Gluing method for joint surface of end face connection sealing structure

Abstract

The invention belongs to the technical field of machining technologies, and particularly relates to an end face connection sealing structure bonding surface gluing method which comprises the steps that a sealing surface is divided; determining a sealant smearing route and position; and calculating the diameter of the sealant column. According to the method, the joint surface is divided into the sealing surface and the non-sealing surface according to the position of the bolt hole, the sealing effect can be achieved only by gluing the sealing surface, and the gluing amount is greatly reduced. The method comprises the following steps: selecting a connecting line between bolt holes as a gluing route according to a sealant sealing principle and a stress principle generated by maximum pre-tightening; according to the principle that the sealant is not easy to extrude out of the junction surface and the idea that only the sealing surface needs to be coated, the sealant coating position between the bolt hole and the inner edge of the junction surface is 1 / 2 of the distance between the bolt hole and the inner edge of the junction surface, so that when the sealant is extruded to deform into a glue film, the expansion range is not easy to exceed the edge of the bolt hole and the inner edge of the junction surface; and the adhesive film is uniformly distributed in the area of the sealing tape.

Description

Technical Field

[0001] The present invention belongs to the technical field of machining processes, and particularly relates to a method for applying glue to the joint surface of an end-face connection sealing structure. Background Art

[0002] For complex machinery and mechatronic products to achieve their functions and performances, they generally consist of multiple components. Connections are required between the various components, and the connection parts often need to be sealed. Among them, the connection method where different components are joined by end faces (flat surfaces) is the most common. Its connection structure is as Figure 1 shown, mainly consisting of four parts: a connecting member 3 (bolt), part 1, part 2, and sealant 4. Among them, part 1 and part 2 are each joined to the other by their respective end faces (flat surfaces). The connecting member serves to tightly join part 1, part 2, and the sealant together. The sealant is used for gap compensation between part 1 and part 2 to achieve sealing.

[0003] The existing technology mainly includes three aspects. First, according to industry experience and relevant specifications, fasteners (bolts) are designed to determine the specifications, models, quantities, bolt distribution positions, etc. of the bolts, and the tightening torque of the bolts is determined according to national standards. Second, to ensure good sealing performance, the entire joint surface is often regarded as the sealing surface (sealing band), and it is coated with sealant to achieve reliable sealing. Third, when applying sealant, the amount of sealant is generally specified as "appropriate" in terms of usage, and the technical requirements are not clear and definite enough.

[0004] There are two serious problems in the existing technology. On the first hand, when the entire joint surface is used as the sealing surface (sealing band) and fully coated with glue, generally the area of the joint surface is about twice that of the sealing surface. Therefore, fully coating with glue will consume about twice as much sealant, resulting in an increase in product cost. In addition, when the entire joint surface is used as the sealing surface for applying glue, although it seems beneficial for ensuring sealing performance, when a large amount of sealant is under the action of the pre-tightening force, it will inevitably expand outward as the glue film thins. A large amount of sealant will flow out from the joint surface, or enter the product interior from the inner edge of the joint surface, affecting cleanliness, or be extruded from the bolt holes, affecting the aesthetics of the product and the cleanliness of the bolt threads, or overflow from the outer edge of the joint surface into the natural environment, greatly affecting the aesthetics of the product and environmental protection. On the second hand, when applying "appropriate" sealant, due to the lack of quantitative requirements, there may be a situation where the sealing performance is affected due to too little sealant being applied; it is also possible to apply too much sealant, such that when the bolts are tightened, the sealant is extruded, resulting in problems such as contamination and affecting aesthetics. Summary of the Invention

[0005] (I) Technical Problems to be Solved

[0006] The technical problem to be solved by the present invention is as follows: For the end-face connection structure commonly used in the mechanical and mechatronic fields, the glue application area on the joint surface is unreasonably set, the glue application position is not optimal, and there is a lack of a calculation method for the glue application amount, resulting in problems such as seal failure, large glue consumption, and pollution caused by excess sealant. A seal surface setting method, a sealant application route, and a calculation formula for the diameter of the sealant column are proposed to achieve the implementation effects of reliable sealing, less glue consumption, and reduced pollution, and to solve the serious problems brought about by the insufficient sealant sealing technology of the end-face connection structure.

