Tube plate drilling quick-change template

Abstract

The utility model provides a kind of tube plate drilling quick-change template, belong to tube plate drilling template technical field, this tube plate drilling quick-change template includes template body, positioning pin and compression plate, the template body is plate structure, several positioning holes and several drilling guide holes are set on the template body, the positioning pin is inserted in the positioning hole for with the reference hole on tube plate cooperation realizes positioning, the compression plate is located the upper surface of the template body, the compression plate is detachably connected with the template body by fastener, the compression plate is used to compress the template body and be fixed on tube plate surface, the drilling guide hole penetrates the upper surface and lower surface of the template body, the geometric center axis of the drilling guide hole is perpendicular to the lower surface of the template body;The utility model can solve the technical problem that the positioning mode of traditional template is complex and poor in stability, prone to drilling position deviation.

Description

Technical Field

[0001] This utility model belongs to the technical field of tube sheet drilling templates, and more specifically, it relates to a quick-change template for tube sheet drilling. Background Technology

[0002] In industries such as petrochemicals, power generation, and refrigeration, tube sheets are key components of equipment such as heat exchangers, condensers, and evaporators. Numerous holes need to be machined on the tube sheet for installing heat exchange tubes. Tube sheet drilling is a crucial step in the tube sheet manufacturing process. Traditional tube sheet drilling typically employs either marking or fixed drilling templates. Marking requires operators to manually mark drilling positions on the tube sheet surface according to drawings, then drill holes one by one using a drilling machine. This method suffers from low positioning accuracy, low efficiency, and requires a high level of operator skill. While fixed drilling templates can improve drilling position accuracy, different specifications and models of tube sheets have different hole layouts, requiring the creation of dedicated drilling templates for each type of tube sheet. Furthermore, when changing tubes with different hole layouts... When processing the tube sheet, it is necessary to disassemble the original template and reinstall a new one. The existing template is usually fixed directly to the surface of the tube sheet with bolts. The bolt holes on the template and the threaded holes on the tube sheet need to be aligned one by one and the bolts tightened. The installation and disassembly process is cumbersome and time-consuming. Moreover, due to the unevenness of the tube sheet surface and the positional accuracy of the threaded holes, the positioning accuracy of the template after installation is difficult to guarantee, which can easily lead to drilling position deviation and affect product quality. In addition, the existing template has a complex structure, many parts, high manufacturing cost, and difficult maintenance. Frequent template replacement during mass production seriously affects production efficiency and increases production costs. Therefore, it is urgent to develop a quick-change template device for tube sheet drilling that can be quickly replaced, accurately positioned, has a simple structure, and is easy to operate to solve the above technical problems. Utility Model Content

[0003] In view of this, the present invention provides a quick-change template for drilling holes in tube sheets, which can solve the technical problem that the positioning method of traditional templates is complicated and unstable, and is prone to drilling position deviation.

[0004] This utility model is implemented as follows:

[0005] This utility model provides a quick-change template for drilling holes in a tube sheet, including a template body, positioning pins, and a clamping plate. The template body has a plate-like structure, wherein several positioning holes and several drilling guide holes are provided on the template body. The positioning pins are inserted into the positioning holes to cooperate with the reference holes on the tube sheet for positioning. The clamping plate is located on the upper surface of the template body and is detachably connected to the template body by fasteners. The clamping plate is used to press and fix the template body to the surface of the tube sheet. The drilling guide holes penetrate the upper and lower surfaces of the template body, and the geometric center axis of the drilling guide holes is perpendicular to the lower surface of the template body. The lower end face of the positioning pins is located on the same plane as the lower surface of the template body.

[0006] The technical advantages of the quick-change template for tube sheet drilling provided by this utility model are as follows: By setting a structure in which the positioning pin is inserted into the positioning hole and matches the reference hole of the tube sheet, the template body is accurately positioned on the surface of the tube sheet. The detachable connection between the clamping plate and the template body enables quick installation and disassembly. The design that the lower end face of the positioning pin and the lower surface of the template body are on the same plane ensures that the template body and the surface of the tube sheet are closely fitted. The design that the geometric center axis of the drilling guide hole is perpendicular to the lower surface of the template body ensures the verticality of the drilling. The overall structure is simple and easy to operate, meeting the need for quick template replacement in tube sheet drilling operations.

