Firstly, a bundle puller is usually composed of a main frame welded from steel structure, a lead screw, an electric control cabinet, a cycloidal pinwheel reducer, a motor, a heavy-duty trolley, control switches, nuts, a lifting crossbeam, and a bearing seat. During operation, the core extractor is lifted by a crane and placed in front of the heat exchanger. Its working principle is to use a planetary cycloidal pinwheel reducer as the power source and a trapezoidal lead screw for transmission, which has the characteristics of high pulling force, stable core extraction, time saving, labor saving, and no damage to the heat exchanger core.
In the operation process, the operation of the extractor is relatively simple. For example, gear oil is added to the gearbox of the reducer, and the new oil needs to be replaced after the first 160 hours of operation, and the bearing grease is replaced at least once a year. When using, use a jack to top the core of the extractor, and push the tailstock of the extractor tightly against the flange end face of the heat exchanger shell. Drill the flange holes of the shell to fix the tailstock and the heat exchanger shell with bolts. Wrap the heat exchanger core with a wire rope, and connect the other end to the nut for fixation. After checking, start the motor to work. The two heavy-duty trolleys are placed not close to the core end, and the first heavy-duty trolley near the nut should be appropriately higher than the other heavy-duty trolley. When the core is pulled out, it contacts the first heavy-duty trolley, and when it is pulled out to a certain distance, the core naturally falls onto the other heavy-duty trolley until the core is completely pulled out.
The technical performance of the bundle puller also has certain characteristics. For example, the maximum length of the extracted tube bundle is 6000mm, the diameter range of the extracted tube bundle is 400-1400mm, the maximum weight of the extracted tube bundle is 30 tons, the flange thickness of the heat exchanger shell allowed for extraction does not exceed 250mm, and the thickness of the tube plate of the heat exchanger tube bundle allowed for extraction does not exceed 250mm. The type of tube bundle extraction is upper support, and the operation mode is manual + remote control. The external dimensions are not less than 9500 × 1650 × 1500mm, the self-weight is not more than 5.4 tons, the power supply voltage is 380V three-phase 50HZ, and the protection level of electrical components is IP54. The extraction speed is 1600-1800mm/min. The frame is composed of side beams and bottom beams welded together, with lifting lugs on both sides of the side beams, and hydraulic pipelines and electrical control lines installed in the inner cavity of the guide rail; the bottom beam adopts a hollow structure, one of which is used as the hydraulic pipeline leading from the hydraulic oil cavity and is connected to the hydraulic cylinder; the inner cavity of the other bottom beam is equipped with an electrical controller, the maximum load-carrying capacity of the frame is 30 tons, the straightness of the frame guide rail is less than 0.2mm for a length of 1000mm, and the frame material is Q235B. The transmission system consists of a traction motor, a worm gear reducer, a drive sprocket, and a drive chain, and the output shaft of the worm gear reducer drives the sprocket to rotate.
What are the components of a bundle puller?
A bundle puller mainly consists of the following parts:
· Frame: Usually composed of side beams and bottom beams welded together, with lifting lugs on both sides of the side beams, and hydraulic pipelines and electrical control lines installed in the inner cavity of the guide rail. The bottom beam adopts a hollow structure, one of which is used as the hydraulic pipeline leading from the hydraulic oil cavity and is connected to the hydraulic cylinder; the inner cavity of the other bottom beam is equipped with an electrical controller. The maximum load-carrying capacity of the frame can reach 30 tons, and the straightness of the guide rail is required to be high, with a length of 1000mm less than 0.2mm, and the material is generally Q235B.
· Main traveling crane: The main traveling crane is also equipped with a pushing device, and a pushing device is installed on the main plate of the main traveling crane, and a driving device and its connecting rod are installed under the main plate of the main traveling crane. The main traveling crane moves on the guide rail of the frame and is driven by a chain to complete the extraction and installation of the tube bundle.
· Small traveling crane: It is placed on the guide rail of the frame and used in conjunction with the main traveling crane.
· Clamping foot: It is set at the front end of the guide rail for clamping the tube bundle.
