CN102078920A - Method for processing hard alloy rock drill bit - Google Patents

Abstract

The invention discloses a method for processing a hard alloy rock drill bit. The method comprises the following steps of: manufacturing a drill bit wax die; embedding a hard alloy blade and a cooling seat assembly into the wax die; soaking the wax die into a coating, and manufacturing a wax die coating shell layer after drying; after the manufacture of the shell is completed, dissolving out the wax die in hot water of between 92 and 98 DEG C to form a die shell; after the de-waxed die shell is baked for 0.5 hour at the temperature of between 850 and 950 DEG C, pouring the molten steel into the die shell; and cleaning the surface die shell after cooling to obtain an integral fine casting of the drill bit. The method has the advantages of simple production process and low cost; and the hard alloy blade and the drill bit matrix are melted together so as to greatly improve the connecting strength.

Description

The processing method of carbide alloy rock drill bit

Technical field

The present invention relates to a kind of processing method of carbide alloy rock drill bit.

Background technology

Rock drill bit is the perishable tool that stress condition is the harshest, service life is the shortest, technology content is very high in human all iron and steel facility.The process route that existing bore bit production is adopted is: scale blanking → lugs reaming, flat head chamfering → Frequency Induction Heating → die forging → planar end surface → and towards taper hole, the measured length → centering → turning → car heel teeth conical surface → wash alloy film trap → brill water hole → deburring, cleaning, the cooperation gold plaque → soldering → bore bit sandblast → 110 ℃ of sword face → cylindrical grinding conical surface → marks of mill → spray paint → pack, put in storage.Because existing process using carbide chip uses soldering on the steel body, so the bonding strength at carbide chip and matrix is not high, very easily cause carbide chip become flexible, take off brave, cataclasm, fall problems such as sheet, and the cost height, consume big, wear no resistance, had a strong impact on its operating efficiency and service life.

Summary of the invention

In order to solve the above-mentioned technical problem that existing bore bit production exists, the invention provides the processing method of the carbide alloy rock drill bit that a kind of technology is simple, cost is low, wearability is good.

The technical scheme that the present invention solves the problems of the technologies described above is:

With metal die the finish cast die material is pressed into mould with high pressure, makes and the consistent wax-pattern of bore bit shape, wax-pattern is provided with the groove of carbide inserts blade;

Carbide chip is contained on the refrigerating seat, the refrigerating seat assembly is bumped in the groove of wax-pattern;

The system shell, system shell step is as follows:

Ground floor is a surface layer, and coating preparation adds 3.6 part of 325 purpose zirconium English powder by 1 part of Ludox, and accounts for coating and weigh 0.1% wetting agent and account for coating and weigh 0.1% defoamer, and forms through fully stirring; Wax-pattern is immersed in the coating, after the trickling evenly, spread 80-120 order zircon sand, dry again;

Second ~ layer 6 is a back-up coat, and coating is formulated as 1 part of Ludox and adds 1 part of 200 order mullite powder and 0.25 part of graphite powder, after fully stirring, the shell group of having made ground floor is immersed wherein, and stucco then, drying is 8 ~ 12 hours behind every layer of system shell;

After finishing the system shell, in 92 ℃ ~ 98 ℃ hot water,, form shell with the wax-pattern stripping;

Shell after the dewaxing, pours into the molten steel that melts wherein after 0.5 hour 850 ℃ ~ 950 ℃ bakings;

After cooling, surperficial shell is cleaned out, promptly get the whole precision castings of bore bit.

In the processing method of above-mentioned carbide alloy rock drill bit, the sand that is added in the described system shell step is the mixture of 0.7 part of 16-30 order mullite sand and 0.3 part of 16-30 order graphite sand.

Technique effect of the present invention is: the present invention utilizes the wax mould case, and medium graphite that the adding thermal conductivity is good in housing and the zirconium English material that thermal conductivity is good, heat storage capacity is big, can cool off molten steel fast, prevent that the high temperature of molten steel from destroying the performance of carbide chip, improve long service life, in addition, adopt carbide chip and bore bit matrix to fuse into one, improved bonding strength greatly.Production technology of the present invention is simple, also greatly reduces production cost.

The present invention is further illustrated below in conjunction with specific embodiment.

Description of drawings

Fig. 1 is the refrigerating seat installation diagram of carbide chip among the present invention.

Fig. 2 is wax-pattern and refrigerating seat installation diagram among the present invention.

The specific embodiment

Fig. 1, Fig. 2 explanation: 1 is carbide chip, and 2 is refrigerating seat, and 3 are the assembly for carbide chip and refrigerating seat, and 4 is wax-pattern.

