Background technique
In Coal Chemical Industry, coal dust are produced; The valve rod of some valves, particularly valve can receive the friction of high hardness materials such as cinder for a long time; And material usually contains some hard impurity and chemical corrosivity impurity, causes material more serious to the wearing and tearing and the erosion-corrosion of stem surface.Therefore,, Coal Chemical Industry, coal dust need wear-resisting, corrosion resistant valve rod in producing.
At present, adopt the hard-face overlaying welding method to obtain wear-resisting, corrosion-resistant valve rod.Usually valve rod matrix adopting stainless steel is provided combination properties such as the required intensity of opposing external force, toughness, plasticity by matrix, through the hard-face overlaying welding method at substrate surface built-up welding one deck high-abrasive material, to improve surface hardness and to resistance to wear.
Existing hard-face overlaying welding method mainly contains manual electric arc welding, gas shielded arc welding, submerged arc welding etc., and welding rod adopts alloy fusible core welding wire, and cladding layer is prone to uneven thickness and hardness is uneven, causes the adhesion strength of cladding layer and matrix steel part relatively poor.Because when the wearing layer built-up welding is thin, wearing layer is vulnerable to erosion, corrosion spalling during valve rod work, reduces the operating life of valve rod; So wearing layer needs built-up welding thicker; Promptly need the cladding of built-up welding multilayer, by relatively poor because of cladding layer and matrix steel part adhesion strength, fusion intensity is lower; Wearing layer is prone to peel off during the cladding of built-up welding multilayer, also reduces the operating life of valve rod.Therefore, adopt the existing hard-face overlaying welding method can only the cladding of built-up welding individual layer, the wearing layer that promptly adopts existing hard-face overlaying welding method to obtain be one deck cladding.
But; Cladding layer is that one deck causes wearing layer thinner; Valve rod uses in the rugged environment of Coal Chemical Industry, coal deep processing; Wearing layer is prone to erosion, peels off, and finally reduces the working life of valve rod, makes its rugged environment that can not satisfy Coal Chemical Industry, coal deep processing to the valve rod requirement in working life.
In sum, how a kind of valve rod being provided, improving the working life of valve rod, and then making valve rod satisfy the rugged environment of Coal Chemical Industry, coal deep processing to the requirement in its working life, is present those skilled in the art's problem demanding prompt solution.
The model utility content
In view of this, the utility model provides a kind of valve rod, improved the operating life of valve rod, and then makes valve rod satisfy the requirement of the rugged environment of Coal Chemical Industry, coal deep processing to its working life.
In order to achieve the above object, the utility model provides following technological scheme:
A kind of valve rod comprises valve rod matrix and the wearing layer that is wrapped in the working end outer surface of said valve rod matrix, and said wearing layer comprises cemented carbide laser cladding layer, Tungsten carbite vacuum sintering layer and the nano coating that distributes successively from said valve rod matrix surface.
Preferably, in the above-mentioned valve rod, the outer surface of said working end is the gradient face.
Preferably, in the above-mentioned valve rod, the valve rod matrix is the steel matrix.
Based on the above-mentioned valve rod that provides, the utility model also provides a kind of valve, comprises valve rod and spool, and said valve rod is above-mentioned any described valve rod.
In the valve rod that the utility model provides, the wearing layer that is wrapped in valve rod matrix working end is three layers, compared with prior art, has improved the wear-resisting property of wearing layer significantly; The first layer wearing layer is the cemented carbide laser cladding layer simultaneously; Mainly act as and improved cladding layer and valve rod high base strength; Second layer wearing layer is a Tungsten carbite vacuum sintering layer; Improved the hardness and the uniformity of wearing layer, the 3rd layer of wearing layer is nano coating, further improves hardness, toughness and the Corrosion Protection of wearing layer.Therefore, the valve rod that the utility model provides has improved the operating life of valve rod, and then makes valve rod satisfy the requirement of the rugged environment of Coal Chemical Industry, coal deep processing to its working life.
Embodiment
The utility model provides a kind of valve rod, has improved the operating life of valve rod, and then makes that met the demands its working life when valve rod was worked in the rugged environment of Coal Chemical Industry, coal deep processing.
To combine the accompanying drawing among the utility model embodiment below, the technological scheme among the utility model embodiment is carried out clear, intactly description, obviously, described embodiment only is the utility model part embodiment, rather than whole embodiments.Based on the embodiment in the utility model, those of ordinary skills are not making the every other embodiment who is obtained under the creative work prerequisite, all belong to the scope of the utility model protection.
Please refer to accompanying drawing 1-2, the structural representation of the valve rod that Fig. 1 provides for the utility model embodiment; The structural representation of the wearing layer on the valve rod that Fig. 2 provides for the utility model embodiment.
The valve rod that the utility model embodiment provides; Comprise valve rod matrix 2 and the wearing layer 1 that is wrapped in working end 21 outer surfaces of said valve rod matrix 2, wearing layer 1 comprises cemented carbide laser cladding layer 11, Tungsten carbite vacuum sintering layer 12 and the nano coating 13 that distributes successively from valve rod matrix 2 surfaces.
