-resistant rubber and vulcanized at high temperature.It is suitable for conveying materials such as hot coke, cement, slag and hot castings below 240 °C.
1, the specification is the same as the ordinary conveyor belt.
2. The product implements HG2297-92 and GB/T20021-2005 standards.
3. Heat-resistant conveyor belts are divided into five types:
Type I: can withstand not more than 100℃ test temperature, the highest short-time operating temperature 150℃
Type II: can withstand no more than 125℃ test temperature, the highest short-time operating temperature 170℃
Type Ⅲ : can withstand the test temperature of not more than 150℃, the highest short-time operating temperature of 200℃
Type Ⅳ : Can withstand no more than 175℃ test temperature, the highest short-time operating temperature 400℃
Type Ⅴ : can withstand not more than 240℃ test temperature, the highest short-time operating temperature 600℃
The heat resistance degree and service life of heat resistant conveyor belt mainly depend on the heat resistance performance of covering layer and core. Generally good heat resistant rubber such as: styrene butadiene rubber, butyl rubber, ethylene propylene rubber as the main rubber material, heat resistant, heat shrinkable polyester cotton, polyester canvas as core. In order to meet higher use temperature, some manufacturers have also developed heat-resistant conveyor belt with higher temperature resistance and high-temperature conveyor belt with burning resistance. Generally, flame retardant insulation agent, anti-ablative agent and thermal conductivity agent are added to the covering layer of adhesive material to improve the high-temperature and anti-ablative performance of the belt.
Mobile belt conveyor structure is light and reasonable, can be moved at any time, can be widely used in light industry and other industries in the transportation operation. In order to have a good effect in the process of use, it is necessary to install the equipment correctly. When installing the mobile belt conveyor, the following problems need to be paid attention to: pay attention to the assembly size of each part of the fuselage when installing, and keep the flatness of the whole machine. Tighten the bolts when installing bolt fasteners. When making the belt joint, align the center line of the belt at both ends to prevent the deviation of the belt. Precautions for the installation of the mobile belt conveyor. You need to pay attention to these problems when installing the components.
1) Installation of idlers
During the specific operation period of the mobile belt conveyor, the idlers play a key role. The installation quality of the idlers should be strictly mastered to ensure the normal operation of the belt conveyor, and the service life of the machinery and equipment should be increased at a certain level. During the installation of idlers, the idlers on each part should be installed first, and then the idler stands on the left and right parts should be installed, so as to promote the transmission belt to complete directional changing operation during the operation period.
In the whole process of idler installation, the installation interval should be well controlled. In general, everything is normal
Moving belt conveyor /3 ~ 1/2 is the installation interval. After the idler is installed, strict inspection is carried out on the transmission belt to ensure that the belt can rotate easily and that the idler frame has the high width ratio firmness.
2) Installation of tension device
In the whole process of the installation of the mobile belt conveyor, the effective installation of the tension device can reasonably compensate the plastic deformation and elastic deformation of the conveyor belt, to ensure that the conveyor belt to maintain sufficient support, to prevent the belt conveyor in the operation of the deviation.
When installing the tension device, check the device first to ensure that the galvanized wire rope is not broken, corrosion and other conditions, and to ensure that the conveyor belt will not be loose.
Ensure that the installation position is effective. In general, install the device in the full load supporting position close to the driving drum to ensure that the belt conveyor is not easy to run off when starting or braking system. In order to reduce tension in a greater level, as far as possible in the conveyor belt support less parts of the installation of tension devices.
3) Installation of engine support frame
The engine support frame is immediately related to whether the mobile belt conveyor can work stably. In order to give full play to all the normal characteristics of the belt conveyor reasonably, before the installation of the engine, the installation part of the support frame to carry out effective and accurate positioning, to ensure that the engine support frame part and the belt conveyor in the same parallel line, and occupy the management part, to ensure that the belt conveyor can be more stable and balanced operation.
During the actual installation of the engine support frame, the transportation spacing between each section is maintained to be the same. In addition, all the support frame sections will vertically manage the position and maintain on the same parallel line. After the engine support frame is installed, strict testing is carried out on the vertical transport inclination Angle and leveling part of the belt conveyor to ensure that the parts are in accordance with the relevant specifications and that the aspect ratio of the slope is effective.
In the installation stage, ensure that the overall axis deviation of the belt conveyor is not more than 35 mm, single and double row sound card frame matched axis to ensure that the deviation per meter is ±0. Within a millimeter.
4) Installation of driver device
The key device of the mobile belt conveyor in the specific operation period is the drive device, so as to ensure the reasonable operation of the machine equipment and fully grasp the specific installation key points of the drive device.
Mobile belt conveyor in the accelerated operation period, the drive belt is very easy to offset, so that the greater level to reduce the incidence of deviation, in the installation period to ensure the parallel surface of the reducer and rotating shaft.
After the installation of the driver device, the actual operating personnel to carry out inspection of the entire equipment, and carry out test testing, to ensure that all components of the machine and equipment are in line with the relevant specifications and requirements, and the error of the shaft of the driver device on a horizontal parallel line is within 0.5 ~ 1.5 mm.
