CN100402228C - Machining Technology of Platinum Alloy Tapered Nozzle - Google Patents

Abstract

The invention relates to a processing technology of a platinum alloy tapered leak nozzle, which belongs to the field of processing and manufacturing a glass fiber wire drawing bushing, and in particular relates to a processing technology of a drain nozzle of a platinum alloy bushing used for wire drawing of a tank kiln. The processing technology of platinum alloy tapered nozzle includes softening treatment process, cutting process, shaping process, reverse extrusion process, upsetting extrusion forming process and punching process. The bushing plate assembled with the tapered leak nozzle produced by the process of the present invention has a production cycle significantly lower than that of the bushing plate assembled with the leak nozzle produced by integral stamping and cutting, the platinum alloy processing loss is low, the use performance is stable, and the wire drawing is greatly improved. Operational production efficiency, high wire drawing output, and long service life of the bushing. The tapered leak nozzle leak plate produced by the invention has been widely used in the glass fiber drawing production of domestic tank kilns and ball kilns.

Description

Machining Technology of Platinum Alloy Tapered Nozzle

technical field

The invention relates to a processing technology of a platinum alloy tapered leak nozzle, which belongs to the field of processing and manufacturing a glass fiber wire drawing bushing, and in particular relates to a processing technology of a drain nozzle of a platinum alloy bushing used for wire drawing of a tank kiln.

Background technique

At present, there are two kinds of nozzle shapes of platinum alloy nozzles for glass fiber tank kiln wire drawing: cylindrical nozzle and conical nozzle. The cylindrical leak nozzle is cylindrical in shape. The inner wall of the tapered leak nozzle is cylindrical, and the outer part is conical, and the diameter of the mouth is smaller than the diameter of the root. Practice has proved that in the glass fiber tank kiln wire drawing production, compared with the cylindrical leak nozzle, the tapered leak nozzle has the advantages of good wire drawing cooling effect, no crystallization and overflow phenomenon, stable wire drawing operation, and high output. The wall thickness of the root is relatively thick, the structural strength is high, and the service life is improved, so it is recognized as the development direction of the current platinum alloy bushing for glass fiber tank kiln drawing.

In the bushing and bottom plate processing technology, the nozzle processing is the most important, and the quality of the nozzle processing is closely related to the service life of the bushing and the glass fiber drawing output. The drain plate leak nozzle for pool kiln wire drawing is made of expensive platinum-rhodium alloy; the number of leak nozzles is large, generally more than 800 holes; the leak nozzle aperture φd is small, φd=1.6-2.0 mm; the wall thickness b is relatively thin , wall thickness b=0.2~0.7 mm; the length L of the conical leak nozzle is short, L=5~6 mm; especially the conical leak nozzle, the cone angle α of the outer conical surface is small, α=8°, and the processing accuracy is extremely high, different The processing technology will affect the service life of the leak nozzle and the drawing output.

At present, there are two production processes for the production of platinum alloy tapered nozzles: one is the overall stamping process. That is, on the bottom plate of the platinum alloy bushing, the leak nozzle is directly punched and stretched by using the integral bushing die, and the nozzle and the board are integrated. The existing problems are: after stamping and stretching deformation of the platinum alloy bottom plate blank, the material of the nozzle part is obviously loose, the mechanical strength is also reduced, and the service life is greatly shortened; individual leakage nozzles often break and crack, directly causing the overall The bottom plate is scrapped, and the waste is serious. In addition, the overall stamping process is the whole plate or block stamping. Since the nozzles are arranged very closely on the bushing, the stamping die space for a single nozzle is very narrow, and the mold structure is small, resulting in a great pressure on the unit volume of the mold. The mold structure design, machining accuracy and material requirements are extremely high; moreover, the bushing mold has poor versatility, and it is difficult to meet the needs of leak nozzles with different sizes and different arrangements.

Another kind of leakage nozzle processing technology is to use CNC machine tool to turn hundreds or thousands of tapered leakage nozzles required for a bushing plate one by one. In addition to the fact that the metal cutting process will affect the strength and toughness of the leak nozzle, this processing method is also because its production efficiency is too low (only 3 to 4 pieces can be processed per minute), which is not convenient for mass production; , It is not easy to recycle, and the loss of expensive platinum alloy is as high as 1.5%, which makes the production cost too high.