[0007] Based on the above technical solution, the quick-change template for drilling holes in tube sheets of this utility model can be further improved as follows:

[0008] The thickness of the template body is 1:1 to the depth of the drilling guide hole, and the inner wall surface of the drilling guide hole is a smooth cylindrical surface.

[0009] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the thickness of the template body and the depth of the drilling guide hole are kept in a 1:1 ratio, so that the drilling guide hole has sufficient guiding length to ensure the stability of the drill bit. At the same time, the design of the inner wall surface of the drilling guide hole as a smooth cylindrical surface reduces the frictional resistance of the drill bit during the drilling process, reduces the wear of the drill bit, improves the drilling accuracy and efficiency, and ensures the accuracy of the drilling position.

[0010] Furthermore, the locating pin has a cylindrical structure, and the fit between the outer diameter of the locating pin and the inner diameter of the locating hole is a transition fit.

[0011] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the positioning pin adopts a cylindrical structure design, which makes it easy to insert into the positioning hole and the tube sheet reference hole. The outer diameter of the positioning pin and the inner diameter of the positioning hole adopt a transition fit method, which not only ensures that the positioning pin and the positioning hole have a certain fit accuracy to achieve accurate positioning, but also makes the positioning pin relatively easy to insert and pull out, which facilitates the installation and disassembly of the template body, improves the efficiency of template replacement, and meets the needs of frequent template replacement operations.

[0012] Furthermore, the clamping plate has a rectangular frame structure, and the distance between the inner edge of the clamping plate and the outer edge of the drilling guide hole is greater than the diameter of the positioning hole.

[0013] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: The clamping plate adopts a rectangular frame structure design, which reduces the weight of the clamping plate while ensuring the clamping and fixing function. The distance between the inner edge of the clamping plate and the outer edge of the drilling guide hole is greater than the diameter of the positioning hole, which avoids the clamping plate from blocking the drilling guide hole area, ensuring that the drill bit can smoothly enter the drilling guide hole for drilling operations. At the same time, it provides sufficient operating space for drilling operations, improving the convenience and safety of the operation.

[0014] Furthermore, the template body has a plurality of mounting holes around its perimeter, and the distance between the geometric center of the mounting holes and the geometric center of the template body is equal.

[0015] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: Several mounting holes are set around the template body, and the distance between the geometric center of the mounting holes and the geometric center of the template body is equal, forming a symmetrically distributed mounting hole layout. This makes the clamping force applied to the template body by the clamping plate through the fasteners evenly distributed, avoiding deformation or displacement of the template body due to uneven force, ensuring the stability of the template body on the tube sheet surface, and improving the positional accuracy and quality of drilling.

[0016] Furthermore, the upper end of the positioning pin is provided with a boss structure, the outer diameter of the boss structure is larger than the inner diameter of the positioning hole, and the bottom surface of the boss structure abuts against the upper surface of the template body.

[0017] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: The upper end of the positioning pin is provided with a boss structure. The design of the outer diameter of the boss structure being larger than the inner diameter of the positioning hole allows the boss structure to limit the insertion depth of the positioning pin in the positioning hole. The design of the bottom surface of the boss structure abutting against the upper surface of the template body ensures that the lower end face of the positioning pin and the lower surface of the template body are located on the same plane, ensuring full contact between the positioning pin and the reference hole of the tube sheet, improving the reliability and stability of positioning. At the same time, the boss structure facilitates the installation and removal of the positioning pin by the operator.

[0018] Furthermore, the drilling guide holes are arranged in an array on the template body, and the distance between the geometric centers of two adjacent drilling guide holes is greater than twice the diameter of the drilling guide hole.

