A kind of metal structure crack stop hole cold expansion device and method

Abstract

The present invention discloses a device and method for cold expansion of crack-stopping holes in metal structures. The hole expansion device is composed of a core rod, a bushing, an outer cylinder, a nose cover, a sealing cover, a buffer, a hydraulic press, a top cover and a bottom cover. The bushing is placed in the hole, and the thrust generated by the hydraulic press is used to pull the core rod back, thereby cold expanding the crack-stopping hole on the metal structure to obtain a cold-expanded hole. The cold-expanded hole made by the present invention can effectively prevent the expansion of cracks in the metal structure, and the construction is convenient, the process is simple, safe and reliable, the equipment has low power, and it saves materials and energy. The use of the bushing can prevent damage to the crack-stopping hole, and it is suitable for crack arrest of metal structure cracks with holes of various thicknesses and diameters. The core rod can be replaced for use with crack-stopping holes of different sizes or different expansion rates. It has high flexibility, good quality and excellent performance.

Description

Technical Field

[0001] The invention relates to the technical field of metal structures, and in particular to a device and a method for cold expansion of crack-stopping holes in metal structures. Background Art

[0002] Metal structures are widely used in modern engineering structures such as ships, bridges, etc. due to their advantages of light weight, high strength and high degree of industrial assembly. Most of these metal structures are made up of many individual steel components connected by a combination of bolts, rivets and welds. The most common problems at these connections or joints are corrosion and cracking or a combination of the two.

[0003] One of the major problems with metal structures is that they are susceptible to fatigue cracking. For example, cracking in steel bridges is primarily caused by localized material fatigue failure damage. When cars or trains pass over the bridge, the bridge components are subjected to variable cyclic loads. Over time, cracks may initiate at points of high stress concentration such as holes, structural details, gusset fillet radii, weld defects or corrosion pits. Depending on the applied load or stress, the frequency of the load cycles and the magnitude of the stress concentration, these cracks will continue to grow over time. If fatigue cracks are allowed to propagate and reach a critical crack length, fracture may occur, resulting in structural failure of the component or collapse of the entire structure. At the very least, these cracks will compromise the integrity of the structure and / or endanger the safety of people using the bridge. Catastrophic failure of bridge components will result in the possible closure of the bridge and cause major disruption to travel and local commercial infrastructure.

[0004] When cracks appear in metal structures due to fatigue, reinforcement often has higher economic value than replacement. Common reinforcement methods include CFRP reinforcement, bolted / welded steel plate reinforcement, bonded steel reinforcement, drilling crack arrest, and cold expansion crack arrest. Among them, for the CFRP reinforcement method for reinforcing metal plates, although the CFRP plate has high strength, its reinforcement effect is too dependent on epoxy adhesives, and the mechanical properties of epoxy adhesives are greatly affected by temperature. Temperature increases can easily lead to reduced reinforcement performance. In addition, if prestressing is applied, the construction process is also cumbersome. The bolted / welded steel plate reinforcement method and the bonded steel reinforcement method require welding on the parent material, which will cause the material to harden, and there is a risk of damaging the parent material, which will produce potential fatigue vulnerable points. Drilling crack arrest is one of the commonly used fatigue reinforcement methods for metal structures, but it is often a temporary reinforcement method that can only prevent crack growth in a short period of time. The cold expansion crack arrest hole method is a new crack arrest method. The cold expansion crack stop hole method is based on the drilling crack stop method. The crack stop hole is enlarged to apply residual compressive stress around it to protect it from fatigue load. The residual stress zone around the crack stop hole greatly reduces or prevents the expansion of cracks, and the fatigue resistance is about 10 times higher than that of the traditional drilling crack stop hole method.

[0005] Therefore, the cold expansion crack arrest method is a new and effective reinforcement method. However, there is currently a lack of professional crack arrest hole expansion equipment in China, and this excellent crack arrest method has not been used and promoted professionally and effectively.