The main differences between belt conveyor and chain plate conveyor are as follows:
First, different appearance
Two, different materials
Belt conveyor belt is generally used rubber belt, according to the characteristics of different materials can choose rubber, silicone, PVC, PU, heat resistance, cold resistance, acid and alkali resistance, oil resistance and so on. Chain conveyor generally adopts carbon steel, stainless steel, thermoplastic chain material.
3. Different application industries
The main users of belt conveyor transport bulk and finished materials, conveying material temperature is less than 60℃, coal, chemical, building materials, metallurgy, electric power, light industry, food, port and other industries.
Chain plate conveyor relies on scraper chain for conveying powder, particles and small block materials, widely used in food, chemical, pharmaceutical, building materials, metallurgy, coal and other industries.
Four, the throughput is different
Belt conveyor conveying distance can reach 203 meters, the conveying capacity range between 30~3000 tons/hour, chain plate conveyor conveying capacity can reach 80~240 cubic meters/hour, can be horizontal, inclined, vertical conveying distance as long as 40~90 meters.
Five, the working principle is different
The belt conveyor is a conveying machine that bypasses the head and tail drums to form a closed loop. It transmits power through the friction between the driving drum and the conveyor belt to realize material conveying. Can be used for horizontal, tilt up, tilt down conveying materials.
Chain plate conveyor uses a series of chains fixed on the traction chain to supply traction, and uses metal plates as carriers to lead materials to be transported in a horizontal or skewed direction.
The above is the difference between the belt conveyor and the chain conveyor, the belt conveyor is suitable for light transport, low noise, low cost, chain conveyor is suitable for heavy transport, long life.
1. The motor cannot start or slows down immediately after starting
The reasons for this phenomenon are mainly manifested in the following aspects: (1) line fault; ② Protect electronic control system lock; ③ Contactor failure; ④ The voltage drops.
In this case, the line should be checked in time to check the deviation, limit, stop along the line and other protection. Check the voltage, check the overload relay.
2 Motor heating
Due to overload, excessive length or the conveyor belt is blocked, the operation resistance increases, the motor is overloaded, the lubrication condition of the transmission system is poor, and the motor power increases. Secondly, dust accumulates in the motor fan inlet or radial gasket, which worsens the heat dissipation conditions. The solution is: find out the cause of overload operation; Timely supplementary lubrication of each transmission part; Remove dust.
3. Conveyor belt deviation
① Installation quality problems. The frame and drum are not adjusted straight, and the line of the supporting roller is not perpendicular to the center line of the conveyor belt. At this time, the frame or roller should be adjusted to keep it straight.
(2) Conveyor belt quality problems. The conveyor belt joint is not vertical to the center, and the conveyor belt edge is Z-shaped. It should be re-made to ensure that the joint is vertical to the center line of the conveyor belt, cut off the not straight part and redo the joint.
③ Loading quality problem. The loading point is not in the center of the conveyor belt (off-load). The blanking point should be adjusted.
4. Aging and tearing problem of conveyor belt
The conveyor belt and the frame friction, producing belt edge hair, cracking. Should be adjusted in time to avoid long-term deviation of the conveyor belt. The conveyor belt interferes with a fixed hard object to tear. Prevent the conveyor belt from swinging onto fixed members or falling into metal members in the conveyor belt. The tension force is too large, the laying is too short, and the number of flexure exceeds the limit value, resulting in premature aging.
5 Broken tape
The material of belt body is not suitable for water and cold. The core should be made of materials with stable mechanical and physical properties. The conveyor belt is used for a long time, the strength becomes worse, and the damaged or aging conveyor belt must be replaced in time. Always observe the joint and deal with the problem in time.
6 Roller does not turn
(1) The roller does not contact the conveyor belt. The position of the roller should be raised so that it is in contact with the conveying.
The shell of the roller is blocked by the material, or the end face of the roller interferes with the support of the roller. At this time, it is necessary to remove the material, add a washer or correct the roller support at the interference part, so that the end face is out of contact.
(3) The roller seal is not good, so that the coal powder into the bearing and cause the bearing jam. The roller should be disassembled and cleaned in time.
7 Skid problem
The belt tension force is insufficient, the load is too large to cause the belt slip, should be readjustedthe tension force, reduce the volume of transport. Secondly, the friction coefficient between the drum and the conveyor belt is reduced because of the water. At this time, the water should be eliminated, the tensioning force should be increased, and the rubber pattern roller should be used.
Belt conveyor is a continuous transport machine with flexible tractive components. Due to its large transportation capacity, running resistance, low power consumption, stable operation, small crushing of materials in operation, continuous operation easy to realize automatic control. Therefore, it is widely used in various sectors of national economy. But in the process of use, there are also many problems. It is necessary to master reasonable operation methods and adjust all links in time to avoid the above faults, so as to ensure that the belt conveyor plays its role in application.