CN114770034A - Method and device for cutting stent pipe - Google Patents

Abstract

The present application provides a method and device for cutting a stent pipe, and the cutting method includes: sleeves a first pipe and a second pipe on both ends of a connecting piece respectively; pressurizing the connecting piece to make the connecting piece and the first pipe and the first pipe and The second pipe material forms a combined structure with interference fit; the combined structure is fixed, and the first pipe material and/or the second pipe material in the combined structure is cut. The method and device for cutting a stent pipe provided by the present application can evenly connect the first pipe and the second pipe by means of pressure expansion of the connector, which can effectively improve the utilization rate of the stent pipe and save production costs.

Description

Method and device for cutting stent pipe

technical field

The present application belongs to the technical field of medical devices, and in particular relates to a method and device for cutting a stent tube.

Background technique

The existing laser cutting machine for cutting bracket basically clamps the pipe first, and the protruding part extends to the laser cutting head, and there is a certain distance between the two parts (generally about 120mm), material tubing) cannot be used. Tubing used for high-end medical device products is often very expensive, such as tubing used for heart valve stents, and the waste of tailings increases production costs. In addition, conventional welded butt joints or glued butt joints will cause problems such as pipe deformation and poor coaxiality, and heating and degumming will affect the mechanical properties of the pipes, which will lead to the cut brackets that are not cut through, the waveform is uneven, and the mechanical properties are not up to standard. In other cases, stents in these conditions are substandard products and cannot be used clinically.

SUMMARY OF THE INVENTION

In view of the above technical problems, the present application provides a method and device for cutting a stent pipe, which can evenly connect the first pipe and the second pipe by means of pressure expansion of the connector, which can effectively improve the utilization rate of the stent pipe and save production costs. .

The application provides a method for cutting a stent pipe, comprising:

The first pipe material and the second pipe material are respectively sleeved on both ends of the connecting piece;

Pressurizing the connecting piece, so that the connecting piece, the first pipe material and the second pipe material form a combined structure of interference fit;

The combined structure is fixed, and the first pipe material and/or the second pipe material in the combined structure is cut.

Optionally, the first pipe material, the second pipe material and the connecting piece are located on the same axis.

Optionally, the described sleeves of the first pipe material and the second pipe material on both ends of the connector respectively include:

determining the centerline of the connector;

One end of the first pipe material and one end of the second pipe material are respectively passed through the two ends of the connecting piece and aligned along the center line.

Optionally, the pressurizing the connector includes:

The connector is pressurized by at least one of pneumatic pressurization, hydraulic pressurization, and extrusion.

Optionally, the pressurizing the connector further comprises:

The connecting piece is connected with a pressurizing device for pressurizing the connecting piece by means of a quick-change fitting.

Optionally, the method further includes:

When the length of the first pipe material and/or the second pipe material is less than or equal to a preset value, the pressure of the connecting piece is released.

Optionally, the fixing of the combined structure and cutting the first pipe material and/or the second pipe material in the combined structure include:

The combined structure is fixed on the fixture of the laser cutting machine, and the first pipe material and/or the second pipe material is cut by the laser cutter head.

The present application also provides a device for cutting a stent pipe, using the above method for cutting a stent pipe, the cutting device includes a connector, a first pipe, a second pipe, and a cutting device;

The connecting piece has a cylindrical hollow structure;

The inner diameter of the first pipe material is larger than the outer diameter of the connecting piece, and the inner diameter of the second pipe material is larger than the outer diameter of the connecting piece;

The cutting device includes a fixing part and a cutting part.

Optionally, the hardness of the connecting piece is less than or equal to the hardness of the first pipe material, and the hardness of the connecting piece is less than or equal to the hardness of the second pipe material.

Optionally, the inner diameter of the first pipe material is equal to the inner diameter of the second pipe material.

The method and device for cutting a stent pipe provided by the present application, and the cutting method include: sleeves a first pipe and a second pipe on both ends of a connecting piece respectively; pressurizing the connecting piece to make the connecting piece and the first pipe and the second pipe The two pipes form a combined structure with interference fit; the combined structure is fixed, and the first pipe and/or the second pipe in the combined structure is cut. The method and device for cutting a stent pipe provided by the present application can evenly connect the first pipe and the second pipe by means of pressure expansion of the connector, which can effectively improve the utilization rate of the stent pipe and save production costs.