[0006] Most people use hammered steel bolts to create cold expanded crack stops, but this method has the following disadvantages:

[0007] 1) It will damage the hole wall and weaken the effect of the residual stress zone;

[0008] 2) Since hammering is an impact load, it is not stable during the hole expansion process, and the hole diameter after hole expansion is not necessarily the target hole diameter;

[0009] 3) The direction of the steel bolt is easily changed during the hammering process, causing the steel bolt to deviate from the axis of the circular hole, resulting in an eccentric shape of the circular hole after expansion and uneven residual stress around the hole. Summary of the invention

[0010] The purpose of the present invention is to provide a device and method for cold expansion of crack-stopping holes in metal structures to solve the problems existing in the above-mentioned prior art.

[0011] To achieve the above-mentioned object, the present invention provides the following solutions: The present invention provides a metal structure crack stop hole cold expansion device, which is used to cold expand the crack stop hole on the metal plate to obtain the cold expanded hole, comprising a cold expansion mechanism and a driving mechanism, wherein the cold expansion mechanism is fixedly connected to the driving mechanism;

[0012] The cold expansion mechanism comprises an outer cylinder, a nose cover is provided on one side of the outer cylinder, and a sealing cover is provided on the other side, a protection mechanism is detachably connected to the nose cover, and when the crack stop hole is cold expanded, the protection mechanism passes through the crack stop hole to protect the hole wall of the crack stop hole, and the inner side of the protection mechanism is lubricated; a core rod passes through the protection mechanism and the nose cover, and a contraction drive structure is detachably installed on one side of the core rod, and the other side of the core rod passes through the crack stop hole, and when the contraction drive structure retracts, the core rod is driven to cold expand the crack stop hole; the contraction drive structure is electrically connected to the drive mechanism, a buffer mechanism is provided on the sealing cover, and the buffer mechanism is located in the outer cylinder for buffering and protecting the contraction drive structure;

[0013] The contraction drive structure and the drive mechanism are electrically connected to a control panel.

[0014] Preferably, the protection mechanism is a bushing, the bushing includes a plug-in portion and a connecting portion, and the plug-in portion and the connecting portion are an integrally formed structure, the plug-in portion is configured to conform to the crack-stop hole, and the connecting portion is configured to conform to the nose cover.

[0015] Preferably, the connecting portion is a funnel-shaped opening structure.

[0016] Preferably, the contraction drive structure includes a bottom cover arranged on the inner side of the outer cylinder, one end of a plurality of hydraulic presses is fixedly connected to the bottom cover, the other end of the hydraulic press is fixedly connected to a top cover, and the top cover is in sliding contact with the inner wall of the outer cylinder, the side of the core rod away from the crack stop hole is detachably connected to the top cover, and the hydraulic press is electrically connected to the drive mechanism.

[0017] Preferably, the buffer mechanism is a buffer.

[0018] Preferably, the driving mechanism is a hydraulic driving device, and the hydraulic driving device is electrically connected to the control panel through electric wires.

[0019] Preferably, the mandrel is a variable diameter high-strength steel rod, and the diameter transition region of the mandrel is smooth, and the angle of the diameter transition region of the mandrel is 15°-45°.

[0020] To achieve the above object, the present invention further provides the following solution: The present invention also provides a method for cold expansion of crack-stopping holes in a metal structure, using the cold expansion device for crack-stopping holes in a metal structure as shown in claim 1, wherein the steps of the cold expansion method are:

[0021] Drilling crack-stop holes: drilling crack-stop holes on the metal plate, determining the hole positions and basic shapes of the crack-stop holes, drilling holes to correct the size of the crack-stop holes, and verifying the size of the crack-stop holes;

[0022] Inspection before cold expansion: Check whether the diameter of the mandrel is within the tolerance range, lubricate the inner wall of the protection mechanism, and insert the mandrel into the protection mechanism;

[0023] Cold expansion and hole expansion: inserting the mandrel and the protection mechanism into the crack-stopping hole, retracting the mandrel through the contraction drive structure to expand the hole, retracting the mandrel into the nose cover to form a cold expansion hole, and removing the protection mechanism from the cold expansion hole and recovering it;

[0024] Inspection: Check whether the diameter of the cold-expanded hole after expansion meets the requirements. If not, repeat the above operation until the diameter of the cold-expanded hole after expansion meets the requirements.