· Power mechanism and transmission mechanism: The transmission system consists of a traction motor, a worm gear reducer, a drive sprocket, and a drive chain, and the output shaft of the worm gear reducer drives the sprocket to rotate to provide power for the equipment.
· Clamping mechanism: It includes a lifting plate, a supporting plate, a clamping plate, a mounting seat, a telescopic rod, a limit plate, etc. The top of the supporting plate is connected to an arc-shaped pad through a spring, and one end of the limit plate away from the car body is connected to a clamping block, and the side in contact with the end plate of the tube bundle is connected to a rubber pad. The lifting member includes a pneumatic telescopic rod installed in the car body, etc.
· Oil tank body and return oil tank: An L-shaped integral hydraulic oil tank for easy installation of the bundle puller, including an oil tank body and a return oil tank located on one side of the oil tank body, the return oil tank communicates with the oil tank body, and the upper end of the oil tank body is provided with an oil pipe cover, on which an oil pipe and a return pipe are installed, and the oil pipe and the return pipe communicate with the inner cavity of the oil tank body. On one side of the oil tank body, a filter pipe interface and a positioning mechanism are provided above the return oil tank, and a respirator filler cap is assembled in the filter pipe interface, and the respirator filler cap is screwed to the filter pipe interface.
What is the working principle of a bundle puller?
The working principle of a bundle puller mainly realizes the extraction and installation of the heat exchanger tube bundle through the coordinated action of various components. Firstly, the equipment is placed in the appropriate position, and the power supply and steel cables are connected. During the operation, the main traveling crane is driven by the chain to move on the guide rail of the frame, and the pushing device and clamping foot on the main traveling crane cooperate to clamp and pull the tube bundle. For example, when disassembling the tube bundle, first lift the core extractor to the vicinity of the tube bundle, press the clamping and loosening button to extend the clamping cylinder to an appropriate position (exceeding the flange thickness of the heat exchanger shell). Then press the left and right side lowering buttons, and after the left and right balance cylinders extend, connect the steel cable at the front end of the cylinder piston rod to the flange of the heat exchanger shell with bolts. Next, press the left and right side lifting buttons, and the piston rods of the left and right cylinders retract and tighten the steel cable. At the same time, through the joint adjustment of the crane, make the jaw of the core extractor butt against the flange of the heat exchanger shell, and make the height of the core extractor suitable, and the axis is consistent with the heat exchanger. Press the clamping and tightening button to make the core extractor and the flange of the heat exchanger shell tightly pressed together, and then drive the traveling crane to the foremost position. Assemble the primary tension beam and connect it to the rear of the tube bundle through the primary tension cable. Press the traveling crane return button, and the traveling crane will drag the tube bundle out through the primary tension beam. During the process of tube bundle extraction and installation, the hydraulic system provides power, and different operation steps are realized by controlling the expansion and contraction of each cylinder. At the same time, the manual, remote control, and wire control three sets of control systems of the equipment ensure the safety of the operator and are very flexible and convenient to use.
What is the technical performance of a bundle puller?
A bundle puller has the following technical performance:
· Overall performance: The maximum length of the extracted tube bundle can reach 6000mm, the diameter range of the extracted tube bundle is 400-1400mm, the maximum weight of the extracted tube bundle is 30 tons, the flange thickness of the heat exchanger shell allowed for extraction does not exceed 250mm, and the thickness of the tube plate of the heat exchanger tube bundle allowed for extraction does not exceed 250mm. The type of tube bundle extraction is upper support, and the operation mode is manual + remote control. The external dimensions are not less than 9500 × 1650 × 1500mm, the self-weight is not more than 5.4 tons, the power supply voltage is 380V three-phase 50HZ, and the protection level of electrical components is IP54. The extraction speed is 1600-1800mm/min.
· Good safety and high structural strength. It has been checked and verified for structural strength by the Department of Structural Mechanics of Dalian University of Technology, and at the same time, the structural design has been optimized to ensure the strength requirements and minimize the self-weight as much as possible.
· Simple and practical operation, which can greatly reduce the labor intensity of field workers and improve labor efficiency. High applicability, one extractor can meet the extraction and installation requirements of various types of heat exchanger tube bundles.