Description of drawings

Fig. 1 is the schematic flow chart of the cutting method of the stent pipe material provided in the embodiment of the present application;

Fig. 2 is one of the process schematic diagrams of the cutting method of the stent pipe provided by the embodiment of the present application;

3 is the second schematic diagram of the cutting method of the stent pipe provided by the embodiment of the present application;

FIG. 4 is the third schematic diagram of the process of the cutting method of the stent tube provided by the embodiment of the present application.

Detailed ways

The technical solutions of the present application will be further elaborated below with reference to the accompanying drawings and specific embodiments of the description. Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used herein in the specification of the application are for the purpose of describing specific embodiments only, and are not intended to limit the application. As used herein, "and/or" includes any and all combinations of one or more of the associated listed items.

first embodiment

FIG. 1 is a schematic flowchart of a method for cutting a stent tube provided by an embodiment of the present application. Referring to FIG. 1, the present embodiment provides a method for cutting a stent pipe, including the following steps:

Step 201 : sleeve the first pipe material and the second pipe material on both ends of the connector respectively.

Please refer to FIG. 2 , for example, the first pipe material is the tail material pipe material 1 and the second pipe material is the new pipe material 3 . First, make a connecting piece 2 with a length of about 20mm. The outer circle of the connecting piece 2 is assembled with the tail material pipe 1 and the new pipe material 3 by half according to the corresponding grade and tolerance. The end of the tail material pipe 1 and the end of the new pipe material 3 are assembled. Head aligned. Wherein, the inner diameter of the tail stock pipe material 1 is larger than the outer diameter of the connecting piece 2 , and the inner diameter of the new pipe material 3 is larger than the outer diameter of the connecting piece 2 . Optionally, the difference between the outer diameter of the connecting piece 2 and the inner diameter of the tail material pipe material 1 and the new pipe material 3 is between 0.05mm-0.10mm. The connecting piece 2 is coaxially connected with the tail material pipe material 1 and the new pipe material 3, so that the tail material pipe material 1, the new pipe material 3 and the connecting piece 2 are located on the same axis.

Optionally, the inner diameter of the tailstock pipe material 1 and the inner diameter of the new pipe material 3 are equal, so that the tailstock pipe material 1 and the new pipe material 3 can be synchronously and uniformly deformed with the expansion of the connector 2 .

Optionally, the first pipe material and the second pipe material are respectively sleeved on both ends of the connector, including:

Determine the center line of the connector;

One end of the first pipe material and one end of the second pipe material are respectively passed through the two ends of the connecting piece and aligned along the center line.

Specifically, a mark can be made at the midpoint of the connector 2 along the length direction, and half of the connector 2 is inserted into the tail material pipe 1, and the other half is inserted into the new pipe material 3, so that the tail material pipe 1 and the second pipe material 2 each occupy half the length of the connector 2.

Step 202 : pressurizing the connector to form a combined structure of interference fit between the connector, the first pipe material and the second pipe material.

Please refer to Fig. 3, the outer wall of the connecting piece expands outward after being pressed, and is in close contact with the tail material pipe 1 and the new pipe 3 respectively. The connecting piece 2 is evenly expanded by means of quantitative pressure, so that a certain degree of interference fit is formed between the tail stock pipe material 1, the new pipe material 3 and the connecting piece 2. At the same time, the connector 2 has good torsion resistance, which not only realizes the coaxial and positioning butt joint between the tailstock pipe and the new pipe, but also ensures sufficient torque requirements when cutting the pipe, and prevents the subsequent bracket cutting from being cut through or penetrating. uneven waveform. The cutting method of this embodiment does not use chemical adhesive, so as to prevent chemical adhesive from affecting the surface quality of the stent tube, and subsequent removal is difficult. If cleaning is not clean, the stent will be chemically toxic, which will bring hidden dangers to the subsequent implanted valve products.