[0025] The present invention discloses the following technical effects: The metal structure crack stop hole cold expansion device disclosed in the present invention has the following technical effects:

[0026] 1. The use of the protection mechanism disclosed in the present invention can protect the crack stop hole, prevent eccentricity during cold expansion, ensure radial expansion of the crack stop hole, make the expansion of the crack stop hole uniform, and minimize the axial displacement of the material. It is suitable for crack arrest of metal plates with holes of various thicknesses and diameters. At the same time, the inner cavity of the protection mechanism is lubricated to reduce the pulling force required when the core rod is pulled back, making hole expansion easier.

[0027] 2. The combined use of the protection mechanism, the core rod and the contraction drive structure of the present invention can increase the fatigue life of the corresponding crack-stopping hole, usually by 3 to 10 times, and can prevent the growth of small cracks in the hole;

[0028] 3. The present invention reduces the axial displacement of the crack stop hole to the maximum extent by fixing the mandrel. At the same time, the mandrel can be replaced for use with crack stop holes of different sizes or different hole expansion rates, with high flexibility, good quality and excellent performance;

[0029] 4. The hole expansion equipment of the present invention has low construction cost and reduces maintenance and inspection costs. It is simple and easy to use, single-sided operation, and convenient construction. It has a wide range of applications and can be used for civil metal structures as well as aerospace metals, including aluminum alloys, titanium, and high-strength steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0031] Figure 1 It is a schematic plan view of the crack hole expansion device of the present invention;

[0032] Figure 2 A three-dimensional schematic diagram of the crack expansion device of the present invention;

[0033] Figure 3 It is a structural schematic diagram of a specific implementation of the crack hole expansion device of the present invention;

[0034] Figure 4 for Figure 3 Schematic diagram of the internal structure;

[0035] Figure 5 It is a three-dimensional schematic diagram of a specific embodiment of the crack hole expansion device of the present invention;

[0036] Among them, 1-core rod; 2-bushing; 3-nose cover; 4-outer cylinder; 5-sealing cover; 6-buffer; 7-top cover; 8-hydraulic valve; 9-bottom cover; 10-metal plate; 11-crack stop hole; 12-crack; 13-hydraulic drive device. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] Embodiment 1

[0040] Reference Figure 1-5 The present invention provides a metal structure crack stop hole cold expansion device, which is used for cold expanding the aperture of the crack stop hole 11 on the metal plate 10 to obtain the cold expanded hole, comprising a cold expansion mechanism and a driving mechanism, the cold expansion mechanism and the driving mechanism are fixedly connected, wherein the driving mechanism is a hydraulic driving device 13, the hydraulic driving device 13 is electrically connected to the control panel through wires, and the hydraulic driving device 13 can be a hydraulic press;

[0041] The cold expansion mechanism includes an outer tube 4, and a nose cover 3 is arranged on one side of the outer tube 4, wherein the outer tube 4 and the nose cover 3 can be connected by a threaded connection; a sealing cover 5 is arranged on the other side, and the connection between the sealing cover 5 and the outer tube 4 can be threaded or detachably connected by screws; a protective mechanism is detachably connected to the nose cover 3, and when the crack stop hole 11 is cold expanded, the protective mechanism passes through the crack stop hole 11 to protect the hole wall of the crack stop hole 11 to prevent the problem of eccentricity in its direction during cold expansion, thereby ensuring that the residual stress around the crack stop hole is more uniform; and the inner side of the protective mechanism is lubricated; a core rod 1 passes through the protective mechanism and the nose cover 3, and one side of the core rod 1 can be detachably installed A contraction drive structure is provided, wherein the mandrel 1 can be fixedly installed on the contraction drive structure by screws; the other side of the mandrel 1 passes through the crack stop hole 11, and when the contraction drive structure retracts, the mandrel 1 is driven to cold expand the crack stop hole 11; the contraction drive structure and the drive mechanism are electrically connected, a buffer mechanism is provided on the sealing cover 5, and the buffer mechanism is located in the outer cylinder 4, which is used to buffer and protect the contraction drive structure, wherein the buffer mechanism is a buffer 6, the mandrel 1 is a variable diameter high-strength steel rod, and the diameter transition area of ​​the mandrel 1 is smooth, the diameter transition area angle of the mandrel 1 is 15°-45°, the surface of the steel rod is a smooth surface, and a protrusion is provided at the front end of the mandrel 1 for hole expansion;

