CN206845103U - Polycrystalline diamond compact bit - Google Patents

Abstract

A kind of polycrystalline diamond compact bit, comprising：PDC pieces, and diamond thin, formed in the PDC pieces upper surface, it is characterised in that also include：One silicon nitride layer or silicon carbide layer, formed between the PDC pieces and diamond thin；Planarization layer, formed between the diamond thin and the silicon nitride layer or silicon carbide layer.To sum up, drill bit structure provided by the utility model improves the homogeneity of diamond film layer.

Description

Polycrystalline diamond compact bit

Technical field

A kind of polycrystalline diamond compact bit is the utility model is related to, belongs to machinery and field of tool.

Background technology

Composite polycrystal-diamond (polycrystallinediamondcompact, PDC) belongs to new function material, It is to sinter to form under the conditions of high pressure high temperature with cemented carbide substrate using diadust, both the height with diamond was hard Degree, high-wearing feature and thermal conductivity, there is the intensity and toughness of hard alloy again, be manufacture cutting tool, drilling bit And the ideal material of other wear resistant tools.

Composite sheet is at home and abroad competitively developed and produced, and description is many because of the superiority of itself.U.S. GE Company is the manufacturer for releasing composite sheet at first, and its major product has compax, rear to produce stratapax, the latter again To drill special product, its wearability l00~150 times higher than hard alloy, can be matched in excellence or beauty with natural diamond.Other are such as south It is non-, Japanese also all to release different types of composite sheet 70~eighties of 20th century.China grinds since early 1980s Diamond compact processed, 1975, Chengdu instrument developed FJ series of cutting tools PDC, and 1979, Beijing artificial lens was ground Make JYF type PDC blades, 1981, the grinding wheel factory of Kweiyang the 6th developed JFS-F Series P DC blades, 1987, Zhengzhou abrasive material Grinding tool grinding research institute successfully develops oil bit PDC, and 1988 carry out small lot production, commercial disignation JFZR, nineteen ninety Set up new Asia company to accomplish scale production, greatly accelerate popularization and applications of the PDC in China.So far, domestic PDC specifications are neat Entirely, the needs of the national economic development are disclosure satisfy that substantially.

Cobalt is the catalyst of graphite and the mutual phase in version of diamond.It can make graphite be converted into diamond under high pressure-temperature, But it is not high enough in normal pressure or pressure and in the case that temperature is higher, promote diamond to be converted into graphite again.Due to polycrystalline diamond Contain a small amount of cobalt in layer, therefore its temperature tolerance is poor, can only be resistant to 700 DEG C of temperature.When temperature is higher than 700 DEG C or though temperature is low In but for a long time close to 700 DEG C when, corrosion function of the one side cobalt to diamond causes diamond particles grain boundaries graphitization, knot Close intensity to be deteriorated, on the other hand the cobalt of residual is more much higher than the thermal coefficient of expansion of diamond, and its high-temperature expansion drives diamond Intergranular associative key is broken so that PDC layer becomes loose or even cracked.Temperature is higher, and this influence is bigger.

Drill bit used is much as brill tooth using this PDC pieces in oil exploitation.Diamond is that the current mankind can obtain The most hard material obtained, this characteristic allow diamond compact bit to obtain very long service life.Fabulous drill bit can Disposably to complete the probing of a bite oil well, without repeatedly more bit change.

As people are to improving well-digging efficiency and reducing the continuous improvement of drilling cost requirement, traditional PDC drill bit tooth is got over To get over the needs that can not meet well-digging at a high speed.Because well-digging speed improves, then the PDC parts of drill bit are cut with rock silt grinds The speed cut will improve, and then the temperature on PDC surfaces will improve, and case hardness and intensity decline, and are bored so as to seriously reduce The service life of head.

People employ many methods to improve the resistance to elevated temperatures of PDC teeth.The method that most enterprises use is to improve PDC Layer in diamond particles bond strength, reduce PCD layer in remaining cobalt content.

UK corporation ReedHycalogUK, Ltd. obtain the patent that cobalt is removed in an acid treatment UnitedStatesPatentNo.6,861,098.The content of patent is to make PDC layer table using acid corrosion or other chemical methodes The cobalt of face and certain depth is removed, and the position of its original becomes small cavity one by one.Although this method is so that PCD layer table The intensity in face declines 20-30%, but because top layer certain depth no longer contains cobalt, its temperature tolerance is greatly improved, and drill bit makes Also it is greatly improved with the life-span.

Though the way of the patent largely improves the performance of PDC drill bit tooth, because PCD top layers are present a lot Micropore, its impact resistance have dropped more than 20%.In addition, the presence of micropore also prevents PDC drill bit tooth from reaching optimal resistance to Mill property and service life.