In the valve rod that the utility model provides, the wearing layer 1 that is wrapped in working end 21 is three layers, compared with prior art, has improved the wear-resisting property of wearing layer 1 significantly; First layer wearing layer 11 is the cemented carbide laser cladding layer simultaneously; Mainly act as the adhesive strength that has improved cladding layer and valve rod matrix 2; Second layer wearing layer 12 is a Tungsten carbite vacuum sintering layer; Improved the hardness and the uniformity of wearing layer 1, the 3rd layer of wearing layer 13 is nano coating, further improves hardness, toughness and the Corrosion Protection of wearing layer 1.Therefore, the valve rod that the utility model provides has improved the operating life of valve rod, and then makes valve rod satisfy the requirement of the rugged environment of Coal Chemical Industry, coal deep processing to its working life.
In the above-mentioned valve rod; First layer wearing layer 11 adopts laser melting coatings, and laser melting coating has that dilution is little, dense structure, adhesive strength are high, the uniform characteristics of cladding layer; Thickness 1.5~the 2mm of first layer wearing layer 11, its surface hardness can reach HRC42 (Rockwell hardness number is 42).
HR represents Rockwell hardness, and it is standard that a kind of method for expressing of hardness, C are represented accepted scale C, and HRC is the hardness that adopts 150Kg load and diamond awl injector to try to achieve, and is used for the very high material of hardness.
Preferably, the carbide alloy welding wire of above-mentioned first layer wearing layer 11 employings is the Stellite hardfacing alloy.Stellite hardfacing alloy: be meant to contain chromium 25-33% tungstenic 3-21%, the cemented carbide of carbon containing 0.7-3.0%.Because Stellite melting welding cladding good penetrability, can well improve stiff dough and valve rod matrix infiltration adhesive strength, with valve rod matrix permeability layer about 2mm, Stellite laser melting coating layer thickness 1.5-2mm, realization stiff dough hardness HRC42.
In the above-mentioned valve rod; Second layer wearing layer 12 adopts the Tungsten carbite vacuum sintering technique; The alloy blending material that in Tungsten carbite, adds a certain proportion of molybdenum carbide, titanium carbide, tantalum carbide formation is coated on the first layer wearing layer 11; When being heated to uniform temperature, the melt-phase fusion in the alloy is also soaked into the surface of solid-state valve rod matrix, and the diffusion that has begun between coating and the valve rod matrix 2 is dissolved each other and interface reaction; Wait to spread to dissolve each other will form the district of dissolving each other of containing both sides' composition at the inner boundary of coating and valve rod matrix 2 after to a certain degree, during condensation coating distinguish with dissolving each other recrystallization and with the valve rod matrix securely metallurgical junction synthesize an integral body.Thereby reach second layer wearing layer 12 even tissue; Improve the high temperature hardness and the adhesion strength of wearing layer 1; It is poor with the contraction of wearing layer 1 material to reduce valve rod matrix 2 through high-temp alloying simultaneously, prevents to shrink because of unlike material defectives such as the contraction layering that causes, weld cracking.
Simultaneously,, improve wettability and wrap angle, suppress grain growth, to realize better stiff dough Organizational Structure to Tungsten carbite through Tungsten carbite being added the improvement of tantalum carbide, molybdenum carbide, titanium carbide material.
What the Tungsten carbite vacuum sintering was realized is two kinds of metallurgy combination that material is firm, and adhesive strength is high, and the thickness of clinkering layer is 1-6mm, realizes stiff dough hardness HRC60-62.
In the existing technology; The hardness on valve rod wearing layer surface can only reach HRC42-52; In the valve rod that the utility model embodiment provides obviously, the surface hardness of wearing layer 1 is significantly greater than the surface hardness of wearing layer of the prior art, and promptly the wearing layer 1 that provides of the utility model embodiment has improved its surperficial hardness number; Improved the wear-resisting property of wearing layer 1, and then the working life of having improved valve rod.
In the above-mentioned valve rod; The 3rd layer of wearing layer 13 is to adopt nano coatings such as chromium nitride, titanium nitride, titanium carbonitride to be applied to the surface of second layer wearing layer 12; Improve hardness, adhesion, toughness and the Corrosion Protection of wearing layer 1; The 3rd layer of wearing layer 13 has only 0.002~0.006mm, and the hardness of the 3rd layer of wearing layer 13 can reach HV2000~3000 (Vickers hardness 2000~3000), is HRC207~311.
HV represents Vickers hardness, a kind of expression mode of hardness.The hardness number that HV289 representes is identical with the hardness number that HRC30 representes.
Preferably, in the valve rod that the foregoing description provides, the outer surface of working end 21 is the gradient face.Above-mentioned wearing layer 1 also can be arranged on the gradient face, and the utility model is not done concrete qualification to the shape of the working end 21 of valve rod matrix 2.
Concrete, in the valve rod that the foregoing description provides, valve rod matrix 2 is the steel matrix.
The utility model embodiment also provides a kind of valve, comprises valve rod and spool, and valve rod is the valve rod described in the foregoing description.
To the above-mentioned explanation of the disclosed embodiments, make related domain professional and technical personnel can realize or use the utility model.Multiple modification to these embodiments will be conspicuous concerning those skilled in the art, and defined General Principle can realize under the situation of spirit that does not break away from the utility model or scope in other embodiments among this paper.Therefore, the utility model will can not be restricted to these embodiments shown in this paper, but will meet and principle disclosed herein and features of novelty the wideest corresponding to scope.