Tube head aligning device of shell-and-tube heat exchanger

Abstract

The utility model discloses a tube head aligning device of a shell-and-tube heat exchanger, comprising a split shaft, the front part of which is enclosed by two halves, and the rear part of which is a complete circumference and is provided with an external thread; the sliding block is located in the front inner cavity of the split shaft and can float in the radial direction; the hard alloy wheel is fixed on the support lug of the sliding block through a wheel shaft, and the blade point of the wheel flange can protrude out of the circular seam of the subdivision shaft; one end of the lever is inserted into the bottom of the sliding block, and the other end of the lever extends out of the axial long groove of the subdivision shaft; the thread feeding sleeve is sleeved on the periphery of the middle section of the split shaft, a middle large-diameter section forms a cavity for accommodating the lever, a front reducing section is sleeved on the periphery of the split section of the split shaft, and a rear reducing section is screwed with an external thread of the split shaft through an internal thread; and the two rotation stopping rods symmetrically penetrate through the axial through hole of the thread feeding sleeve. According to the device, accurate positioning can be achieved when the pipe head is cut, and safety is good.

Description

Technical Field

[0001] The utility model relates to a shell and tube heat exchanger, in particular to a device for aligning tube heads of a shell and tube heat exchanger, belonging to the technical field of welding auxiliary tools. Background Art

[0002] Both ends of each tube in the shell and tube heat exchanger are respectively inserted into the mounting holes of the tube sheet 18, and the tube heads extend out of the mounting holes. During the manufacturing process of the shell and tube heat exchanger, in order to keep the lengths of the heat exchange tubes extending out of the tube sheet consistent, the redundant parts need to be removed, and this process is called aligning tube heads.

[0003] At present, the method for aligning tube heads is to use a rotating milling cutter to mill a certain length from the end face of the heat exchange tube towards the tube sheet.

[0004] Milling the tube heads requires a certain pressure applied by the operator, which will also cause a certain load on the precise positioning device, resulting in inaccurate positioning or even directly damaging the positioning device. Due to the inability of the existing tools to accurately position, the milling depth can only depend on the operator's feeling, and it is difficult to make the lengths of the tube heads consistent after milling. As a result, the lengths of some tube heads extending out are significantly lower than the requirements of the drawing, and even the tube sheet is milled, affecting the product quality.

[0005] In addition, since the milling position is too close to the surface of the tube sheet, using methods such as baffles for protection will affect the operator's vision and interfere with the operation. Only methods such as the operator wearing goggles and protective masks can be used, and there is still a risk of the rotating milling cutter and the iron chips thrown out by the milling cutter hurting the surrounding personnel during the working process. Summary of the Utility Model

[0006] The purpose of this part is to outline some aspects of the embodiments of the utility model and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this part as well as in the abstract and the title of the specification of this application, but such simplifications or omissions shall not be used to limit the scope of the utility model.

[0007] In view of the above and / or existing problems, the present utility model is proposed.

[0008] The purpose of the utility model is to overcome the problem that the lengths of the heat exchange tubes extending out of the tube sheet are inconsistent after the operation in the prior art, and to provide a device for aligning tube heads of a shell and tube heat exchanger, which can achieve precise positioning when cutting the tube heads, ensure that all the tube heads extending out of the tube sheet are flush, and has good safety.

[0009] To solve the above technical problems, a device for aligning tube heads of a shell and tube heat exchanger of the utility model includes:

[0010] A split shaft, the front part of which is formed by enclosing two halves, and the rear part is a complete circumference and is provided with an external thread;

[0011] The slider is located in the front inner cavity of the split shaft and can float radially.

[0012] The cemented carbide wheel is fixed to the lug of the slider through a wheel shaft, and the cutting edge of the wheel rim can protrude from the annular gap of the split shaft.

[0013] The lever is located in the front inner cavity of the split shaft, with the middle as the hinge fulcrum. One end is inserted into the bottom of the slider, and the other end extends out from the axial long slot of the split shaft.

[0014] The threaded feed sleeve is sleeved on the outer periphery of the middle section of the split shaft. The large-diameter section in the middle forms a cavity for accommodating the lever. The front reduced-diameter section is sleeved on the outer periphery of the split section of the split shaft, and the rear reduced-diameter section is screwed with the external thread of the split shaft through an internal thread.