[0007] (II) Technical Solution

[0008] To solve the above technical problem, the present invention provides a method for applying sealant to the joint surface of an end-face connection seal structure, and the method includes:

[0009] Step 1: Divide the seal surface (seal band);

[0010] Step 2: Determine the sealant application route and position;

[0011] Step 3: Calculate the diameter of the sealant column.

[0012] Among them, in the above-mentioned Step 1, divide the seal surface (seal band);

[0013] The basic principle of sealant to achieve sealing is that the sealant compensates for the gap generated between two components at the joint surface due to manufacturing errors. For the sealant to play a role, it is necessary to rely on fasteners (bolts) to tightly fit the two components and the sealant together through the pre-tightening force. Therefore, any place where there is an external leakage channel belongs to the ineffective sealing area, which is defined as the non-seal surface, and it is only necessary to apply glue to the seal surface; as Figure 2 shown, the joint surface is divided into a seal surface and a non-seal surface. In the area outside the threaded hole, when the internal medium of the product moves from the inside to the bolt hole, it can leak through the bolt hole. Therefore, the area outside the bolt hole belongs to the non-sealing area.

[0014] Among them, in the above-mentioned Step 2, determine the sealant application route and position;

[0015] Although applying sealant to the entire joint surface can ensure sufficient sealing, due to its large glue application area, the glue consumption is large, and the excess sealant (especially near the edge) overflows under the action of the bolt pre-tightening force, causing a large amount of pollution hazards. To solve this problem, it is necessary to find the position where the sealant can play a key role, so as to determine the sealant application route.

[0016] Obviously, the non-sealing surface does not need to be coated with glue. Therefore, the glue coating area is determined within the sealing surface (sealing strip); also, since the key factor for the sealing glue to function is the existence of fastening force, the glue coating route between two bolt holes is determined as the connection line of the two bolt holes (because each position on this route is the position of the maximum stress generated by the maximum pre-tightening force, which is most conducive to the tight fit of the sealing glue); considering that the sealing glue will transform into a glue film and spread outward during extrusion, to ensure that the sealing glue does not spread beyond the sealing surface and cause pollution, within the diameter range of the threaded hole, the position of the glue coating is at the 1 / 2 position along the distance between the threaded hole and the inner edge of the joint surface, as Figure 3 shown, is a case diagram of the glue coating position and route.

[0017] Among them, in the said step 2, when the distribution route of the fasteners is not a straight line (such as a 90-degree angle), then the intersection route of its distribution direction is used as the glue coating route; if the fasteners are distributed in a circle, the glue coating route is carried out along the circular arc route on the pitch circle of the fasteners;

[0018] Let the distance between the bolt hole and the inner edge be x, then the distance from the glue coating position to the inner edge should be x / 2; let the radius of the threaded hole be r, then the diameter of the circular arc route of the glue coating along the periphery of the threaded hole should be: R = r + x / 2;

[0019] Therefore, the method for determining the glue coating route is as follows:

[0020] (1) The diameter of the circular arc route of the glue coating around the bolt hole is: R = r + x / 2;

[0021] (2) The straight line route of the glue coating at the position without bolt holes is the connection line of the bolt hole centers;

[0022] (3) The intersection point where the circular arc route specified in (1) above and the straight line route specified in (2) meet is the turning point of the glue coating route.

[0023] Among them, in the said step 4, calculate the diameter of the sealing glue column;

[0024] The sealing glue is generally stored in a sealed plastic tube. Before use, a circular small hole needs to be cut at the head of the plastic tube, and the sealing glue is extruded from the plastic tube by using a special tooling. Therefore, the extruded sealing glue is in a cylindrical shape, called a glue column. Obviously, the diameter of the glue column determines the amount of the sealing glue used. To accurately control the amount of the glue coating, only the diameter of the glue column needs to be accurately calculated, that is, the diameter of the circular small hole cut in the plastic tube;

[0025] The said step 4 includes the following sub-steps:

[0026] Step 41: Determine the form and position tolerance of the joint surface;

[0027] Step 42: Calculate the maximum clearance of the joint surface;

[0028] Step 43: Calculate the thickness of the adhesive film;

[0029] Step 44: Determine the width of the sealing surface;

[0030] Step 45: Calculate the diameter of the adhesive column;

[0031] Step 46: Control of the glue outlet hole.