· Hydraulic connection and adjustment, the connection and adjustment process is reliable and easy to operate. Chain dragging, strong power. Stable and fast extraction and installation.
· Low failure rate and good maintainability. In the design, the harsh field environment and the inevitable strong collision in use are fully considered, and the vulnerable parts are reliably protected and isolated from pollution. Therefore, the failure rate of this machine is extremely low. All parts of this machine are standard parts, and even if they are damaged, they can be easily purchased.
What is the operating process of a bundle puller?
The operating process of a bundle puller is as follows:
· Pre-operation inspection: Inspect and remove foreign objects on the chain, clean foreign objects on the main slideway, connect the steel cables of each part, and if the diameter of the extracted tube bundle is φ1800, a bracket should be installed.
· Startup: In manual operation, the (manual/remote) switch in the control cabinet is placed in the manual position, and manual operation can be performed. In remote control operation, insert the battery, turn on the power switch of the remote control, and unscrew the international standard “press in/rotate out” button.
· Operation steps:
· Initial position: The traveling crane is in the middle position of the equipment, the lead screw is in the extended position of 10mm, and the hanging plate is in the 45-degree position.
· Disassembling the tube bundle (remote control operation): Lift the core extractor and lift it to the vicinity of the tube bundle. Press the clamping and loosening button to extend the clamping cylinder to an appropriate position (exceeding the flange thickness of the heat exchanger shell). Press the left and right side lowering buttons, and after the left and right balance cylinders extend, connect the steel cable at the front end of the cylinder piston rod to the flange of the heat exchanger shell with bolts. Press the left and right side lifting buttons, and the piston rods of the left and right cylinders retract and tighten the steel cable. At the same time, through the joint adjustment of the crane, make the jaw of the core extractor butt against the flange of the heat exchanger shell, and make the height of the core extractor suitable, and the axis is consistent with the heat exchanger. Press the clamping and tightening button to make the core extractor and the flange of the heat exchanger shell tightly pressed together, and then drive the traveling crane to the foremost position. Assemble the primary tension beam and connect it to the rear of the tube bundle through the primary tension cable. Press the traveling crane return button, and the traveling crane will drag the tube bundle out through the primary tension beam. Remove the primary tension beam and primary tension cable, and use the secondary tension cable to tie the flange of the tube bundle. Press the traveling crane return button, and the tube bundle will be dragged out. When the tube bundle is dragged out to the position where the hanging plate on the traveling crane can be hung on the flange of the tube bundle, remove the towing cable and move the traveling crane forward to the position where the hanging plate can be hung on the flange of the tube bundle.
· Precautions: The extractor should be placed in a flat place on the ground and protected from rain. Select a steel cable for hoisting the extractor that matches the hoisting load. When starting and stopping the machine, confirm the initial position set by the extractor. It is strictly prohibited to set up a temporary power supply in places with explosion and fire hazards, and the capacity of the power supply should match the power of the extractor. The extractor does not have explosion-proof function and should have a good ground wire. Confirm that there is no remote control with the same frequency within 100m around to prevent interference. The output force of the lead screw of the extractor is only 3000kg, and the tube bundle cannot be pushed in alone, only with the traveling crane to push the tube bundle into the heat exchanger completely. When operating at a height of more than 2 meters, the operator should wear a safety belt. In the process of disassembling or reinstalling the tube bundle, if there is a blockage, stop the operation immediately, and after inspection and adjustment, resume the disassembly or extraction and installation, and never force the tube bundle. The handle of the primary tension beam can only bear its own weight, and the steel cable should be hung on the main body of the primary tension beam, not on the handles at both ends of the primary tension beam, otherwise, the handle may be broken.
A bundle puller is a professional equipment used for the extraction and installation of heat exchanger tube bundles. Its components are complex, and through the coordination of various components, under the guidance of the working principle, it shows good technical performance. Different types and brands of bundle pullers have their own characteristics in the market to meet the needs of different users. During the operation, the operation process is strictly followed, and safety matters are noted to ensure the normal operation of the equipment and the safety of the operators.