In addition, even if PDC pieces surface formed with diamond thin, but diamond thin is often peeling-off comes off, can not Reach the intensity in work and high adhesion force requirement.

Utility model content

In order to overcome the shortcomings of prior art construction, the utility model provides a kind of polycrystalline diamond compact bit.

Polycrystalline diamond compact bit, comprising：PDC pieces, and diamond thin, formed in the PDC pieces upper surface, its feature It is, also includes：One silicon nitride layer or silicon carbide layer, formed between the PDC pieces and diamond thin；Planarization layer, shape Into between the diamond thin and the silicon nitride layer or silicon carbide layer.

Alternatively, the thickness of the PDC pieces is 2-10mm.

Alternatively, the thickness of the diamond thin is 0.5-1mm.

Alternatively, the thickness of the silicon nitride layer or silicon carbide layer is 0.01-0.1mm.

Alternatively, the thickness of the silicon nitride layer or silicon carbide layer is 0.05-0.08mm.

Alternatively, the planarization layer is polyvinyl alcohol laurate.

To sum up, drill bit provided by the utility model improves the homogeneity of diamond film layer.

Brief description of the drawings

Fig. 1 is the section graph structure of the utility model drill bit.

Embodiment

Further illustrate the technical solution of the utility model below in conjunction with the accompanying drawings and by embodiment.It can manage Solution, specific embodiment described herein are used only for explaining the utility model, rather than to restriction of the present utility model.Separately It is outer it should also be noted that, illustrate only the part related to the utility model for the ease of description, in accompanying drawing and not all interior Hold.

Identical number represents same or analogous component in schema.On the other hand, well-known component and step be simultaneously It is not described in embodiment, to avoid causing the utility model unnecessary limitation.

Prepare embodiment 1

As shown in figure 1, a kind of polycrystalline diamond compact bit, using chemical vapor deposition method PDC pieces 101 PDC tables Face is sequentially depositing one layer of silicon nitride 1021 and the cvd diamond film 103 of one layer of 0.5-1mm thickness.Due to setting for silicon nitride 1021 Put, the stress between PDC pieces 101 and diamond thin 103 can be slowed down, so as to reduce diamond thin from PDC pieces 101 The risk to come off.Wherein, the thickness of silicon nitride 1021 is 0.01-0.1mm, preferably 0.05-0.08mm, in addition, silicon nitride material It can also be replaced with carbofrax material.Further, inventor has done substantial amounts of experimental study, have found diamond thin 103 Coating layer thickness preferred scope, when the thickness of diamond thin 103 is 0.5-1mm, whole thin diamond film strength and work Adhesive force when making has reached most preferably, and when thickness is less than 0.5mm, the intensity of Buddha's warrior attendant film layer can not reach requirement, work as Buddha's warrior attendant When the thickness of stone film is more than 1mm, adhesive force when Buddha's warrior attendant film layer works is it is possible that some problems.In addition, PDC pieces Thickness is 2-10mm.In addition, also including a planarization layer 1022 between diamond thin and silicon nitride layer or silicon carbide layer, this is flat The making of smooth layer is in order to which before depositing diamond, one layer of flat film of formation is flat to strengthen the homogeneity of diamond The material for changing layer can be polyvinyl alcohol laurate.

The utility model can also have other various embodiments, in the situation without departing substantially from the utility model spirit and its essence Under, those skilled in the art work as can make various corresponding changes and deformation according to the utility model, but these are corresponding Change and deformation should all belong to scope of the claims appended by the utility model.

Preferred embodiment of the present utility model is these are only, it is all in the utility model not to limit the utility model Spirit and principle within, any modification, equivalent substitution and improvements made etc., should be included in protection model of the present utility model Within enclosing.

Claims (6)

1. a kind of polycrystalline diamond compact bit, comprising：

PDC pieces, and

Diamond thin, formed in the PDC pieces upper surface, it is characterised in that also include：

One silicon nitride layer or silicon carbide layer, formed between the PDC pieces and diamond thin,

Planarization layer, formed between the diamond thin and the silicon nitride layer or silicon carbide layer.

2. polycrystalline diamond compact bit as claimed in claim 1, it is characterised in that：The thickness of the PDC pieces is 2-10mm.

3. polycrystalline diamond compact bit as claimed in claim 1, it is characterised in that：The thickness of the diamond thin is 0.5- 1mm。

4. polycrystalline diamond compact bit as claimed in claim 1, it is characterised in that：The thickness of the silicon nitride layer or silicon carbide layer For 0.01-0.1mm.

5. polycrystalline diamond compact bit as claimed in claim 4, it is characterised in that：The thickness of the silicon nitride layer or silicon carbide layer For 0.05-0.08mm.

6. polycrystalline diamond compact bit as claimed in claim 1, it is characterised in that：The planarization layer is polyvinyl alcohol laurate Ester.