[0032] Among them, in the said step 41, determine the geometric tolerance of the joint surface;

[0033] Suppose the end faces of two parts jointly form the joint surface, which are plane A and plane B respectively. The flatness of plane A is a (mm), and the flatness of plane B is b (mm).

[0034] Among them, in the said step 42, calculate the maximum gap of the joint surface;

[0035] When the maximum protruding or recessed positions of plane A and plane B exactly coincide at the same position, the maximum gap is obtained at this position of the joint surface, or the maximum protruding point makes the maximum gap obtained at other positions. Therefore, calculate the maximum gap h = a + b.

[0036] Among them, in the said step 43, calculate the thickness of the adhesive film;

[0037] The sealant fully fills the gap of the joint surface; considering that when the sealant solidifies from liquid to solid, its volume shrinkage coefficient α is 0.9 - 1.0, so the thickness of the adhesive film δ = h / α = (a + b) / α.

[0038] Among them, in the said step 44, determine the width of the sealing surface;

[0039] As Figure 2 shown, define the width of the sealing surface as l (mm);

[0040] The width of the joint surface is L, and the diameter of the bolt hole is D;

[0041] Step 45: Calculate the diameter of the adhesive column;

[0042] According to the principle that the volume of the sealant remains unchanged during the extrusion deformation process, assume the diameter of the sealant column is d, and the length of the adhesive column is s, then the volume of the adhesive column is After the adhesive column is extruded into an adhesive film, the volume V2 = δ × l × s. Since V1 = V2, we can get Solve to get: d =

[0044] Among them, in the said step 46, control of the glue outlet hole;

[0045] It is very difficult to cut a diameter d at the glue outlet of the plastic bottle of the gluing tool with scissors. A reaming tool with a diameter of d can be pre-processed on a lathe and used to ream the glue outlet of the plastic bottle, which can more easily ensure that the glue output reaches the expected target.

[0046] (III) Beneficial effects

[0047] 1. Compared with the prior art, the main innovative points of the present invention are as follows:

[0048] (1) Sealing surface division method.

[0049] The joint surface is divided into a sealing surface and a non-sealing surface according to the position of the bolt holes. Only applying glue to the sealing surface can achieve the sealing effect, thus greatly reducing the glue application amount (reducing by about 50%), and at the same time greatly reducing the pollution problem caused by excessive glue application.

[0050] (2) Glue application position and route.

[0051] According to the sealing principle of the sealant and based on the principle of the stress generated by the maximum pre-tightening, the connection line between the bolt holes is selected as the glue application route between the bolt holes; based on the principle that the sealant is not easily extruded from the joint surface and the idea of only applying glue to the sealing surface, between the bolt hole and the inner edge of the joint surface, the glue application position is at 1 / 2 of the distance between the bolt hole and the inner edge of the joint surface. Applying glue in this way can ensure that when the sealant is extruded and deformed into a glue film, the expansion range is not easily exceeded beyond the bolt hole edge and the inner edge of the joint surface, so that the glue film is evenly distributed in the sealing band area.

[0052] (3) Method for determining the diameter of the sealant column.

[0053] To achieve precise control of the glue consumption, this solution gives a formula for solving the diameter of the glue column in 6 steps. The core point is to determine the glue consumption based on the joint surface clearance value and follow the principle that the volume of the sealant remains unchanged before and after extrusion deformation.

[0054] 2. Adopting the technical solution of the present invention can achieve the following three remarkable effects:

[0055] (1) Realize quantitative and precise control of the glue consumption, so as to ensure good sealing of the product joint surface while not causing the sealant to be extruded into the product interior to affect the cleanliness or be extruded to the product exterior to affect the appearance and natural environmental protection due to excessive glue application.

[0056] (2) By dividing the sealing surface (sealing band) in the joint surface, the glue application area and glue consumption can be reduced by about 50%, thereby improving the product economy and competitiveness.

[0057] (3) By determining the position and route of sealant application, it is possible to effectively prevent the sealant from being extruded from the joint surface and ensure that the sealant is located in the area with greater pre-tightening force, thereby improving the sealing performance. Description of the Drawings

[0058] Figure 1 It is a schematic diagram of the composition of the end-face connection structure.

[0059] Figure 2 It is a schematic diagram of the joint surface, sealing surface, and non-sealing surface.