[0015] There are two anti-rotation rods, which symmetrically pass through the axial through holes of the threaded feed sleeve.

[0016] As an improvement of the present invention, a return spring is supported between the top surface of the slider and the inner wall of the split shaft.

[0017] As a further improvement of the present invention, sliding block grooves are respectively provided on the front and rear sides of the slider, and the two sliding block grooves are respectively embedded on the vertical rib plates of the inner wall of the split shaft.

[0018] As a further improvement of the present invention, a bushing is provided in the central hole of the cemented carbide wheel.

[0019] As a further improvement of the present invention, the front end of the split shaft is provided with a reduced-diameter outer step of the split shaft. A lock sleeve is sleeved on the outer step of the split shaft. The front end of the lock sleeve is provided with a reduced-diameter section of the lock sleeve. A bearing is sleeved on the reduced-diameter section of the lock sleeve. The outer ring of the bearing is in contact with the inner wall of the heat exchange tube. The front end of the inner ring of the bearing is pressed with a locking head, and the central screw of the locking head is screwed into the front screw hole of the lock sleeve.

[0020] As a further improvement of the present invention, the rear end head of the split shaft is fixedly connected to the front end of the drive shaft. The rear end of the drive shaft is connected to the output end of the speed reduction mechanism. The input end of the speed reduction mechanism is connected to the output shaft of the motor. The middle section of the drive shaft passes through the central hole of the hollow stud. The hollow stud is fixed on the front end face of the speed reduction mechanism.

[0021] As a further improvement of the present invention, the rear end of the anti-rotation rod is connected to the front end face of the hollow stud.

[0022] As a further improvement of the present invention, a three-jaw assembly is screwed on the hollow stud, and the three jaws of the three-jaw assembly are flush at the front end and abut against the tube sheet.

[0023] Compared with the prior art, the utility model has achieved the following beneficial effects: 1. There is no need to apply pressure to the tube sheet, and various precise positioning means can be adopted without considering the load or damage to the positioning device.

[0024] 2. During the operation of this device, no flying metal chips are generated, and there is no sharp cutter head. Theoretically, it is impossible to hurt human skin, which can completely solve the safety problems caused by the rotating milling cutter and flying metal chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings. The drawings are only for reference and explanation, and are not used to limit the present utility model. Among them:

[0026] Figure 1 is the front view of the tube head device of the shell-and-tube heat exchanger of the present utility model;

[0027] Figure 2 is Figure 1 the top view of;

[0028] Figure 3 is Figure 1 the perspective view of;

[0029] Figure 4 is Figure 1 the exploded view of;

[0030] Figure 5 is Figure 4 the partial enlarged view in;

[0031] Figure 6 is the partial enlarged view of the cutting part in the present utility model;

[0032] Figure 7 is the cross-sectional view of the front half part of the present utility model;

[0033] Figure 8 is Figure 7 the partial enlarged view in;

[0034] In the figure: 1. Locking head; 2. Bearing; 3. Locking sleeve; 4. Split shaft; 4a. First half shaft; 4b. Second half shaft; 4c. Lever pin shaft; 4d. Axial long slot; 4e. Split shaft circumferential seam; 4f. Spring positioning post; 4g. Half shaft screw; 5. Return spring; 6. Wheel shaft; 7. Slide block; 8. Bushing; 9. Cemented carbide wheel; 10. Lever; 11. Fork head bolt; 12. Three-jaw assembly; 12a. Inner jaw; 12b. Middle jaw; 12c. Outer jaw; 12d. Three-jaw gland; 13. Threaded feed sleeve; 14. Anti-rotation rod; 15. Motor; 16. Drive shaft; 17. Hollow stud; 18. Tube sheet; 19. Heat exchange tube. Detailed implementation manner

[0035] In the following description of the present invention, the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating that the device must have a specific orientation.

[0036] In order to make the technical means, creative features, achieved purposes and functions implemented by the present invention easy to understand, the present invention will be further described below with reference to specific drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments, and are not intended to limit the present invention.