[0042] The contraction drive structure and the drive mechanism are electrically connected to a control panel (not shown in the figure); the control panel is a control panel of an electric control box, and the movement of the contraction drive structure and the drive mechanism can be controlled by electric control.

[0043] When a crack 12 appears on the metal structure, i.e., the metal plate 10, a drill bit can be used to drill a hole at the very end of the crack 12, i.e., the crack stop hole 11. When the crack stop hole 11 needs to be enlarged, first, the core rod 1 is selected according to the specifications of the crack stop hole 11. When the specifications of the core rod 1 are determined, the core rod 1 is inserted into the protective mechanism. Then, the core rod 1 is inserted into the protective mechanism. At this time, the electrical control box is powered on, and the control panel is controlled to start the driving mechanism, i.e., under the action of the driving mechanism, the core rod 1 and the protective mechanism can be inserted into the crack stop hole 11. Then the staff controls the control panel to start the contraction driving structure, so that it drives the core rod 1 to retract, thereby achieving the purpose of expanding the aperture of the crack stop hole 11. The present application fixes the core rod 1 so that when the core rod 1 retracts, it mainly produces a radial position, which can minimize the axial displacement of the hole, and at the same time The interior of the protection mechanism is lubricated to provide a dry film lubricating medium for the core rod 1, reducing the pulling force required when the core rod 1 is pulled back, making hole expansion easier. Since the protection mechanism is directly inserted into the crack stop hole 11, when the core rod 1 passes through the crack stop hole 11, the outer edge is controlled so that the aperture expansion does not occur, ensuring the aperture expansion, playing a protective role, and making the hole expansion uniform, thereby increasing the fatigue life of the corresponding crack stop hole 11, usually increasing the fatigue life of the crack stop hole 11 by 3 to 10 times, and preventing the growth of small cracks 12 in the crack hole 11; in addition, the metal structure crack stop hole 11 cold expansion equipment disclosed in the present application is simple and easy to use, single-sided operation, convenient construction, low construction cost, reduced maintenance and inspection costs, and at the same time, has a wide range of applications, and can be applied to civil metal structures, and can also be used for aerospace metals, including aluminum alloys, titanium and high-strength steel.

[0044] According to a further optimization scheme, the protective mechanism is a bushing 2, wherein the bushing 2 is not only for protection but also essential for hole expansion: the bushing 2 should be a flexible metal, and the hole is expanded by making the core rod 1 squeeze the bushing 2; the bushing 2 includes a plug-in portion and a connecting portion, and the plug-in portion and the connecting portion are an integrally formed structure, the plug-in portion is arranged in the shape of the crack stop hole 11, and the connecting portion is arranged in the shape of the nose cover 3. And the connecting part is a funnel-shaped opening structure; the plug-in part is a cylindrical structure. When in use, the plug-in part of the cylindrical structure will be directly inserted into the crack stop hole 11 under the push of the hydraulic press, and the outer wall of the plug-in part will abut against the inside of the crack stop hole 11. Lubricating oil is applied to the inner wall of the bushing 2. Lubricating oil is used to reduce the tension of the core rod 1, ensure the uniform radial expansion of the drill stopper (not shown in the figure), and allow single-sided processing; the use of the bushing can prevent damage to the hole, provide a dry film lubrication medium for the core rod, ensure the radial expansion of the hole, and minimize the axial displacement of the material. It is suitable for crack stopping of metal plates 10 with holes of various thicknesses and diameters. The core rod can be replaced for use with crack stop holes of different sizes or different expansion rates. It has high flexibility, good quality and excellent performance.