[0060] Figure 3 It is a case diagram of the sealant application position and route.

[0061] Figure 4 It is a partial case diagram of the sealant application position and route.

[0062] Figure 5 It is the effect diagram after applying the sealant and tightening. Detailed Implementation Manner

[0063] To make the objectives, content, and advantages of the present invention clearer, the following further describes in detail the specific implementation manner of the present invention with reference to the drawings and embodiments.

[0064] To solve the above technical problems, the present invention provides a method for applying sealant to the joint surface of an end-face connection sealing structure, and the method includes:

[0065] Step 1: Divide the sealing surface (sealing band);

[0066] Step 2: Determine the sealant application route and position;

[0067] Step 3: Calculate the diameter of the sealant column.

[0068] Among them, in the above Step 1, divide the sealing surface (sealing band);

[0069] The basic principle of the sealant to achieve sealing is that the sealant compensates for the gap generated between two components at the joint surface due to manufacturing errors. For the sealant to play a role, it relies on fasteners (bolts) to tightly fit the two components and the sealant together through pre-tightening force. Therefore, any place with a leakage channel belongs to the ineffective sealing area, which is defined as the non-sealing surface, and only the sealing surface needs to be coated with sealant; as Figure 2 shown, the joint surface is divided into a sealing surface and a non-sealing surface. In the area outside the threaded hole, when the internal medium of the product moves from the inside to the bolt hole, it can leak through the bolt hole. Therefore, the area outside the bolt hole belongs to the non-sealing area.

[0070] Among them, in the above Step 2, determine the sealant application route and position;

[0071] Although applying glue to the entire joint surface can ensure sufficient sealing, the large glue application area results in a large amount of glue consumption. Excess sealant (especially near the edge) overflows under the action of bolt pre-tightening force, causing a large amount of pollution hazards. To solve this problem, it is necessary to find the position where the sealant can play a key role, so as to determine the sealant application route.

[0072] Obviously, the non-sealing surface does not need to be coated with glue. Therefore, the sealant application area is determined within the sealing surface (sealing band); and because the key factor for the sealant to play a role is the existence of fastening force, the sealant application route between two bolt holes is determined as the connection line of the two bolt holes (because each position on this route is the position of the maximum stress generated by the maximum pre-tightening force, which is most conducive to the sealant fitting tightly); considering that the sealant will turn into a glue film and spread outwards during extrusion, in order to ensure that the sealant does not spread beyond the sealing surface and cause pollution, within the diameter range of the threaded hole, the position of the sealant application is at the 1 / 2 position of the distance between the threaded hole and the inner edge of the joint surface, as Figure 3 shown, which is a case diagram of the sealant application position and route.

[0073] Among them, in step 2, when the distribution route of the fasteners is not a straight line (for example, a 90-degree angle), then the intersection route of its distribution direction is used as the sealant application route; if the fasteners are distributed in a circle, the sealant application route is along the arc route on the pitch circle of the fasteners;

[0074] Let the distance between the bolt hole and the inner edge be x, then the distance from the sealant application position to the inner edge should be x / 2; let the radius of the threaded hole be r, then the diameter of the arc route for applying sealant along the periphery of the threaded hole should be: R = r + x / 2;

[0075] Therefore, the method for determining the sealant application route is:

[0076] (1) The diameter of the arc route for applying sealant around the bolt hole is: R = r + x / 2;

[0077] (2) The straight line route for applying sealant at the position without bolt holes is the connection line of the bolt hole centers;

[0078] (3) The intersection point where the arc route specified in (1) and the straight line route specified in (2) meet is the turning point of the sealant application route.

[0079] Among them, in step 4, calculate the diameter of the sealant column;

[0080] The sealant is generally stored in a sealed plastic tube. Before use, a circular small hole needs to be cut at the head of the plastic tube, and the sealant is extruded from the plastic tube by using a special tooling. Therefore, the extruded sealant is cylindrical, called a glue column. Obviously, the diameter of the glue column determines the amount of sealant used. To accurately control the amount of glue applied, only the diameter of the glue column needs to be accurately calculated, that is, the diameter of the circular small hole cut in the plastic tube;

[0081] Step 4 includes the following sub-steps:

[0082] Step 41: Determine the form and position tolerance of the joint surface;

[0083] Step 42: Calculate the maximum clearance of the joint surface;

[0084] Step 43: Calculate the thickness of the glue film;

[0085] Step 44: Determine the width of the sealing surface;

[0086] Step 45: Calculate the diameter of the glue column;

[0087] Step 46: Control of the glue outlet hole.