[0019] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the design of the drilling guide holes being distributed in an array on the template body facilitates the batch processing of multiple holes on the tube sheet. The design that the distance between the geometric centers of two adjacent drilling guide holes is greater than twice the diameter of the drilling guide hole ensures that there is sufficient wall thickness between adjacent drilling guide holes, avoids the reduction of template body strength or deformation due to insufficient wall thickness during the drilling process, ensures the service life of the template body and the drilling accuracy, and meets the operation requirements of dense drilling of tube sheets.

[0020] Furthermore, the lower surface of the template body is provided with several protrusions, which are distributed in a ring around the drill guide hole.

[0021] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: The lower surface of the template body is provided with a ring of protrusions distributed around the drilling guide hole. The protrusions form local support when the template body contacts the tube sheet surface, reducing the contact area between the lower surface of the template body and the tube sheet surface, reducing the positioning error caused by the unevenness of the tube sheet surface. At the same time, the protrusions facilitate the removal of chips and coolant generated during the drilling process, avoiding the accumulation of chips between the template body and the tube sheet, which affects the positioning accuracy and improves the reliability of the drilling operation.

[0022] Furthermore, the template body is made of alloy steel, and the positioning pin is made of stainless steel.

[0023] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the template body is made of alloy steel, which has high strength and hardness and can withstand the impact and cutting force of the drill bit on the template body during drilling operations, ensuring that the template body is not easily deformed during long-term use. The positioning pin is made of stainless steel, which has good corrosion resistance and can adapt to the use requirements of different working conditions, extending the service life of the positioning pin and reducing maintenance costs.

[0024] Furthermore, the upper surface of the clamping plate is provided with an anti-slip texture, which is a cross-shaped groove structure.

[0025] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: The anti-slip texture with a cross-groove structure on the upper surface of the pressure plate increases the friction between the operator's hand or tool and the pressure plate, making it easier for the operator to grip and apply force when installing and removing the pressure plate, preventing slippage caused by the smooth surface of the pressure plate, improving the safety and efficiency of operation. At the same time, the anti-slip texture also enhances the aesthetics of the pressure plate and improves the overall quality of the product.

[0026] Compared with existing technologies, the advantages of this utility model for quick-change templates for drilling tube sheets are as follows: This utility model achieves precise positioning through a structure where positioning pins and positioning holes cooperate, and it also achieves quick fixing through a detachable connection between the clamping plate and the template body. This fundamentally solves the technical problems of cumbersome template replacement and poor positioning accuracy in existing technologies. The method of inserting the positioning pin into the positioning hole and cooperating with the tube sheet reference hole ensures the positioning accuracy of the template body on the tube sheet surface. The design that the lower end face of the positioning pin and the lower surface of the template body are on the same plane ensures the reliability of positioning. The clamping plate achieves quick installation and disassembly through fasteners. This design significantly shortens template replacement time and improves production efficiency. The design of the drill guide hole's geometric center axis being perpendicular to the lower surface of the template body ensures the verticality and positional accuracy of the drilling. The protrusions reduce the impact of unevenness on the tube sheet surface on positioning accuracy. The design of maintaining sufficient distance between adjacent drill guide holes ensures the strength and service life of the template body. The overall structure is simple and reasonable, with fewer parts, low manufacturing cost, and convenient and quick operation. It is suitable for drilling operations on tube sheets of various specifications and has good versatility and practicality. Compared with existing technologies, it has significantly improved in terms of positioning accuracy, replacement efficiency, and ease of use. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A cross-sectional view of a quick-change template for drilling holes in a tube sheet;

[0029] Figure 2 A top view of the template body of a quick-change template for drilling holes in a tube sheet;

[0030] Figure 3 This is a top view of a quick-change template for drilling holes in a tube sheet;

[0031] The attached diagram lists the components represented by each number as follows:

[0032] 10. Template body; 11. Positioning hole; 12. Drilling guide hole; 13. Mounting hole; 14. Protrusion; 20. Positioning pin; 21. Boss structure; 30. Pressure plate; 31. Anti-slip texture. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.