[0038] As Figures 1 to 8 shown, the tube head device of the shell-and-tube heat exchanger of the present invention includes a locking head 1, a bearing 2, a locking sleeve 3, a first half shaft 4a, a second half shaft 4b, a return spring 5, a slide block 7, a cemented carbide wheel 9, a lever 10, a three-jaw assembly 12 and a motor assembly. The split shaft 4 is formed by the first half shaft 4a and the second half shaft 4b enclosing each other. The rear part of the first half shaft 4a is a complete circumference and is provided with an external thread. The front part of the first half shaft 4a and the second half shaft 4b enclose a complete circumference, that is, the front part of the split shaft 4 is a split structure, and the rear threaded section is a complete structure. Multiple half shaft screws 4g fixedly connect the second half shaft 4b and the first half shaft 4a.

[0039] The inner cavity of the split shaft 4 is provided with a reset spring 5, a slider 7, a carbide wheel 9 and a lever 10. The middle of the bottom plate of the slider 7 is provided with slider grooves on both sides, and the two slider grooves are respectively embedded in the vertical ribs on the inner wall of the first semi-shaft 4a and the second semi-shaft 4b so that the slider 7 can only float along the radial direction of the split shaft 4. A pair of parallel slider ears are welded at one end of the slider bottom plate. A bushing 8 is provided in the center hole of the carbide wheel 9, which is supported in the middle of the wheel shaft 6 through the bushing 8 to reduce the rolling resistance of the carbide wheel 9. The carbide wheel 9 is located between the two slider ears, and the wheel shaft 6 passes through the through hole at the top of the slider ears, and the end threaded section is fixed with a wheel shaft nut.

[0040] The other end of the slider bottom plate is provided with a return spring 5 for pushing the slider 7 to sink, and the fixed end of the return spring 5 is sleeved on the outer periphery of the spring positioning column 4f, and the spring positioning column 4f is connected to the inner wall of the first semi-axis 4a as a whole.

[0041] One end of the lever 10 is a resistance arm inserted under the bottom plate of the slider on the side where the carbide wheel 9 is located. The middle part of the lever 10 is hinged in the first half shaft 4a through the lever pin 4c. The root of the lever pin 4c is connected to the inner wall of the first half shaft 4a as a whole. A screw hole is provided at one end of the lever pin 4c facing the second half shaft 4b for the half shaft screw 4g to be screwed and fixed.

[0042] The other end of the lever 10 is a power arm that tilts upward and extends from an axial long groove 4d surrounded by the first semi-axis 4a and the second semi-axis 4b. The axial long groove 4d occupies half of the facing end surfaces of the first semi-axis 4a and the second semi-axis 4b.

[0043] The first half shaft 4a and the second half shaft 4b are also provided with a split shaft ring gap 4e for the wheel rim blade of the hard alloy wheel 9 to extend out.

[0044] The front end of the first semi-shaft 4a and the second semi-shaft 4b enclosed together forms a reduced diameter outer step of the split shaft, and the locking sleeve 3 is mounted on the outer step of the split shaft to lock and fix the first semi-shaft 4a and the second semi-shaft 4b. The front end of the locking sleeve 3 is provided with a locking sleeve reduced diameter section, and the locking sleeve reduced diameter section is mounted with a bearing 2. The front end center hole of the locking sleeve 3 is provided with an internal thread, and the screw of the locking head 1 is screwed into the screw hole of the locking sleeve 3. The inner end face of the locking head 1 is against the inner ring of the bearing 2 to press it against the outer step of the locking sleeve 3. The outer end face of the locking head 1 is provided with a radial wrench to facilitate tightening the locking head 1.

[0045] The outer ring of the bearing 2 fits against the inner wall of the heat exchange tube 19 to play a centering role, preventing the part extending into the heat exchange tube 19 from damaging the inner wall of the heat exchange tube due to the jumping caused by the rotation.

[0046] The slider 7 is tilted up by the lever 10 , so that the carbide wheel 9 floats radially outward until the wheel rim protrudes from the split shaft ring seam 4 e and cuts the inner wall of the heat exchange tube 19 .

[0047] A threaded feed sleeve 13 is sleeved on the outer periphery of the middle part of the split shaft 4. Feed sleeve reduced-diameter sections are respectively provided at both ends of the threaded feed sleeve 13. The inner feed sleeve reduced-diameter section close to the cemented carbide wheel 9 is a smooth hole sleeved on the outer periphery of the split sections of the first half shaft 4a and the second half shaft 4b, and the outer feed sleeve reduced-diameter section close to the motor assembly is a threaded hole and is screwed on the outer periphery of the first half shaft 4a.