[0088] Among them, in the said Step 41, determine the form and position tolerance of the joint surface;

[0089] Suppose the end faces of two components jointly form the joint surface, which are plane A and plane B respectively. The flatness of plane A is a (mm), and the flatness of plane B is b (mm).

[0090] Among them, in the said Step 42, calculate the maximum clearance of the joint surface;

[0091] When the maximum protruding or recessed positions of plane A and plane B exactly coincide at the same position, the joint surface obtains the maximum clearance at this position or the maximum protruding point makes other positions obtain the maximum clearance. Therefore, calculate the maximum clearance h = a + b.

[0092] Among them, in the said Step 43, calculate the thickness of the glue film;

[0093] The sealant fully fills the gap of the joint surface; considering that when the sealant solidifies from liquid to solid, its volume shrinkage coefficient α is 0.9 - 1.0, so the thickness of the glue film δ = h / α = (a + b) / α.

[0094] Among them, in the said Step 44, determine the width of the sealing surface;

[0095] As Figure 2 shown, define the width of the sealing surface as l (mm);

[0096] The width of the joint surface is L, and the diameter of the bolt hole is D;

[0097] Step 45: Calculate the diameter of the sealant column;

[0098] According to the principle that the volume of the sealant remains unchanged during the extrusion deformation process, assuming the diameter of the sealant column is d and the length of the column is s, the volume of the sealant column is After the sealant column is extruded into a sealant film, the volume V2 = δ × l × s. Since V1 = V2, we can obtain The solution is:

[0099] Among them, in the above step 46, the control of the glue outlet;

[0100] It is very difficult to cut a diameter d at the glue outlet of the plastic bottle of the glue application tool with scissors. A reaming tool with a diameter of d can be pre-processed on a lathe and used to ream the glue outlet of the plastic bottle, which is easier to ensure that the glue output reaches the expected target.

[0101] The patent protection scope and key points of the present invention

[0102] (1) The present invention proposes a method for using a sealant to fill the gap of the joint surface to achieve sealing. The sealant is a glue-like substance in an approximate liquid state and can be called a solid after curing. Other similar sealants, seasonings, etc., although not called sealants, have no essential difference from the sealant described in the present invention in essence, so they should be within the protection scope of the present invention.

[0103] (2) The method of dividing the sealing surface (sealing band) on the joint surface proposed by the present invention is considered based on the fact that the bolt hole does not have a sealing function and the stress distribution characteristics after bolt pre-tightening. Its purpose is to ensure reliable sealing and prevent the sealant from being extruded from the bolt hole. During the actual use process, a certain adjustment range is allowed. The present invention only gives the implementation case with the best effect. Therefore, fine-tuning based on the method of dividing the sealing band described in this patent does not change the essence of the solution described in the present invention, so it is still within the protection scope of the present invention.

[0104] (3) The glue application position and route described in the present invention are the best cases to achieve good sealing and reduce the extrusion of the sealant from the joint surface. Fine-tuning on this basis, for example, changing the position from 1 / 2 to 3 / 5, etc., does not change the essential solution of the present invention, so it is still within the protection scope of the present invention.

[0105] (4) The method for calculating the diameter of the sealant column described in the present invention, the core key point is based on the need to compensate for the joint surface gap and the principle that the volume of the sealant remains unchanged before and after extrusion. Therefore, when the sealant changes from a circular shape to an oval, rectangular, triangular, etc. shape at the outlet of the plastic pipe, it does not change the essence of the present invention and should also be within the protection scope of the present invention.

[0106] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A method for applying glue to the joint surface of an end-face connection sealing structure, characterized in that, The method includes: Step 1: Divide the sealing surface; Step 2: Determine the application route and position of the sealant; Step 3: Calculate the diameter of the sealant column.