[0045] A further optimized solution is that the contraction drive structure includes a bottom cover 9 arranged on the inner side of the outer tube 4, wherein the bottom cover 9 can be screwed and fixed on the inner side of the outer tube 4 by means of a threaded connection, or can be directly fixed to the inner side of the outer tube 4 by means of an integral molding mechanism; one end of a plurality of hydraulic cylinders 8 is fixedly connected to the bottom cover 9, and the other end of the hydraulic cylinder 8 is fixedly connected to a top cover 7, and the top cover 7 is in sliding contact with the inner wall of the outer tube 4, and the side of the core rod 1 away from the crack stop hole 11 can be detachably mounted on the top cover 7, wherein the connection method thereof can be a bolt connection or a snap-on type to adapt to crack stop holes with different apertures and different requirements for hole expansion. The hydraulic press 8 is electrically connected to the driving mechanism. Starting the hydraulic press 8 to retract can drive the core rod 1 to retract, thereby realizing the cold expansion and expansion of the crack stop hole 11. The cold expansion of the crack stop hole 11 offsets its fatigue characteristics by generating a compressive residual stress field around the hole, effectively protecting the hole from the influence of the cyclic tensile stress load that causes the crack 12 to expand. At the same time, the core rod 1, the bushing 2 and the nose cover 3 are replaceable parts, which can be made of different materials or diameters according to actual conditions.

[0046] The present invention also provides a method for cold expansion of crack-stopping holes in a metal structure, using the cold expansion device for crack-stopping holes in a metal structure as shown in claim 1, wherein the steps of the cold expansion method are as follows:

[0047] Drilling crack stop holes: Drilling crack stop holes on the metal plate 10, aluminum plate or titanium plate, etc., determining the hole position and basic shape of the crack stop hole, drilling to correct the size of the crack stop hole, and verifying the size of the crack stop hole;

[0048] Inspection before cold expansion: Check whether the diameter of the mandrel 1 is within the tolerance range, lubricate the inner wall of the protection mechanism, and insert the mandrel 1 into the protection mechanism; specifically, apply lubricating oil on the inner wall of the bushing 2 and lubricate the inside thereof. Lubricating with lubricating oil reduces the tension of the mandrel 1, ensures uniform radial expansion of the drill stopper, and allows single-sided processing, and then the mandrel 1 is inserted through the bushing 2;

[0049] Cold expansion and reaming: insert the mandrel 1 and the protection mechanism into the crack stop hole, retract the mandrel 1 by contracting the driving structure to expand the hole, retract the mandrel 1 into the nose cover 3 to form a cold expansion hole, take out the protection mechanism from the cold expansion hole and recycle it; specifically, insert the mandrel 1 and the bushing 2 into the crack stop hole, start the hydraulic press 8 by controlling the control panel, make the hydraulic press 8 retract, and then drive the mandrel 1 to expand the crack stop hole 11, retract the mandrel 1 into the nose cover 3 to form a cold expansion hole, take out the bushing 2 from the cold expansion hole and recycle it, and the bushing 2 after use can be recycled to a designated place for centralized treatment;

[0050] Inspection: Check whether the diameter of the cold-expanded hole after expansion meets the requirements. If not, repeat the above operation until the diameter of the cold-expanded hole after expansion meets the requirements.

[0051] The cold hole expansion produced by the present invention can effectively prevent the expansion of the crack 12, and the construction is convenient, the process is simple, safe and reliable, the equipment power is low, and it saves materials and energy. The use of the bushing 2 can prevent damage caused by the hole, provide a dry film lubrication medium for the core rod 1, ensure the radial expansion of the hole, and minimize the axial displacement of the material. It is suitable for crack arresting of cracks 12 in metal plates 10 with holes of various thicknesses and diameters. The core rod 1 can be replaced for use with crack arresting holes 11 of different sizes or different hole expansion rates. It has high flexibility, good quality and excellent performance.

