The performance of bundle puller varies in different working conditions. Firstly, in terms of the working environment, factors such as temperature, pressure, and humidity can affect its working performance and adaptability. For example, in some special working conditions, features such as remote control operation and explosion-proof function may be required.
Secondly, in terms of the equipment structure and composition, bundle puller mainly consists of a frame, a main traveling mechanism, a small traveling mechanism, clamping feet, a power mechanism, and a transmission mechanism. The frame is the basic structure of the equipment, welded by side beams and bottom beams. The side beams on both sides are equipped with lifting lugs, and the inner cavity of the guide rail is equipped with hydraulic pipelines and electrical control lines. The bottom beam adopts a hollow structure, one of the bottom beams is used as the hydraulic pipeline extending from the hydraulic oil cavity and is connected to the hydraulic cylinder. / The bottom beam adopts a hollow structure, one of the bottom beams is used as the hydraulic pipeline led out from the hydraulic oil cavity and is connected to the hydraulic cylinder., and the other bottom beam inner cavity 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 requires a high level, less than 0.2mm in 1000mm length, and the material is generally Q235B. The main traveling mechanism is also equipped with a pushing device, which can play an important role in the process of extracting and installing the bundle. The transmission system consists of a traction motor, a worm gear reducer, a drive sprocket, and a drive chain. The output shaft of the worm gear reducer drives the sprocket to rotate, and the traction force drives the main traveling mechanism to move back and forth along the guide rail of the frame through the chain to achieve the extraction and installation of the bundle. The small traveling mechanism also plays an auxiliary role in the equipment, for example, in the process of pushing the bundle back, due to the existence of the small traveling mechanism, the main traveling mechanism cannot completely push the bundle back into the heat exchanger shell, and at this time, other devices may be required to cooperate to complete the operation. The clamping feet are set at one end of the guide rail to fix the position of the equipment. The power mechanism provides a power source for the equipment, usually including equipment such as motors. In addition, the equipment may also include components such as a take-up device and a hanging plate device. The take-up device can be used to receive the bundle and adjust its position. The hanging plate device is equipped with a hanging plate, a lifting hanging plate, and a vertical connecting hanging plate, an inclined plate of the lifting hanging plate to form a clamping part for clamping the tube plate of the bundle, and an adjustment mechanism is also provided to adjust the height of the entire hanging plate device.
The role of bundle puller in different heat exchangers
Bundle puller plays an important role in different types of heat exchangers. For example, in a floating head heat exchanger, because its bundle can be pulled out for cleaning, it can be used in occasions where scaling is likely to occur or the tube side is prone to corrosion. However, the floating head heat exchanger has a complex structure, and the small floating head is prone to internal leakage, and the consumption of metal materials is large, and the cost is higher than that of ordinary heat exchangers. In a shell and tube heat exchanger, although the cost is cheap and the structure is simple and compact, the bundle cannot be cleaned, and there is a large temperature difference stress between the tube wall and the shell wall. For a U-tube heat exchanger, its advantages are that the bundle can expand and contract freely, there is no thermal stress between the tube and the shell, the tube side is a double-tube side, the process is long, the heat exchange effect is good, the pressure resistance is strong, the structure is simple, the cost is cheap, and the bundle can be pulled out from the inside of the shell for easy maintenance. However, the tube cannot be cleaned inside, and the tubes in the middle of the bundle are difficult to replace. The tubes are not distributed compactly, and the shell-side fluid is prone to short circuit, resulting in inconvenient heat exchange, and the tubes are prone to bending, and the use place is limited. In an immersed snake heat exchanger, the structure is simple, easy to install and maintain, and corrosion resistant, with high pressure resistance, but the equipment is bulky and consumes a lot of materials. In a spray-type snake tube heat exchanger, the heat exchange efficiency is better than that of the immersed type, the heat transfer area is large, and it is convenient for maintenance and cleaning, but the spray is not uniform, and it is often used for cooling the fluid in the tube, and is mostly installed in outdoor air circulation places. In short, bundle puller can meet the extraction and installation requirements of different types of heat exchanger bundles, providing an important guarantee for the maintenance and repair of heat exchangers.