2. The method for applying glue to the joint surface of the end face connection sealing structure according to claim 1, characterized in that, In the said Step 1, divide the sealing surface; The basic principle of the sealant to achieve sealing is that the sealant compensates for the gap generated between two components at the joint surface due to manufacturing errors. For the sealant to function, it relies on fasteners to closely fit the two components and the sealant together through pre-tightening force. Therefore, any place with an external leakage channel belongs to the ineffective sealing area, defined as the non-sealing surface, and only the sealing surface needs to be coated with glue; the joint surface is divided into the sealing surface and the non-sealing surface. In the area outside the threaded hole, when the internal medium of the product moves from the inside to the bolt hole, it can leak through the bolt hole. Therefore, the area outside the bolt hole belongs to the non-sealing area.

3. The method for applying glue to the joint surface of the end face connection sealing structure according to claim 2, characterized in that, In the said Step 2, determine the application route and position of the sealant; The sealant application area is determined within the sealing surface; the application route between two bolt holes is determined as the connection line between the two bolt holes; within the diameter range of the threaded hole, the application position of the sealant is at the 1 / 2 position along the distance between the threaded hole and the inner edge of the joint surface.

4. The method for applying glue to the joint surface of the end face connection sealing structure according to claim 3, characterized in that, In the said Step 2, when the distribution route of the fasteners is not a straight line, then the intersection route of its distribution direction is used as the application route; If the fasteners are distributed in a circular shape, then the sealant application route is along the circular arc route on the pitch circle of the fasteners; Let the distance between the bolt hole and the inner edge be x, then the application position from the inner edge should be x / 2; let the radius of the threaded hole be r, then the diameter of the circular arc application route along the periphery of the threaded hole should be: R = r + x / 2; Therefore, the method for determining the application route is: (1) The diameter of the circular arc application route around the bolt hole is: R = r + x / 2; (2) The straight application route at the position without bolt holes is the connection line of the bolt hole centers; (3) The intersection point where the circular arc route specified in (1) and the straight line route specified in (2) meet is the turning point of the application route.

5. The method for applying glue to the joint surface of the end face connection sealing structure according to claim 4, characterized in that, In the said Step 4, calculate the diameter of the sealant column; The said Step 4 includes the following sub-steps: Step 41: Determine the form and position tolerance of the joint surface; Step 42: Calculate the maximum gap of the joint surface; Step 43: Calculate the thickness of the glue film; Step 44: Determine the width of the sealing surface; Step 45: Calculate the diameter of the glue column; Step 46: Control of the glue outlet hole.

6. The method for applying glue to the joint surface of the end face connection sealing structure according to claim 5, characterized in that, In the said Step 41, determine the form and position tolerance of the joint surface; Let the end faces of two components jointly form the joint surface, which are Plane A and Plane B respectively. Among them, the flatness of Plane A is a, and the flatness of Plane B is b.

7. The method for applying glue to the joint surface of the end face connection sealing structure according to claim 6, characterized in that, In the said Step 42, calculate the maximum gap of the joint surface; When the maximum protruding or recessed positions of Plane A and Plane B exactly coincide at the same position, the joint surface obtains the maximum gap at this position or the maximum protruding point, causing the maximum gap at other positions. Therefore, calculate the maximum gap h = a + b.

8. The method for applying glue to the joint surface of the end face connection sealing structure according to claim 6, characterized in that, In the said Step 43, calculate the thickness of the glue film; The sealant fully fills the gap of the joint surface; considering that when the sealant solidifies from liquid to solid, its volume shrinkage coefficient α is 0.9 - 1.0, so the thickness of the glue film δ = h / α = (a + b) / α.

9. The method for applying glue to the joint surface of the end face connection sealing structure according to claim 8, characterized in that, In the said Step 44, determine the width of the sealing surface; Define the width of the sealing surface as l; The width of the joint surface is L, and the diameter of the bolt hole is D; Step 45: Calculate the diameter of the glue column; According to the principle that the volume of the sealant remains unchanged during the extrusion deformation process, assuming the diameter of the sealant column is d and the length of the column is s, the volume of the column is After the column is extruded into a film, the volume V2 = δ×l×s. Since V1 = V2, we can obtain The solution is:

10. The method for applying glue to the joint surface of the end face connection sealing structure according to claim 9, characterized in that, In the said Step 46, the control of the glue outlet hole; Pre-process a reaming tool on a lathe, with its diameter being d. Use this reaming tool to ream the glue outlet of the plastic bottle, which can easily ensure that the glue output reaches the expected target.

Images