Specifically, the connector 2 can be pressurized by at least one of air pressure, hydraulic pressure, and extrusion, so that the connector 2 can be expanded uniformly, and the physical and chemical properties of the stent tube can be kept stable. Wherein, the connecting piece 2 has a cylindrical hollow structure. One end of the connector 2 can be provided with an opening, and the small hole of the connector 2 and the quick-change joint 4 can be connected through a small tube or seamless steel pipe, which can be connected by thread or welding, and ensure good sealing. When only one end of the connector 2 is perforated, the perforated end of the connector 2 may be the end of the tailing material pipe 1 or the end of the new pipe material 3. When the new pipe is relatively long, you can choose to connect the quick-change joint 4 at one end of the tailstock pipe, so that the quick-change joint 4 is exposed at one end of the tailstock pipe, which is convenient for subsequent pressurization or pressure relief operations. If the space of the cutting device is insufficient, you can choose to connect the quick-change joint 4 to one end of the new pipe for pressure relief. Then connect the pressurized equipment through the quick-change joint, and inject gas or liquid into the connector 2 to make it pressurized and expanded. Of course, both ends of the connector 2 can also be directly squeezed to deform and expand.

Step 203: Fix the combined structure, and cut the first pipe material and/or the second pipe material in the combined structure.

Please refer to FIG. 3 , fix the combined structure of the tail material pipe 1 , the connector 2 and the new pipe material 3 on the fixture 5 of the laser cutting machine, and use the laser cutter head 6 to cut the tail material pipe 1 and/or the new pipe material 3 . Specifically, the connected composite structure is clamped on the fixture platform of the laser cutting machine, and the normal cutting operation is performed. When the length of the connecting piece 2 is 20 mm, the tail material pipe (the first pipe material 3) and the connecting piece 2 only have With a length of about 10mm, the final remaining length of the tailstock pipe will be reduced to the greatest extent, which greatly improves the utilization rate of the tailstock pipe.

Optionally, the cutting method, further comprising:

When the length of the first pipe material and/or the second pipe material is less than or equal to the preset value, the pressure of the connecting piece is released to separate the connecting piece, the first pipe material and the second pipe material.

In this embodiment, the length of the tailing pipe 1 and/or the new pipe 3 is less than or equal to the preset value, and the preset value can be set as the length of a finished stent, when the remaining length of the stent pipe is not enough to cut out a complete stent , the connecting piece 2 can be restored to its original form by releasing the pressure, and the tail material pipe 1, the new pipe 3 and the connecting piece 2 can be separated. This process does not require heating or cold shrinking of the stent tube, which avoids the change of the mechanical properties of the stent tube itself due to heating or cold shrinkage, thereby affecting the final quality of the stent. It should be noted that the pressure relief method should correspond to the pressure increase method in step 202 . For example, when the pressurization method is air pressure or hydraulic pressurization, the small hole of the connector 2 and the quick-change joint 4 can be connected through a small pipe or a seamless steel pipe, and then the pressure relief equipment is connected through the quick-change joint, so that the connector 2 is used in After the pressurized gas or liquid is discharged, the connector 2 is restored to its original shape. It should be understood that, in this embodiment, an integrated device for pressurization and pressure relief may be used to reduce the hardware devices involved in the processing process. Correspondingly, if pressing and deforming is adopted when pressurizing the connector 2 , the pressing force acting on the connector 2 can be removed.

Optionally, the hardness of the connecting piece is less than or equal to the hardness of the first pipe material, and the hardness of the connecting piece is less than or equal to the hardness of the second pipe material.

In this embodiment, the hardness of the material of the connector 2 is lower than the hardness of the bracket tube, and the difference is preferably above HB50, so as to avoid damage to the inner hole surface of the bracket tube.