Contents of the invention

In view of the above existing problems, the present invention proposes a cold heading process for platinum alloy conical leaky nozzles. It is based on the principle of metal plastic forming, puts the cold metal blank into the cavity of the mold installed on the press, and under the action of strong pressure and a certain forward speed, the metal blank is forced to perform one or more rounds in the cavity. Secondary extrusion upsetting, so as to obtain the required shape, size and extrusion with certain mechanical properties. The platinum alloy nozzle processed by this process has compact material and high strength; stable performance and long service life; the inner hole and skin of the platinum alloy scrap can be completely recycled, and the loss is low; at the same time, the processing cycle is short and the efficiency is high.

The formulation of cold heading processing technology needs to select a reasonable allowable deformation degree according to the material used. The greater the degree of allowable deformation, the fewer processes and the higher the productivity. However, the unit pressure must also increase, which may exceed the allowable unit pressure limit of the mold, resulting in damage to the mold. In view of the concrete situation that the leakage nozzle material to be processed is a platinum alloy material, according to the principle of constant volume and the law of minimum resistance, through calculation and test, the production process of the present invention is concluded to be carried out according to the following six steps:

The processing technology of platinum alloy conical leak nozzle includes softening treatment process, cutting process, shaping process, reverse extrusion process, upsetting extrusion forming process and punching process. The process steps and process conditions are as follows:

1. Softening process

The initial diameter of the billet ΦD1 is equal to the outer diameter of the mouth of the leak. Preparation of platinum alloy raw materials into

Annealing and softening treatment is carried out for the thin and long filament blank with an initial diameter of ΦD1;

2. Cutting process

According to the principle of constant volume of the leak nozzle, the initial length L1 of the leak nozzle blank is calculated, and the wire of the previous process is

The billet is fed through the feeding device, and cut off with a cutter when feeding the length L1;

3. Shaping process

The blank obtained from the cutting process is moved to the cavity of the die 2 of the pre-shaping die A on the press, and the pre-shaping is performed by the punch 1 of the pre-shaping die A; the cone after pre-shaping by the pre-shaping die A The semi-finished product of the shaped leak nozzle is ejected by the ejector pin 4 of the pre-shaping mold A, and then moved to the concave mold 2 cavity of the shaping mold B, and the shaping operation is completed by the punch 1 of the shaping mold B;

4. Back-extrusion process

The semi-finished product of the tapered leaky nozzle after being shaped by the shaping die B is ejected by the ejector rod 4 of the shaping die B, and moved to the cavity of the die 2 of the reverse extrusion die C, and the back extrusion is completed by the punch 1 of the reverse extrusion die C;

5. Upsetting extrusion molding process

The semi-finished product of the tapered leak nozzle after reverse extrusion by reverse extrusion die C is ejected by ejector pin 4 of reverse extrusion die C, and moved to cavity 2 of concave die of upsetting extrusion die D, and punched by punch 1 of upsetting extrusion die D Upsetting and extruding to complete the pre-punching;

6. Punching process

The semi-finished tapered leak nozzle formed by the upsetting extrusion die D is ejected by the ejector pin 4 and moved to the punching die

In cavity 2 of die E, the punch 1 of punching die E punches forward until the inner hole is punched through, and the inner hole and skin are recovered as a whole, finally meeting the design requirements of the tapered leak.

In the softening treatment process, the annealing and softening treatment temperature is 1050-1150°C, and the treatment time is 0.5-1 hour;

In the shaping process, reverse extrusion process, upsetting extrusion forming process and punching process, the punching pressure is 300-700 Newtons, and the punching speed is 0.05-0.2 m/s.

Production practice shows that the production cycle of the bushing assembled with the tapered nozzle produced by the process of the present invention is significantly lower than that of the bushing assembled with the nozzle made of integral stamping and cutting, the platinum alloy has low processing loss and stable performance, and at the same time The production efficiency of the wire drawing operation is greatly improved, the wire drawing output is high, and the bushing plate has a long service life. The tapered leak nozzle leak plate produced by the invention has been widely used in the glass fiber drawing production of domestic pond kilns and ball kilns, and has produced good economic and social benefits.

Table 1 lists some domestic and foreign processing tank kiln drain plate user assessment performance data comparison (with 1600 hole drain plate as reference).

Table 1 Comparison table of user assessment performance data of some domestic and foreign processing tank kiln drain plate users

Description of drawings

Fig. 1 is a schematic diagram of blank size;

Fig. 2 is the structural representation of mold A;

Fig. 3 is the structural representation of mold B;

Fig. 4 is the structural representation of mold C;

Fig. 5 is the structural representation of mold D;

Fig. 6 is the structural representation of mold E;

Fig. 7 is a schematic diagram of the structure of a tapered leak nozzle.