[0034] like Figure 1-3 The image shows an embodiment of a quick-change template for drilling holes in a tube sheet provided by this utility model. In this embodiment, it includes a template body 10, a positioning pin 20, and a clamping plate 30. The template body has a plate-like structure, wherein a plurality of positioning holes 11 and a plurality of drilling guide holes 12 are provided on the template body. The positioning pin is inserted into the positioning hole to cooperate with the reference hole on the tube sheet to achieve positioning. The clamping plate 30 is located on the upper surface of the template body and is detachably connected to the template body by fasteners. The clamping plate is used to press and fix the template body to the surface of the tube sheet. The drilling guide hole penetrates the upper and lower surfaces of the template body. The geometric center axis of the drilling guide hole is perpendicular to the lower surface of the template body. The lower end face of the positioning pin is located on the same plane as the lower surface of the template body.

[0035] In the above technical solution, the ratio of the thickness of the template body to the depth of the drilling guide hole is 1:1, and the inner wall surface of the drilling guide hole is a smooth cylindrical surface.

[0036] Furthermore, in the above technical solution, the locating pin has a cylindrical structure, and the fit between the outer diameter of the locating pin 20 and the inner diameter of the locating hole is a transition fit.

[0037] Furthermore, in the above technical solution, the clamping plate has a rectangular frame structure, and the distance between the inner edge of the clamping plate and the outer edge of the drilling guide hole is greater than the diameter of the positioning hole.

[0038] Furthermore, in the above technical solution, a number of mounting holes 13 are provided around the periphery of the template body, and the distance between the geometric center of the mounting hole and the geometric center of the template body is equal.

[0039] Furthermore, in the above technical solution, the upper end of the positioning pin is provided with a boss structure 21, the outer diameter of the boss structure is larger than the inner diameter of the positioning hole, and the bottom surface of the boss structure abuts against the upper surface of the template body.

[0040] Furthermore, in the above technical solution, the drilling guide holes are arranged in an array on the template body, and the distance between the geometric centers of two adjacent drilling guide holes is greater than twice the diameter of the drilling guide hole.

[0041] Furthermore, in the above technical solution, the lower surface of the template body is provided with a number of protrusions 14, which are distributed in a ring around the drilling guide hole.

[0042] Furthermore, in the above technical solution, the template body is made of alloy steel, and the positioning pin is made of stainless steel.

[0043] Furthermore, in the above technical solution, the upper surface of the pressing plate is provided with anti-slip texture 31, which is a cross groove structure.

[0044] The operator first selects the appropriate template body according to the hole layout of the tube sheet to be processed. They then check the integrity of the positioning holes, drilling guide holes, and positioning pins on the template body, confirming there is no wear or deformation. After confirming there is no wear, the template body is placed on the approximate position on the tube sheet surface, ensuring the positioning holes of the template body are initially aligned with the pre-machined reference holes on the tube sheet. Next, the positioning pins are inserted into the positioning holes of the template body, and simultaneously, the lower end of the positioning pin is inserted into the reference hole of the tube sheet. Because the outer diameter of the positioning pin and the inner diameter of the positioning hole use a transition fit, the positioning pin can be inserted relatively easily. During insertion, it is necessary to ensure that the bottom surface of the boss structure of the positioning pin is fully abutted against the upper surface of the template body. At this point, the lower end face of the positioning pin and the lower surface of the template body are on the same plane, achieving precise positioning of the template body on the tube sheet surface. Next, the clamping plate is placed on the upper surface of the template body, aligning the mounting holes on the clamping plate with the mounting holes around the template body. The clamping plate is then tightened... The fasteners pass through the mounting holes of the clamping plate and the template body and are tightened. The clamping plate firmly presses and fixes the template body to the surface of the tube sheet. When tightening the fasteners, the force should be applied evenly in a diagonal sequence to ensure uniform distribution of the clamping force. After the template is installed, the operator uses a drill press or hand drill to align the drill bit with the drilling guide hole on the template body. The drill bit enters the tube sheet vertically through the drilling guide hole to perform drilling operations. During the drilling process, the smooth cylindrical surface of the inner wall of the drilling guide hole guides and supports the drill bit, ensuring the verticality and positional accuracy of the drilling. The protrusions on the lower surface of the template body provide support during the drilling process, and the chips and coolant are discharged through the gaps between the protrusions. After all the holes of a tube sheet are drilled, the operator loosens the fasteners in a diagonal sequence, removes the clamping plate, and then pulls out the positioning pins in sequence to remove the template body, completing the template disassembly. The entire replacement process is quick and convenient, improving production efficiency.

