CN110919012A

CN110919012A - Sintering tool clamp for hard alloy thin-wall part spray pipe product

Info

Publication number: CN110919012A
Application number: CN201911300590.9A
Authority: CN
Inventors: 程东军; 李先容; 刘金霞; 齐灵军; 王彤; 马骏
Original assignee: Institute of Materials of CAEP
Current assignee: Institute of Materials of CAEP
Priority date: 2019-12-17
Filing date: 2019-12-17
Publication date: 2020-03-27
Anticipated expiration: 2039-12-17
Also published as: CN110919012B

Abstract

The invention discloses a sintering tool clamp for a hard alloy thin-wall spray pipe product, which comprises at least two clasps, wherein the spray pipe is of a structure with two large ends and a small middle part, the clasps embrace the periphery of the spray pipe during clamping, the neck part on the upper part of the middle part of the spray pipe embraces the spray pipe tightly, the spray pipe and the clamp are integrally inserted into corresponding suspension holes, and finally, a finished spray pipe product is obtained through sintering; the invention reduces the inner diameter of the suspension hole through the clasping clamp, thereby ensuring that the spray pipe can still be stably suspended on the suspension hole even if the spray pipe shrinks in the sintering process, further reducing the rejection rate of products, simultaneously avoiding secondary sintering, improving the production efficiency and reducing the energy consumption and the production cost.

Description

Sintering tool clamp for hard alloy thin-wall part spray pipe product

Technical Field

The invention relates to the technical field of powder metallurgy sintering molding, in particular to a sintering tool clamp for a hard alloy thin-wall part spray pipe product.

Background

In the prior art, hard alloy thin-wall part spray pipe series products are generally manufactured by adopting a powder metallurgy sintering technology, and in the whole production process flow control process, sintering is the last main process which plays a decisive role in the performance of the hard alloy thin-wall part spray pipe series products, so the cost of the sintering process is an important part of the product cost; during sintering, a spray pipe blank is hoisted and sintered through a special mesh hanging rack (shown in figure 1), and because a powder metallurgy product has a certain sintering shrinkage coefficient, the spray pipe can fall off from the hanging rack due to integral shrinkage and gravity action during high-temperature sintering to cause product damage (shown in figure 2), so that in order to reduce the rejection rate, a secondary sintering method is generally adopted in the prior art, firstly, the sintering temperature is reduced when the spray pipe is sintered to a certain degree to enable the product to be partially shrunk, and after the spray pipe is discharged from a furnace, the mesh hanging plate with a corresponding size is replaced to perform secondary sintering; although the rejection rate can be reduced, the method has the disadvantages of long sintering period, and simultaneously, the falling phenomenon of the product is not fundamentally and thoroughly changed because the cooling time is not easy to grasp, and the rejection rate is still high.

Disclosure of Invention

Aiming at the defects of long production period and high energy consumption and rejection rate in the prior art, the invention discloses a sintering tool clamp for a hard alloy thin-wall part spray pipe product, which can be contracted along with the contraction of a blank, and ensures that the blank is always in a stable clamping state, so that the stability of a rough blank is greatly improved, and the blank is prevented from falling and being damaged; meanwhile, after the clamp is adopted, the blank is sintered and formed at one time, so that the production efficiency is improved, and meanwhile, the production cost is greatly reduced.

The invention realizes the aim through the following technical scheme:

a sintering tool clamp for hard alloy thin-wall spray pipe products is characterized in that a spray pipe is hung and sintered by a hanging frame consisting of an original bottom plate, equal-height columns and a mesh plate, and the cross section of the spray pipe is in a form that the upper end and the lower end of the spray pipe are wide and the middle neck of the spray pipe is narrow; the sintering tool fixture is characterized by comprising at least two clasps, wherein during clamping, the clasps embrace the periphery of the spray pipe and clamp the upper part of the neck of the spray pipe, then the clasps are integrally inserted into the mesh plate to realize the limiting suspension of a rough blank of the spray pipe, and finally, a finished product of the spray pipe is obtained through sintering.

Preferably, the cross section of the holding clamp is T-shaped.

Preferably, the upper part of the holding clamp is provided with an arc-shaped thrust surface which is attached to the outer wall of the spray pipe.

Compared with the prior art, the invention has the following beneficial effects:

(1) the invention comprises a plurality of separated clasps, wherein the clasps encircle the periphery of a spray pipe, one end of the outer surface of each clasp is provided with a limiting flange which protrudes outwards along the radial direction, and the other end of the outer surface of each clasp is provided with a limiting surface; when the device is installed, the clasping clamp encircles the periphery of the spray pipe, and after the device is installed, one end of the clasping clamp, which is provided with the limiting surface, is inserted into the corresponding hanging hole, and the limiting surface and the inner wall of the hanging hole are abutted against each other to prevent the clasping clamp from horizontally sliding; the limiting flange and the mesh plate are mutually abutted, so that the suspension stability is ensured; compared with the prior art, the inner diameter of the suspension hole is greatly reduced through the clamp, and the maximum inner diameter of the clamping hole on the clamp is smaller than the maximum outer diameter of the spray pipe after sintering shrinkage, so that the spray pipe can still be stably suspended on the suspension hole even if shrinkage and dropping occur in the sintering process, the rejection rate of products in the sintering process is greatly reduced, and the production cost is reduced.

Meanwhile, the sintered product does not fall off, so that the blank does not need to be sintered for the second time, the production efficiency of the product can be greatly improved, the energy consumption in the production process of the product is reduced, and the production cost is further reduced.