[0048] The power arm of the lever 10 extends out from the axial long groove 4d at the front part of the split shaft 4 and is located in the inner cavity of the large-diameter section in the middle of the threaded feed sleeve 13. When the split shaft 4 rotates to move the threaded feed sleeve 13 outward along the axis of the split shaft 4, the inner feed sleeve reduced-diameter section of the threaded feed sleeve 13 presses on the power arm of the lever 10. As the threaded feed sleeve 13 moves outward, the power arm of the lever 10 is gradually pressed down. The lever 10 rotates around the lever pin shaft 4c, and the resistance arm of the lever 10 tilts upward, causing the slider 7 and the cemented carbide wheel 9 to float radially outward. In this way, the lever 10 converts the axial movement of the threaded feed sleeve 13 into the radial movement of the cemented carbide wheel 9 until the blade edge of the wheel rim of the cemented carbide wheel 9 protrudes from the split shaft annular gap 4e.

[0049] The motor assembly includes a motor 15, a drive shaft 16 and a hollow stud 17. The drive shaft 16 passes through the central hole of the hollow stud 17 and is connected to the outer end of the first half shaft 4a. A fork head is provided at the outer end of the first half shaft 4a and is fixedly connected to the fork head of the drive shaft 16 through a fork head bolt 11. The drive shaft 16 is driven by the motor 15 through a reduction mechanism, and the hollow stud 17 is fixed on the front end face of the reduction mechanism.

[0050] A three-jaw assembly 12 is screwed in the hollow stud 17. The three-jaw assembly 12 includes an inner jaw 12a, a middle jaw 12b, an outer jaw 12c and a three-jaw gland 12d. A clamping jaw is respectively provided on the outer peripheries of the inner jaw 12a, the middle jaw 12b and the outer jaw 12c. The clamping jaws are parallel to each other and the tips are flush and extend respectively in the direction of the cemented carbide wheel 9 until they abut against the outer wall of the tube sheet 18.

[0051] The inner claw 12a passes through the middle claw 12b, and the outer step at the rear end of the inner claw 12a is nested at the inner step of the middle claw 12b; the middle claw 12b passes through the outer claw 12c, and the outer step at the rear end of the middle claw 12b is nested at the inner step of the outer claw 12c. After the inner claw 12a, the middle claw 12b, and the outer claw 12c are nested and assembled, a three-claw gland 12d is screwed at the rear end of the outer claw 12c, and the inner step of the three-claw gland 12d axially positions the rear end faces of the inner claw 12a, the middle claw 12b, and the outer claw 12c. The middle claw 12b and the outer claw 12c can still rotate relative to the inner claw 12a, facilitating the triangular distribution of the three claws. The inner wall of the inner claw 12a has a female thread, and the female thread of the inner claw is screwed onto the hollow stud 17, which can adjust the axial position of the three-claw assembly 12, thereby controlling the axial position of the cemented carbide wheel 9 and controlling the cutting length of the tube head. In this way, the three-claw assembly 12 indirectly adjusts the length of the heat exchange tube 19 cut by the cemented carbide wheel 9.

[0052] Two anti-rotation rods 14 are symmetrically connected to the front end face of the hollow stud 17. The two anti-rotation rods 14 are parallel to each other and their front ends respectively pass through the axial through holes of the threaded feed sleeve 13, restricting the threaded feed sleeve 13 so that it cannot rotate. In this way, when the split shaft 4 rotates, the threaded feed sleeve 13 can only move axially, thereby driving the lever 10 to swing.

[0053] During operation, the tip of the three-claw assembly 12 abuts against the tube sheet 18, and the front ends of the locking head 1 and the split shaft 4 extend into the heat exchange tube 19 to a certain depth, which is precisely controlled by the three-claw assembly 12.

[0054] When the motor is started, the first half shaft 4a and the second half shaft 4b rotate along with the drive shaft 16. Since the anti-rotation rods 14 extend into the through holes of the threaded feed sleeve 13, the threaded feed sleeve 13 will not rotate along with the drive shaft 16. However, under the thread fit between the end of the threaded feed sleeve 13 close to the motor assembly and the first half shaft 4a, the threaded feed sleeve 13 gradually moves towards the motor assembly. The corner at the end of the threaded feed sleeve 13 close to the tube sheet 18 gradually presses down the power arm at the rear end of the lever 10, and correspondingly, the resistance arm at the front end of the lever 10 drives the slider 7 to move upward, so that the outer edge of the cemented carbide wheel 9 slowly protrudes from the annular gap between the first half shaft 4a and the second half shaft 4b, and slowly "cuts off" a small section of the heat exchange tube by means of a strong pressure, achieving the purpose of trimming the tube head.