It should be exemplified that the tailstock pipe material 1, the connecting piece 2 and the new pipe material 3 are injected into gas or liquid through the quick-change joint 4, so that the connecting piece 2 is evenly expanded, and the three are connected into one in the form of interference fit, and then The assembly is clamped on the fixture 5 of the laser cutting machine, and the normal production cutting is performed by the laser cutter head 6 . The specific operation steps are:

1. The initial outer diameter of the manufactured connector 2 should be smaller than the inner diameter of the bracket pipe (determined according to different types of pipes), and the length should be about 20mm. Mark the middle position of the connector 2 to ensure that the assembly lengths at both ends are equal; the connector One end of 2 is connected to the quick-change joint 4 through a small tube to ensure that the quick-change joint 4 is exposed to the other end of the tail material pipe 1 after assembly, which is convenient for subsequent pressurization or pressure relief operations.

2. Pre-assemble the tailings pipe 1, the connector 2 and the new pipe 3 according to the position shown in Figure 2. Use the quick-change joint 4 to connect the gas or liquid and control a certain pressure value. The state is combined as shown in Figure 3.

3. Clamp the assembly on the fixture 5 of the laser cutting machine, and carry out normal production cutting through the laser cutter head 6 . Because the middle line marking point of the connector 2 is exposed and visible to the naked eye, it can not only prevent the laser cutter head 6 from cutting to the position of the connector 2, but also judge whether the connection needs to be replaced according to the remaining length of the tail material pipe 1 and the required length of the bracket during cutting. Tail pipe 1 at one end of piece 2. Finally, when the remaining length of the tail material pipe 1 is not enough to cut a complete bracket, the pressure is released through the quick-change joint 4, so that the connector 2 is retracted to its original shape, and the tail material pipe material 1 is removed.

The invention realizes the reasonable butt joint of the tail material pipe material and the new pipe material, has high coaxiality, good torsion resistance and does not affect various properties of the pipe material, the connecting piece can be reused, the steps are few, and the operation is easy. It can achieve elastic and uniform expansion after pressurization, and return to its original shape after decompression.

The invention greatly improves the utilization rate of raw materials and saves the production cost. Usually the length of each pipe used for cutting the bracket is controlled below 1000mm, and the remaining length of each tailing pipe after normal cutting is generally about 120mm. By adopting the technological measures of the present invention, the length of the tailing pipe can be reduced to about 20mm, and can be increased by 10 mm. % or more pipe utilization.

The method and device for cutting a stent pipe according to the embodiments of the present application include: sleeves a first pipe and a second pipe on both ends of the connecting piece, respectively; pressurizing the connecting piece to make the connecting piece connect with the first pipe and the second pipe. forming a combined structure with interference fit; fixing the combined structure, and cutting the first pipe material and/or the second pipe material in the combined structure. The method and device for cutting a stent pipe provided in the embodiments of the present application uniformly connect the first pipe and the second pipe by means of pressure expansion of the connecting piece, which can effectively improve the utilization rate of the stent pipe and save production costs.

Second Embodiment

In this embodiment, the specifications of the tailing pipe material and the new pipe material selected from nickel-titanium alloy are both 8 mm in outer diameter and 0.5 mm in wall thickness. The specific operation steps are:

1. Make a copper alloy connector 2 with an outer diameter of 6.90-6.95mm, connect the connector and the quick-change joint through a small copper pipe or a seamless steel pipe, which can be connected by thread or welding, and ensure a good seal.

2. Pre-assemble nickel-titanium alloy tailstock pipes, connectors and new pipes;

3. Ventilate and pressurize the connector by 0.06MPa through the quick-change joint, check the interference fit of the three, and measure the outer diameter of the pipe with a vernier caliper or perform a slight torsion test to verify the interference.

4. Clamp the combination of the three on the fixture of the laser cutting machine, and carry out normal production cutting through the laser cutter head. Finally, when the remaining length of the tailing pipe is less than 20mm, the pressure is relieved through the quick-change joint, so that the connecting piece is retracted to its original shape, and the tailing pipe is removed.

Third Embodiment

In this embodiment, the specifications of the tailing pipe material and the new pipe material selected from cobalt-chromium alloy are both 29mm in outer diameter and 0.6mm in wall thickness. The specific operation steps are:

1. Make nylon connectors with an outer diameter of 27.70-27.75mm, connect the connectors and quick-change joints together through small copper pipes or seamless steel pipes, which can be connected in the form of threads or snaps, and ensure good sealing.