Detailed ways

Example 1

Take the tapered leak nozzle of the 1600-hole leak plate as an example, the required material is platinum rhodium 10, the outer diameter of the leak nozzle root ΦD=2.8 mm, the outer diameter of the mouth ΦD1=2.4 mm, the inner hole diameter Φd=1.6 mm, the tapered leak nozzle Long L=5.5 millimeters, outer conical surface taper angle α=8 °.

As shown in Fig. 2-Fig. 6, there are 5 sets of moulds, respectively mold A, mold B, mold C, mold D and mold E in the press used in the present invention, wherein mold A, mold B, mold C and mold D Similar in structure, they are all composed of punch 1, die 2, die 3, ejector pin 4 and lower die base 5. Die E is also provided with a discharge chute 6 because it needs to recover excess material with inner holes and skins.

Die A is a pre-shaping mould, the heads of the punch 1 and the ejector pin 4 are thin columns, and the tops have conical protrusions, which are used to form a central cavity at both ends of the blank, so as to find the center in the subsequent process. Die 2 is contained in the lower die holder 5, fixed by die 3. Die 2 cavity is a straight hole with a diameter of φ2.55 mm and a length of 6 mm.

Die B is a plastic mould. In die B, the front part of the die 2 cavity is a straight hole with a length of 4.5 mm and an aperture of φ2.7 mm (the aperture is larger than the die A die 2 aperture), and the rear length is 1.5 mm, which is a cone. Hole, taper hole taper is 9.5°.

Die C is a reverse extrusion die. In die C, the head of punch 1 has a columnar protrusion, and a thin-walled circular hole is pre-extruded at the end of the billet. The front portion of the mold 2 cavity is a straight hole with a length of 4 millimeters and an aperture of φ2.79 millimeters (the aperture is greater than the aperture of the mold B die 2), and the rear length is 2 millimeters, which is a tapered hole with a taper of 9.5°.

Die D is an upsetting extrusion molding die, punch 1 is used for pre-punching, and has a thin and long structure, and the shape of the cavity of die 2 is the external shape of the leaking mouth product.

Die E is a punching die, and punching is mainly completed by punch 1 and die 2. The outer diameter of the working head of punch 1 is the same as the inner diameter of the leaky semi-finished product processed by die D. The die 2 is screwed and fixed on the lower die base 5 through the die 3. The cavity of the die 2 is a tapered hole with a taper of 8°. , 2 mm long. The lower mold base 5 is provided with a discharge chute 6 . The inner opening of the discharge chute 6 is connected with the die 2 .

The processing technology of platinum alloy conical leak nozzle includes softening treatment process, cutting process, shaping process, reverse extrusion process, upsetting extrusion forming process and punching process. The process steps and process conditions are as follows:

1. Softening process

The initial diameter of the billet ΦD1 is equal to the outer diameter of the mouth of the leaking nozzle, which is Φ2.4 mm. Platinum-rhodium 10 raw materials were prepared into thin filament blanks with an initial diameter of ΦD1 = 2.4 mm and a length of 5000 mm, and were annealed and softened at 1100° C. for 40 minutes. Then insert one end of the blank into the wheel-type feeding device to prepare for the feeding of the blank into the cutting process;

2. Cutting process

According to the principle of constant volume of the leak nozzle, the initial length L1 of the leak nozzle blank is calculated to be 4.6 mm. Feed the silk blank in the previous process through the wheel pressure feeding device, and cut it off with a cutter when the length of L1=4.6 mm is fed;

3. Shaping process

The shaping process is mainly to eliminate the defects of the end face of the billet after cutting, to make the quality of the billet evenly distributed, and to reduce the eccentric load of the extrusion punch, which is a necessary process to ensure product quality.

This process includes two processes: pre-shaping by mold A, and shaping by mold B to complete. The blank obtained from the previous cutting process is first pinched and moved to the cavity of the die 2 of the die A through the caliper-type feeding device, and pre-shaped by the punch 1 of the die A of the die A, as shown in Figure 2. After being ejected by the ejector pin 4 of the mold A, it is pinched and moved to the cavity of the die 2 of the die B by the caliper feeding device, and the shaping is completed by the punch 1 of the die B, as shown in Figure 3. For the two forward punches in this process, the pressure is 500 Newtons, and the forward punch speed is 0.1 m/s;

4. Back-extrusion process

The reverse extrusion process is to extrude two conical dimples on the two end faces of the semi-finished conical leak nozzle obtained through shaping, which play a positioning role for the pre-extrusion of the round hole and thin wall. The round hole of the conical socket should not be too deep to ensure that the outer contour of the conical leak is full; it should not be too shallow to ensure the processing length of the thin-walled tube. Through calculation and experiment, it is known that the hole depth is 0.5-0.7mm.