[0055] When the motor rotates in reverse, after the threaded feed sleeve 13 returns to the forward position, the power arm of the lever 10 is released, and the tension of the return spring 5 causes the slider 7 to sink, driving the cemented carbide wheel 9 to retract into the split shaft 4, and then the device is pulled out to facilitate the cutting of the next tube head.

[0056] The above is only the preferred and feasible embodiment of the present utility model, showing and describing the basic principles, main features and advantages of the present utility model. It is not intended to limit the patent protection scope of the present utility model thereby. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. Except for the above embodiments, without departing from the spirit and scope of the present utility model, the present utility model may have other implementation manners. The present utility model will also have various changes and improvements. Any technical solutions formed by equivalent replacement or equivalent transformation shall fall within the protection scope required by the present utility model. The protection scope required by the present utility model is defined by the appended claims and their equivalents. The technical features not described in the present utility model can be realized by or adopt the prior art, and will not be elaborated herein.

Claims

1. A tube-in-tube heat exchanger flush head device, characterized in that: include: Split shaft, the front part is made up of two halves, and the rear part is a complete circle with external threads; A slider, located in the front inner cavity of the split shaft and capable of floating in the radial direction; A hard alloy wheel is fixed to the lug of the slider via a wheel axle, and the blade of the wheel rim can protrude from the annular gap of the split shaft; A lever, located in the front inner cavity of the split shaft and having a hinge fulcrum in the middle, one end of which is inserted into the bottom of the slider and the other end of which extends out from the axial long slot of the split shaft; A threaded feed sleeve is sleeved on the outer periphery of the middle section of the split shaft, the middle large diameter section forms a cavity for accommodating the lever, the front reduced diameter section is sleeved on the outer periphery of the split section of the split shaft, and the rear reduced diameter section is screwed with the outer thread of the split shaft through an internal thread; Two anti-rotation rods are provided and symmetrically pass through the axial through hole of the threaded feed sleeve.

2. The tube-in-tube heat exchanger flush head device according to claim 1, characterized in that: A return spring is supported between the top surface of the sliding block and the inner wall of the split shaft.

3. The tube-in-tube heat exchanger flush head device according to claim 1, characterized in that: The front and rear sides of the slider are respectively provided with slider grooves, and the two slider grooves are respectively embedded in the vertical rib plates on the inner wall of the split shaft.

4. The tube-in-tube heat exchanger flush head device according to claim 1, characterized in that: A bushing is arranged in the center hole of the hard alloy wheel.

5. The flush tube head device for a shell-and-tube heat exchanger according to claim 1, characterized in that: The front end of the split shaft is provided with a split shaft outer step with a reduced diameter, a locking sleeve is mounted on the split shaft outer step, the front end of the locking sleeve is provided with a locking sleeve reduced diameter section, a bearing is mounted on the locking sleeve reduced diameter section, the outer ring of the bearing fits the inner wall of the heat exchange tube, the front end of the inner ring of the bearing is pressed with a locking head, and the center screw of the locking head is screwed into the front end screw hole of the locking sleeve.

6. The flush tube head device for a shell-and-tube heat exchanger according to claim 1, characterized in that: The rear end head of the split shaft is fixedly connected to the front end of the drive shaft, the rear end of the drive shaft is connected to the output end of the reduction mechanism, the input end of the reduction mechanism is connected to the output shaft of the motor, the middle section of the drive shaft passes through the center hole of the hollow stud, and the hollow stud is fixed to the front end face of the reduction mechanism.

7. The flush tube head device for a shell-and-tube heat exchanger according to claim 6, characterized in that: The rear end of the anti-rotation rod is connected to the front end surface of the hollow stud.

8. The flush tube head device for a shell-and-tube heat exchanger according to claim 6, characterized in that: A three-claw assembly is screwed onto the hollow stud, and the front ends of the three claws of the three-claw assembly are flush and abut against the tube plate.

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