2. Cobalt-chromium alloy tailstock pipes, connectors and new pipes are pre-assembled;

3. Ventilate and pressurize the connector by 0.1MPa through the quick-change joint to check whether the three are in an interference fit. You can measure the outer diameter of the pipe with a vernier caliper or perform a slight torsion test to verify the interference.

4. Clamp the combination of the three on the fixture of the laser cutting machine, and carry out normal production cutting through the laser cutter head. Finally, when the remaining length of the tailing pipe is less than 20mm, the pressure is relieved through the quick-change joint, so that the connecting piece is retracted to its original shape, and the tailing pipe is removed.

Fourth Embodiment

This embodiment provides a device for cutting a stent tube, which applies the method for cutting a stent tube in any of the above embodiments.

The cutting device of the stent tube includes a connector, a first tube, a second tube and a cutting device;

The connecting piece has a cylindrical hollow structure, and at least one end of the connecting piece is provided with an opening;

The inner diameter of the first pipe material is larger than the outer diameter of the connecting piece, and the inner diameter of the second pipe material is larger than the outer diameter of the connecting piece;

The cutting device includes a fixing part and a cutting part.

Optionally, the hardness of the connecting piece is less than or equal to the hardness of the first pipe material, and the hardness of the connecting piece is less than or equal to the hardness of the second pipe material.

Optionally, the inner diameter of the first pipe material and the inner diameter of the second pipe material are equal.

Please refer to the first embodiment to the fourth embodiment for the specific application method of the stent pipe cutting device in this embodiment, which will not be repeated here.

The above-mentioned embodiments merely illustrate the principles and effects of the present application, but are not intended to limit the present application. Anyone skilled in the art can make modifications or changes to the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed in this application should still be covered by the claims of this application.

Claims (10)

1. a cutting method of a stent pipe material, is characterized in that, comprises: The first pipe material and the second pipe material are respectively sleeved on both ends of the connecting piece; Pressurizing the connecting piece, so that the connecting piece, the first pipe material and the second pipe material form a combined structure of interference fit; The combined structure is fixed, and the first pipe material and/or the second pipe material in the combined structure is cut. 2 . The cutting method according to claim 1 , wherein the first pipe material, the second pipe material and the connecting piece are located on the same axis. 3 . 3 . The cutting method according to claim 1 , wherein the sleeves of the first pipe material and the second pipe material on both ends of the connecting piece respectively comprise: 3 . determining the centerline of the connector; One end of the first pipe material and one end of the second pipe material are respectively passed through the two ends of the connecting piece and aligned along the center line. 4. The cutting method of claim 1, wherein the pressurizing the connector comprises: The connector is pressurized by at least one of pneumatic pressurization, hydraulic pressurization, and extrusion. 5. The cutting method of claim 4, wherein the pressurizing the connector further comprises: The connecting piece is connected with a pressurizing device for pressurizing the connecting piece by means of a quick-change fitting. 6. The cutting method of claim 1, wherein the method further comprises: When the length of the first pipe material and/or the second pipe material is less than or equal to a preset value, the pressure of the connecting piece is released. 7. The cutting method according to claim 1, wherein the fixing the combined structure and cutting the first pipe material and/or the second pipe material in the combined structure comprises: The combined structure is fixed on the fixture of the laser cutting machine, and the first pipe material and/or the second pipe material is cut by the laser cutter head. 8. A device for cutting a stent tube, characterized in that the method for cutting a stent tube according to any one of claims 1 to 7 is applied, the cutting device comprising a connector, a first tube, a second tube, and a cutting device; The connecting piece has a cylindrical hollow structure; The inner diameter of the first pipe material is larger than the outer diameter of the connecting piece, and the inner diameter of the second pipe material is larger than the outer diameter of the connecting piece; The cutting device includes a fixing part and a cutting part. 9 . The cutting device according to claim 8 , wherein the hardness of the connecting piece is less than or equal to the hardness of the first pipe material, and the hardness of the connecting piece is less than or equal to the hardness of the second pipe material. 10 . 10. The cutting device of claim 8, wherein the inner diameter of the first pipe material and the inner diameter of the second pipe material are equal.

Images