[0045] The following is a specific embodiment 1 of this utility model: This embodiment provides a quick-change template for drilling holes in a circular tube sheet with a diameter of 800mm. The template body is made of 45 alloy steel and is machined by a CNC milling machine. The template body has a circular plate structure with an outer diameter of 820mm and a thickness of 15mm. The upper and lower surfaces of the template body are precision ground to a surface roughness of Ra1.6, ensuring surface flatness. A central positioning hole is provided at the geometric center of the template body, and three auxiliary positioning holes are evenly distributed on the circumference at a distance of 120mm from the geometric center. The positioning holes have an inner diameter of 12mm and a depth of 15mm. The inner wall surface of the positioning holes is reamed to ensure hole diameter accuracy and surface quality. 169 drill guide holes are arranged in an equilateral triangular grid pattern on the template body, with the center as the origin. The distance between the geometric centers of adjacent drill guide holes is 25mm. The inner diameter of each drill guide hole is 19mm and the depth is 15mm. The drill guide holes penetrate both the upper and lower surfaces of the template body. The geometric center axis of the drill guide holes is precision bored to ensure it is perpendicular to the lower surface of the template body, with a perpendicularity error controlled within 0.02mm. The inner wall surface of the hole is honed to form a smooth cylindrical surface with a surface roughness of Ra0.8. Eight mounting holes are evenly distributed circumferentially around the template body. The distance between the geometric center of each mounting hole and the geometric center of the template body is 380mm. The inner diameter of each mounting hole is 9mm, used for M8 bolts. On the lower surface of the template body, four protrusions are provided around each drill guide hole. These protrusions are hemispherical in shape, with a radius of 2mm and a height of 0.5mm. They are evenly distributed on the circumference at a distance of 15mm from the geometric center of the drill guide hole. The protrusions are precision machined. To ensure dimensional accuracy, the locating pin is made of 304 stainless steel and has a cylindrical structure. The outer diameter of the locating pin is 11.98mm and the length is 30mm. The outer diameter of the locating pin and the inner diameter of the locating hole form an H7 or h6 transition fit, ensuring positioning accuracy and ease of assembly and disassembly. The upper end of the locating pin has a boss structure with an outer diameter of 18mm and a thickness of 3mm. The bottom surface of the boss structure is precision machined to ensure a tight fit with the upper surface of the template body. The lower end face of the locating pin is ground to be on the same plane as the lower surface of the template body, and the surface flatness error is controlled within 0.Within 0.1mm, the clamping plate is made of 45# alloy steel. The clamping plate has a rectangular frame structure with dimensions of 850mm x 850mm, a frame width of 40mm, and a thickness of 10mm. The distance between the inner edge of the clamping plate and the outer edge of the drill guide hole is 35mm, which is 12mm larger than the diameter of the positioning hole, ensuring that the drill guide hole area is not obstructed. The upper surface of the clamping plate has a cross-grooved anti-slip texture, with a groove width of 2mm, a depth of 1mm, and a spacing of 10mm between grooves. The clamping plate has 8 mounting holes, the positions of which correspond one-to-one with the mounting holes around the template body. M8 socket head cap bolts and nuts are used as fasteners. The bolt is 40mm long, made of 35# steel with a blackening treatment, and the nut is made of 45# steel. When using the quick-change template for drilling tube sheets in this embodiment, the positioning pin achieves accurate positioning of the template body through the precise fit between the positioning hole and the tube sheet reference hole. The clamping plate firmly fixes the template body to the tube sheet surface with fasteners. The drilling guide hole precisely guides the drill bit, ensuring a drilling position accuracy within 0.05mm. The template installation time is controlled within 3 minutes, and the disassembly time is controlled within 2 minutes, significantly improving production efficiency. The protrusion effectively reduces the impact of tube sheet surface unevenness on positioning accuracy and facilitates the discharge of chips and coolant, ensuring drilling quality.