(2) The thrust surface attached to the outer wall of the spray pipe is arranged on the inner side of the clamp, the contact area between the clamp and the blank is increased through the thrust surface, on one hand, unnecessary indentation is prevented from being left on the product, and the product quality is prevented from being affected, on the other hand, the product can be supported in multiple points, so that the stability of the product in the sintering process is improved, the product is prevented from shaking violently in the production process, even colliding with one another, the rejection rate of the product is favorably controlled, and the product quality is improved.

(3) The cross section of the clamp is T-shaped, so that the clamp can be matched with the appearance of the hanging hole, looseness of the clamp in the use process is avoided, meanwhile, the structure can meet the relevant mounting requirements of the clamp, the structure is simple and practical, and the structure of the clamp can be better optimized.

Drawings

FIG. 1 is a schematic view of a prior art thin wall nozzle installed prior to sintering;

FIG. 2 is a schematic representation of a prior art thin wall nozzle after sintering;

FIG. 3 is a schematic structural view of embodiment 1 of the present invention;

FIG. 4 is a schematic structural view of embodiment 2 of the present invention;

FIG. 5 is a schematic view of the pre-sinter mounting of the present invention;

FIG. 6 is a schematic illustration of a post-sinter installation of the present invention;

reference numerals: 1. spray pipe, 2, embrace the card, 3, thrust face, 201, mesh board.

Detailed Description

The present invention will be further described with reference to the following description and examples, which include but are not limited to the following examples.

Embodiment mode 1

The practical mode is taken as a basic embodiment of the invention, and discloses a sintering tool clamp for a hard alloy thin-wall part spray pipe product, which has a specific structure shown in fig. 3, and comprises 2 semicircular holding clamps 2, wherein the inner sides of the holding clamps 2 are clamping grooves for placing a spray pipe 1, and the holding clamps 2 surround the periphery of the spray pipe 1 during installation; the upper end of the outer side surface of the clamp 2 is provided with a limiting flange which extends outwards along the radial direction, the limiting flange is an arc with a central angle of 180 degrees, and the limiting flange and the clamp form a T-shaped structure;

embodiment mode 2

As shown in fig. 4, the present embodiment discloses a sintering tool fixture for a hard alloy thin-walled nozzle product, which includes 3 circular-arc-shaped clasps 2, wherein the inner side of each clasp 2 is a clamping groove for placing the nozzle 1, and the upper end of each clamping groove is provided with a thrust surface 3 having the same shape as the nozzle, and the thrust surface is tapered.

Embodiment 3

The embodiment is a further preferred embodiment of the present invention, and discloses a method for using a cemented carbide thin-walled nozzle product sintering tool fixture, and the embodiment describes in detail a method for using a fixture according to the present invention by taking a cemented carbide thin-walled nozzle product with a height-diameter ratio of more than 4:1 and a diameter difference of upper and lower ends of more than 8mm as an example, and the method comprises the following steps:

s1, assembling a corresponding sintering suspension device through the original bottom plate, the contour columns and the mesh plate 201;

s2, the clasping clamp is attached to the outer surface of the spray pipe blank, the clasping clamp is enabled to be attached to the spray pipe at the position above the neck of the spray pipe blank, the aperture of the mesh plate is slightly larger than the diameter of the small end of the corresponding spray pipe product, therefore, the whole formed by the clamp and the spray pipe is inserted into the hanging hole from the small end, the bottom of the suspended product keeps a certain distance from the original bottom plate, and the top end of the clasping clamp 1 is attached to the mesh plate to achieve positioning and fixing due to the fact that the cross section of the clasping clamp is in a T shape.

And S3, transferring the sintering suspension device with the suspended clasping clamp and the spray pipe into a sintering furnace for sintering.

As shown in fig. 5 and 6, after the locking clip is installed in the hanging hole, all the locking clips are in a static state due to the action of the limiting flange, and the large end of the spray pipe is locked by the clamp due to the special structure of the spray pipe; compared with the prior art, the invention can firstly effectively prevent the spray pipe from falling off in the sintering process fundamentally, thereby greatly reducing the rejection rate of products; on the other hand, the spray pipe does not need to be worried about falling in the whole sintering process, so that the spray pipe sintering operation is not needed to be carried out in a secondary heating mode, the production efficiency of products is greatly improved, the energy consumption in the production process is reduced, and the production cost is further reduced.

The following table is a comparison table of the dimensions of the nozzle tube before and after sintering in embodiment 1

As can be seen from the table, the big head end of the spray pipe after sintering is reduced by 0.3mm compared with the small head end of the spray pipe before sintering, so that the coil pipe can be effectively prevented from falling off in the sintering process by additionally arranging the clamp, and the one-time sintering of the spray pipe is realized.

Claims

1. A sintering tool clamp for hard alloy thin-wall spray pipe products is characterized in that a spray pipe (1) is hung and sintered by a hanging frame consisting of an original bottom plate, an equal-height column and a mesh plate, and the cross section of the spray pipe is in a form that the upper end and the lower end of the spray pipe are wide and the middle neck of the spray pipe is narrow; the sintering tool fixture is characterized by comprising at least two holding clamps (2), wherein during clamping, the holding clamps (2) surround the periphery of the spray pipe (1), clamp the upper part of the neck of the spray pipe (1), and then integrally insert into the mesh plate to realize limiting suspension of a rough part of the spray pipe (1), and finally obtain a finished product of the spray pipe (1) through sintering.

2. The sintering tool clamp for the spray pipe product of the hard alloy thin-walled part according to claim 1, characterized in that: the cross section of the holding clamp (2) is T-shaped.

3. The sintering tool clamp for the spray pipe product of the hard alloy thin-walled part according to claim 1, characterized in that: the upper part of the clamp (2) is provided with an arc-shaped thrust surface (3) which is attached to the outer wall of the spray pipe.