Machining process of the present invention describes in detail:

1: at first use metal die, (temperature adjusting is 50 ℃ ~ 52 ℃ resin, a paraffinic base mixing mould material, in the pasty state) is pressed into mould with high pressure, forms wax-pattern with the finish cast die material.Wax-pattern is consistent with the bore bit part shape, but reserves the groove of carbide inserts blade.

2: carbide chip is contained on the refrigerating seat.Refrigerating seat is accurate steel-casting, and the dovetail groove bottom carbide alloy assembles both, as shown in Figure 1.

3: the above-mentioned carbide chip that assembles and refrigerating seat assembly are bumped in the groove of wax-pattern (as Fig. 2).

4: enter system shell process subsequently, carry out six layers of system shell altogether.

Ground floor is a surface layer, and coating preparation adds 3.6 parts of zirconium English powder (325 order) by 1 part of Ludox and 0.1%(coating is heavy) special-purpose wetting agent and 0.1%(coating is heavy) dedicated defoamer, and form through fully stirring.Wax-pattern is immersed in the coating, after the trickling evenly, spread 80/120 order zircon sand, then dry 8 hours.

Second ~ layer 6 is a back-up coat, and coating is formulated as 1 fen Ludox and adds 1 fen mullite powder (200 order), for accelerating cooling, adds 0.25 part of graphite powder in addition in this coating, after fully stirring, the shell group of having made ground floor is immersed wherein stucco then.For strengthening cooling effect, adopt complex sand, complex sand has 0.7 part of 16/30 order mullite sand, 0.3 part of 16/30 order graphite sand, drying is 8 ~ 12 hours behind every layer of system shell.

5: after finishing the system shell, dewax after dry 12 hours: with the wax-pattern stripping, form ghost in 92 ℃ ~ 98 ℃ hot water, its cavity shape is consistent with the bore bit part.

6: the shell after the dewaxing, pours into the molten steel that melts wherein after 0.5 hour through baking (850 ℃ ~ 950 ℃).

7: after cooling, surperficial shell is cleaned out, promptly got the whole precision castings of bore bit.

8: according to various different requirements, whole bore bit can be heat-treated, to improve the mechanical performance of bore bit integral body.

9: whole bore bit is carried out shotblasting handle, and ornamental processing.

General condensed summary:

1: show that according to research and experimental result employed carbide chip does not have influence in the temperature below 1400 ℃ to performance.

2: 1400 ℃ ~ 1600 following time of staying of high temperature no longer than 120 seconds, the carbide alloy performance indications are not had influence.

3: owing to increased refrigerating seat, and in coating, use the good medium graphite of thermal conductivity, surface layer has adopted thermal conductivity better simultaneously, the zirconium English material that heat storage capacity is big, so though the pour steel temperature is up to 1550 ℃, but can be cooled to below 1400 ℃ in back 1 minute in cast, so guaranteed that the carbide alloy performance is unaffected.

Claims (2)

1. the processing method of a carbide alloy rock drill bit may further comprise the steps:

With metal die the finish cast die material is pressed into mould with high pressure, makes and the consistent wax-pattern of bore bit shape, wax-pattern is provided with the groove of carbide inserts blade;

Carbide chip is contained on the refrigerating seat, the refrigerating seat assembly is bumped in the groove of wax-pattern;

The system shell, system shell step is as follows:

Ground floor is a surface layer, and coating preparation adds 3.6 part of 325 purpose zirconium English powder by 1 part of Ludox, and accounts for coating and weigh 0.1% wetting agent and account for coating and weigh 0.1% defoamer, and forms through fully stirring; Wax-pattern is immersed in the coating, after the trickling evenly, spread 80-120 order zircon sand, dry again;

Second ~ layer 6 is a back-up coat, and coating is formulated as 1 part of Ludox and adds 1 part of 200 order mullite powder and 0.25 part of graphite powder, after fully stirring, the shell group of having made ground floor is immersed wherein, and stucco then, drying is 8 ~ 12 hours behind every layer of system shell;

After finishing the system shell, in 92 ℃ ~ 98 ℃ hot water,, form shell with the wax-pattern stripping;

Shell after the dewaxing, pours into the molten steel that melts wherein after 0.5 hour 850 ℃ ~ 950 ℃ bakings;

After cooling, surperficial shell is cleaned out, promptly get the whole precision castings of bore bit.

2. the processing method of carbide alloy rock drill bit according to claim 1, the sand that is added in the described system shell step is the mixture of 0.7 part of 16-30 order mullite sand and 0.3 part of 16-30 order graphite sand.

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