[0046] The following is another specific embodiment 2 of this utility model: Embodiment 2 is based on Embodiment 1, but the boss structure of the positioning pin is changed to a conical structure. The outer diameter of the upper end of the conical structure is 18mm, the outer diameter of the lower end is 13mm, the angle between the conical surface and the axis of the positioning pin is 15 degrees, and the height of the conical structure is 5mm. This conical design provides a guiding function for the positioning pin when inserted into the positioning hole, facilitating quick alignment and insertion. Simultaneously, the lower outer diameter of the conical structure maintains a transition fit with the inner diameter of the positioning hole, ensuring positioning accuracy. The surface of the conical structure is polished, achieving a surface roughness of Ra0.4, further reducing insertion resistance. On the lower surface of the body, the shape of the protrusion is changed from hemispherical to frustum. The upper base diameter of the frustum is 3mm, the lower base diameter is 5mm, and the height is 1mm. The angle between the side of the frustum and the lower surface of the template body is 30 degrees. The frustum-shaped protrusion increases the contact area with the tube sheet surface, improving the stability of the support. At the same time, the inclined design of the side of the frustum facilitates the chips to slide out along the inclined surface, further improving the chip removal effect. The improved design of the positioning pin and the protrusion in this embodiment improves the convenience of template installation and the chip removal effect. The drilling position accuracy is maintained within 0.05mm, the template installation time is shortened to 2.5 minutes, and the chip cleaning during the drilling process is smoother.

[0047] The following is another specific embodiment 3 of this utility model: Embodiment 3 is based on Embodiment 1, with several elastic pads added to the lower surface of the pressing plate. The elastic pads are made of nitrile rubber and have a rectangular block structure, with a length of 30mm, a width of 20mm, and a thickness of 5mm. The elastic pads are evenly distributed along the inner edge of the pressing plate and are fixed to the lower surface of the pressing plate with adhesive. The elastic pads act as a buffer when the pressing plate presses against the template body, avoiding localized stress concentration caused by direct rigid contact between the pressing plate and the template body. Simultaneously, the elastic pads can adapt to minor unevenness on the tube sheet surface, making the pressing force distribution more uniform around the template body. A reinforcing rib structure is added near the mounting hole. The reinforcing rib is a triangular plate-shaped structure with a base length of 25mm, a height of 10mm, and a thickness of 5mm. The reinforcing rib is perpendicularly connected to the upper surface of the template body and is located between the mounting hole and the geometric center of the template body. The addition of the reinforcing rib enhances the local strength of the template body near the mounting hole, avoids local deformation caused by tightening fasteners, and ensures the overall flatness of the template body. The addition of elastic pads and reinforcing ribs in this embodiment further improves the compression stability and structural strength of the template body, improves the drilling position accuracy to within 0.03mm, extends the service life of the template, and is suitable for tube sheet drilling operations with higher precision requirements.