The operation process of bundle puller
The operation process of bundle puller is relatively complex and requires strict adherence to the operating procedures. Firstly, a series of preparatory work needs to be done before operation, such as checking and removing foreign objects on the chain, cleaning foreign objects on the main slide, and connecting the cables of various parts. If the diameter of the bundle to be extracted is within a certain value, a bracket should be installed. In terms of power connection, the power supply is 380V ± 10%, and the power of different models of extractors varies. When starting the machine, manual or remote control operation can be selected. Manual operation is to put the selector switch in the control cabinet in the manual position. Remote control operation requires installing a battery, turning on the power switch of the remote control, and unscrewing the international standard “press in / unscrew” button. When disassembling the bundle, remote control operation can be used. First, lift the core extractor and hoist it near the bundle. Press the clamping and loosening button to extend the clamping cylinder to the appropriate position, which exceeds the thickness of the heat exchanger shell flange. Then press the left and right 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 heat exchanger shell flange with bolts. Then press the left and right rising buttons, and the piston rods of the left and right cylinders retract and tension the steel cable. At the same time, through the combined adjustment of the crane, make the jaw of the core extractor butted with the heat exchanger flange, and make the height of the core extractor suitable, and the axis is consistent with the heat exchanger. Press the clamping button to tightly press the core extractor and the heat exchanger flange together, and then drive the traveling mechanism to the frontmost position. Assemble the initial tension beam and connect it to the rear of the bundle through the initial tension cable. Press the traveling mechanism retract button, and the traveling mechanism will drag the bundle out. The distance dragged out should be as large as possible. Remove the initial tension beam and the initial tension cable, and use the secondary tension cable to bind the flange of the bundle. Press the traveling mechanism retract button, and the bundle is dragged out. When the bundle is dragged out to the position where the hanging plate on the traveling mechanism can be hooked to the flange of the bundle, remove the towing cable and move the traveling mechanism forward to the position where the hanging plate can hook the flange of the bundle. During the operation, if there is a jam, stop the operation immediately. After inspection and adjustment, re-start the disassembly or extraction, and never forcefully load or unload the bundle.
The safety protection device of bundle puller
The safety protection device of bundle puller is an important component to ensure the safety of operators. Safety protection devices include safety doors, limit switches, safety valves, etc. By monitoring the movements of the hydraulic system and the tube bundle extractor, the safety of operators is guaranteed. For example, during the operation, if there is an abnormal situation with the equipment, the safety protection device can stop the equipment in time to avoid accidents. At the same time, when operating at a height of more than 2 meters, the operator should wear a safety belt, and the extractor should be placed in a flat place on the ground and protected from rain. The steel cable selected for hoisting the extractor should match the hoisting load, and it is strictly prohibited to set up a temporary power supply in places with explosion and fire hazards. The extractor does not have explosion-proof function and should have a good ground wire. Within a 100m radius, the same frequency remote control should be confirmed to prevent interference. The output force of the extractor’s top-in screw is only 3000kg, and it cannot push the bundle into the heat exchanger alone, only in conjunction with the traveling mechanism to push the entire bundle into the heat exchanger. The handle of the initial tension beam can only bear its own weight, and the steel cable should be hung on the main body of the initial tension beam, not on the handles at both ends of the initial tension beam, otherwise, the handle may be broken.
To sum up, the performance of bundle puller in different working conditions is affected by many factors. Environmental factors such as temperature, humidity, and pressure can have varying degrees of impact on the performance of the equipment. The structure and composition of the equipment determine its role in different heat exchangers and the operation process. During the operation, strictly follow the operating procedures and rely on safety protection devices to ensure the safety of operators, which can improve the performance and working efficiency of bundle puller, and provide a strong guarantee for the maintenance and repair of heat exchangers.