This process is completed by mold C. The semi-finished product of the tapered leaky mouth shaped by the mold B is ejected by the ejector pin 4 of the mold B, and is pinched and moved to the cavity of the concave mold 2 of the mold C through the caliper-type feeding device, and the punch 1 of the mold C is punched back. Squeeze, the punching pressure is 500 Newtons, and the punching speed is 0.1 m/s, as shown in Figure 4;

5. Upsetting extrusion molding process

The upsetting extrusion molding process is to extrude the thin-walled tube with a tapered leak nozzle at one time. Complete the processing of the root outer diameter φD=2.8mm, the mouth outer diameter ΦD1=2.4mm, the cone angle α=8°, the length dimension L=5.5mm and the pre-punching hole with the inner diameter φd=1.6mm. This process is completed by die D.

The semi-finished tapered leak nozzle after being back-extruded by die C is ejected by the ejector rod 4 of die C, and is pinched and moved to the cavity of die 2 of die D through the caliper feeding device, and is punched by the punch 1 of die D For upsetting extrusion molding, the punching pressure is 500 Newtons, and the punching speed is 0.1 m/s, as shown in Figure 5.

6. Punching process

The punching process is mainly to complete the deep punching after the die D upsetting and extruding the pre-punching hole and punch out the inner hole and the skin. This process is completed by die E. The semi-finished tapered leak nozzle formed by upsetting and extrusion of die D is ejected by the ejector rod 4 of die D, and is moved to the cavity of die E by pinching through the caliper type feeding device, and is completed by the punching die 1 of die E For punching, the punching pressure is 500 N, the punching speed is 0.1 m/s, and the inner hole is completely punched through. The flushed inner hole and skin are dropped into the container through the discharge chute 6 for collection. Take out when mold 1 returns, collect by container, as shown in Figure 6.

Claims (3)

1. The processing technology of platinum alloy conical leak nozzle is characterized in that it includes softening treatment process, cutting process, shaping process, reverse extrusion process, upsetting extrusion forming process and punching process, and its process steps and process conditions are as follows: 1. Softening process The initial diameter of the billet ΦD1 is equal to the outer diameter of the mouth of the tapered leak nozzle, and the platinum alloy raw material is prepared into a thin filament billet with an initial diameter of ΦD1, which is annealed and softened; 2. Cutting process According to the principle of constant volume of the tapered leak nozzle, the initial length L1 of the leak nozzle blank is calculated, and the wire blank in the previous process is fed through the feeding device, and when the length of L1 is fed, it is cut off with a knife; 3. Shaping process The blank obtained by the cutting process is moved to the cavity of the die (2) of the pre-shaping die A on the press, and the pre-shaping is carried out by the punch (1) of the pre-shaping die A; After shaping, the semi-finished tapered leak nozzle is ejected by the ejector pin (4) of the pre-shaping mold A, and then moved to the cavity of the concave mold (2) of the shaping mold B, and is punched forward by the punch (1) of the shaping mold B Complete plastic work; 4. Back-extrusion process The semi-finished product of the tapered leaky nozzle after being shaped by the shaping die B is ejected by the ejector pin (4) of the shaping die B, and moved to the cavity of the concave die (2) of the reverse extrusion die C, and the convex die (1) of the reverse extrusion die C Forward punching completes back extrusion; 5. Upsetting extrusion molding process The semi-finished product of the tapered leak nozzle after being back-extruded by the reverse extrusion die C is ejected by the ejector pin (4) of the reverse extrusion die C, and moved to the cavity of the die (2) of the upsetting extrusion die D, and then the punch of the upsetting extrusion die D (1) The front punch completes the upsetting and extrusion forming, and completes the pre-punching; 6. Punching process The semi-finished tapered leak nozzle formed by the upsetting extrusion die D is ejected by the ejector pin (4) of the upsetting extrusion die D, and moved to the cavity of the die (2) of the punching die E, and the punch of the punching die E (1) Forward punching and punching until the inner hole is punched through, and the inner hole and skin are recovered as a whole, and finally meet the design requirements of the tapered leak nozzle. 2. The processing technology of platinum alloy tapered leak nozzle according to claim 1, characterized in that: in the annealing and softening treatment process, the annealing and softening temperature is 1050-1150° C., and the treatment time is 0.5-1 hour. 3. The processing technology of platinum alloy tapered leak nozzle according to claim 1 or 2, characterized in that: in the shaping process, reverse extrusion process, upsetting extrusion forming process and punching process, the pre-punching pressure is 300-700 Newton, The forward speed is 0.05-0.2 m/s.

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