[0048] Specifically, the principle of this utility model is as follows: This utility model adopts a positioning method that uses a positioning pin, a positioning hole, and a tube sheet reference hole to cooperate. The positioning reference of the template is transferred from the threaded hole on the tube sheet surface to a pre-machined high-precision reference hole on the tube sheet. Since the positional and shape accuracy of the reference hole is much higher than that of the threaded hole, the template body can be accurately positioned on the tube sheet surface after the positioning pin is inserted into the positioning hole and the reference hole. The design that the lower end face of the positioning pin is on the same plane as the lower surface of the template body ensures that the positioning pin can be fully inserted into the tube sheet reference hole, avoiding positioning instability caused by insufficient insertion depth. The clamping plate is detachably connected to the template body through fasteners, separating the template's fixing and positioning functions. The clamping plate only serves to press and fix the template body to the tube sheet surface and does not participate in positioning. The number and position of the fasteners are designed according to the size and stress of the template body to ensure uniform distribution of clamping force. This separate design greatly simplifies the installation and disassembly process of the template. Operators only need to first... Positioning is achieved by inserting the positioning pin into the positioning hole and the reference hole, and then tightening the fastener to complete the clamping and fixing. To disassemble, first loosen the fastener and then pull out the positioning pin. The whole process is quick and convenient. The design of the geometric center axis of the drilling guide hole being perpendicular to the lower surface of the template body is based on the principle that the drill bit needs to maintain vertical feed during drilling, ensuring that the drill bit enters the tube sheet in the correct direction. The design of the inner wall of the drilling guide hole as a smooth cylindrical surface reduces the frictional resistance of the drill bit and avoids drill bit deflection. The lower surface of the template body is provided with annularly distributed protrusions, which form a stable support structure between the template body and the tube sheet surface based on the principle of three-point or multi-point support, reducing the positioning error caused by the unevenness of the tube sheet surface. The annular distribution of the protrusions also forms a chip removal channel, which facilitates the discharge of chips and coolant and avoids the accumulation of chips affecting the positioning accuracy. Through the comprehensive application of the above-mentioned multiple technical measures, this utility model realizes the rapid replacement, precise positioning and stable fixing of the tube sheet drilling template, thereby solving the technical problems existing in the prior art.

[0049] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A quick-change template for drilling holes in tube sheets, comprising a template body, positioning pins, and a clamping plate, wherein the template body is a plate-like structure, characterized in that, The template body has several positioning holes and several drilling guide holes. The positioning pin is inserted into the positioning hole to cooperate with the reference hole on the tube sheet to achieve positioning. The clamping plate is located on the upper surface of the template body. The clamping plate is detachably connected to the template body by fasteners. The clamping plate is used to press and fix the template body to the surface of the tube sheet. The drilling guide hole penetrates the upper and lower surfaces of the template body. The geometric center axis of the drilling guide hole is perpendicular to the lower surface of the template body. The lower end face of the positioning pin is located on the same plane as the lower surface of the template body.

2. The quick-change template for drilling holes in a tube sheet according to claim 1, characterized in that, The thickness of the template body is 1:1 to the depth of the drilling guide hole, and the inner wall surface of the drilling guide hole is a smooth cylindrical surface.

3. A quick-change template for drilling holes in a tube sheet according to claim 2, characterized in that, The locating pin has a cylindrical structure, and the fit between the outer diameter of the locating pin and the inner diameter of the locating hole is a transition fit.

4. A quick-change template for drilling holes in a tube sheet according to claim 3, characterized in that, The clamping plate has a rectangular frame structure, and the distance between the inner edge of the clamping plate and the outer edge of the drilling guide hole is greater than the diameter of the positioning hole.

5. A quick-change template for drilling holes in a tube sheet according to claim 4, characterized in that, The template body has a plurality of mounting holes around its perimeter, and the distance between the geometric center of the mounting holes and the geometric center of the template body is equal.

6. A quick-change template for drilling holes in a tube sheet according to claim 5, characterized in that, The upper end of the positioning pin is provided with a boss structure, the outer diameter of the boss structure is larger than the inner diameter of the positioning hole, and the bottom surface of the boss structure abuts against the upper surface of the template body.

7. A quick-change template for drilling holes in a tube sheet according to claim 6, characterized in that, The drilling guide holes are arranged in an array on the template body, and the distance between the geometric centers of two adjacent drilling guide holes is greater than twice the diameter of the drilling guide hole.

8. A quick-change template for drilling holes in a tube sheet according to claim 7, characterized in that, The lower surface of the template body is provided with several protrusions, which are distributed in a ring around the drill guide hole.

9. A quick-change template for drilling holes in a tube sheet according to claim 8, characterized in that, The template body is made of alloy steel, and the positioning pin is made of stainless steel.

10. A quick-change template for drilling holes in a tube sheet according to claim 9, characterized in that, The upper surface of the clamping plate is provided with anti-slip texture, which is a cross groove structure.

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