[0052] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0053] The above embodiments are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A metal structure crack stop hole cold expansion device, used for cold expanding a crack stop hole (11) on a metal plate (10) to obtain a cold expanded hole, characterized in that: It comprises a cold expansion mechanism and a driving mechanism, wherein the cold expansion mechanism is fixedly connected to the driving mechanism; The cold expansion mechanism comprises an outer cylinder (4), a nose cover (3) is provided on one side of the outer cylinder (4), and a sealing cover (5) is provided on the other side; a protection mechanism is detachably connected to the nose cover (3); when the crack stop hole (11) is cold expanded, the protection mechanism passes through the crack stop hole (11) to protect the hole wall of the crack stop hole (11), and the inner side of the protection mechanism is lubricated; a core rod (1) passes through the protection mechanism and the nose cover (3), and a contraction drive structure is detachably installed on one side of the core rod (1); the other side of the core rod (1) passes through the crack stop hole (11); when the contraction drive structure retracts, the core rod (1) is driven to cold expand the crack stop hole (11); the contraction drive structure is electrically connected to the drive mechanism, a buffer mechanism is provided on the sealing cover (5), and the buffer mechanism is located in the outer cylinder (4) and is used to provide buffer protection for the contraction drive structure; The contraction drive structure and the drive mechanism are electrically connected to a control panel; The protection mechanism is a bushing (2), the bushing (2) comprises a plug-in portion and a connecting portion, and the plug-in portion and the connecting portion are an integrally formed structure, the plug-in portion is arranged in a conformal relationship with the crack-stopping hole (11), and the connecting portion is arranged in a conformal relationship with the nose cover (3); the contraction drive structure comprises a bottom cover (9) arranged on the inner side of the outer cylinder (4), one end of a plurality of hydraulic machines (8) is fixedly connected to the bottom cover (9), the other end of the hydraulic machine (8) is fixedly connected to a top cover (7), and the top cover (7) is in sliding contact with the inner wall of the outer cylinder (4), the side of the core rod (1) away from the crack-stopping hole (11) is detachably connected to the top cover (7), and the hydraulic machine (8) is electrically connected to the drive mechanism.

2. The metal structure crack stop hole cold expansion equipment according to claim 1, characterized in that: The connecting portion is a funnel-shaped opening structure.

3. The metal structure crack stop hole cold expansion equipment according to claim 1, characterized in that: The buffer mechanism is a buffer (6).

4. The metal structure crack stop hole cold expansion equipment according to claim 1, characterized in that: The driving mechanism is a hydraulic driving device (13), and the hydraulic driving device (13) is electrically connected to the control panel via an electric wire.

5. The metal structure crack stop hole cold expansion equipment according to claim 1, characterized in that: The core rod (1) is a high-strength steel rod with a variable diameter, and the diameter transition region of the core rod (1) is smooth; the angle of the diameter transition region of the core rod (1) is 15°-45°.

6. A method for cold expansion of crack-stopping holes in metal structures, characterized in that: The cold expansion device for crack-stopping holes in metal structures as shown in claim 1 is used, and the steps of the cold expansion method are as follows: Drilling crack-stop holes: drilling crack-stop holes on the metal plate (10), determining the hole position and basic shape of the crack-stop holes, drilling holes to correct the size of the crack-stop holes, and verifying the size of the crack-stop holes; Inspection before cold expansion: checking whether the diameter of the mandrel (1) is within the tolerance range, lubricating the inner wall of the protection mechanism, and inserting the mandrel (1) into the protection mechanism; Cold expansion: inserting the mandrel (1) and the protective mechanism into the crack-stopping hole, retracting the mandrel (1) through the contraction drive structure to expand the hole, retracting the mandrel (1) into the nose cover (3) to form a cold expanded hole, and removing the protective mechanism from the cold expanded hole and recovering it; Inspection: Check whether the diameter of the cold-expanded hole meets the requirements. If not, repeat the above operation until the diameter of the cold-expanded hole meets the requirements.

Images