CN1046476A - Apparatus for application of coatings by gas detonation - Google Patents

Abstract

This equipment comprises spray tube (1) and coupled spraying plating powder meter (2), blast initiation parts (3), the system (5) of the bubbling device (4) of spray tube (1) and supply spray tube (1) working gas, and system (5) contains gas mixer chamber (6) and to each main of main (7,8,9) (7,8,9) that this mixing chamber is supplied with mixed gas composition the pressure reducer of placing in turn along the air feed direction (10) is arranged all, flowmeter (11), storage tank (12), orifice plate (13) and valve (14).

Description

Apparatus for application of coatings by gas detonation

This invention belongs to part and assembly spraying plating to mechanism and machine with metal, pottery, and the equipment of oxide, nitride, boride and other dusty material coating that is to say, belongs to the equipment of application of coatings by gas detonation coating.

To the equipment part that is operated under strong abrasive wear and the fretting wear condition, spraying plating is the most effective scope of application of this invention with the wearing coat.

Equipment part in being operated in corrosive medium (acids, highly basic, lotus property solution, seawater), spraying plating is with anticorrosive property coating, and in order to prevent, with coating, be to use another field of this invention to the surperficial spraying plating of discharger and electrode at the electroerosion of connecting heavy current circuit inch.

Improve the speed of service of machine, power and productivity ratio will cause air velocity, the increase of operating temperature and pressure, and to the increasing of the basic load and the shock loading of machine construction, this can cause increasing greatly the metal consumption of machine.

Utilizing protective coating is the metal consumption that reduces structure, guarantees that the part of machine construction has the high abrasion degree, high mechanical properties, high impact toughness, the solution of highly corrosion resistant.

In the method for existing spraying plating coating, the application of coatings by gas detonation method is occupied special status, and the advantage of this method is the adhesion strength height (25～30Kg/mm of coating and base-material ²), packing height (porosity is less than 1%), part is distortion and warpage not, and can be to any base-material spraying plating with dusty material arbitrarily.

In existing method, have only the explosion method can be on the matrix of carbide tungsten thing chromium compounds and titaniferous compound, spraying plating is with the cermet carbide alloy, and the character of the character of coating and the similar carbide alloy that obtains with sintering process, in fact do not have difference.The coating that the gas explosion method forms can improve 9～19 times of the working lives of part, and the metal consumption 0.5-1 that reduces structure doubly.

For with gas explosion method spraying plating top layer, can use the blast spraying plating equipment, this equipment comprises the spray tube that an end is opened, this spray tube is connected with gas tank by air supply system, and fill with explosive mixture (for example, have the acetylene of oxygen, have selected component ratio).Then, utilize meter in the spray tube, to send into the consumption of Powdered depositing materials.The person in charge is sealed to air inlet, the ignition of just exploding simultaneously, is the fusing sprills particle of 500～1500m/S by the explosive speed of dispersing, with have the surface of the part of a segment distance to act on mutually in a spray tube opening the place ahead, and form coating on the surface of goods.

After spraying, use inert gas (air or nitrogen) to spray tube purge in addition, because producing, above-mentioned blast burns red explosive is lighted a gaseous mixture that rocks in spraying tin new share to avoid.The per second cycle-index that the state of cyclic operation of blast spraying plating has is 1～6.

Known a kind of equipment (A, N, Zi Weiliefu etc., " blast spraying plating table ", 1979, shipbuilding industry publishing house, Leningrad, the 216th page), wherein comprise flowmeter be housed to the system of spraying the tube air feed, the gas main of valve, pressure reducer, and the spray tube (or blender) and the air chamber of this system connectivity equipment.

Be installed in the pressure reduction that pressure reducer on the air chamber is used for adjusting the gas that enters from gas tank, and be used for guaranteeing with given flow to spray tube (or blender) supply gas composition.The stability of the air flow rate of being supplied with is relevant with the work accuracy of pressure reducer, and the stability of the whole technology operating mode of decision spraying plating coating.Because the working condition inaccuracy of pressure reducer, in the process of spraying plating coating, operating personnel want continuous land productivity to adjust the composition of explosive mixture with corresponding valve.Be used for controlling after the valve of blender and spray tube supply gas in unlatching, at first producing uncontrollable pressure at the air inlet main falls, gas unsettled outflow in the main then, this situation was both relevant with the gas pressure in main and the blender, and relevant with the flowed friction of air induction conduit.Because the volume of gas is big inadequately in the conduit, the lower part of spray tube will be inflated under the situation of the operating mode of uncontrollable pressure drop and gas unsteady flow amount, therefore, length along the spray tube, will the inhomogeneities of the gaseous mixture composition that work uses appears, to cause the parameter of explosive and the situation instability of dispersing the spraying plating powder particle like this, its consequence is the quality instability of resulting coating.

The complexity of adjusting the explosive mixture composition is owing to adjust the influence of a kind of flow of gaseous mixture composition to the remaining gas composition, and causes the flowmeter job insecurity to determine because of the pulsation operating mode of air feed.

The significant drawback of this equipment is that resulting coating lacks stable properties this is because cause in the unstability of spray tube implode process, cause that this instable reason is that the accuracy of explosive mixture composition consumption is low, levelling institute gas supplied flow complexity, on composition ground when blender or spray tin supply gas instability of flow.

The basic task of this invention, be the equipment of a kind of application of coatings by gas detonation coating of development, in this equipment, make the structure that system had to the mixing chamber air feed, the flow that can guarantee main implode gaseous mixture composition is a constant, and can control the flow of every kind of gas, and with strictness monitoring under other gas flow be related.

Being proposed of task is to solve like this, in the equipment of application of coatings by gas detonation coating, the blast initiation parts that comprise the spray tube and communicate with it, the meter of spraying plating powder and to the system of spray tube air feed, this system contains gas mixer chamber and supplies with the main of explosive mixture composition to mixing chamber, and the pressure reducer of settling in turn along the movement travel of explosive mixture composition, flowmeter and valve, according to this invention, every main is equipped with storage tank and orifice plate, press the direction of the supply of explosive mixture composition, storage tank places the back of flowmeter, and orifice plate is between storage tank and blender.

On every main, install storage tank additional, can guarantee that the variation of main internal pressure is not obvious in a range of DO of equipment work, can guarantee that like this gas flow in every main is a constant, and can guarantee the flowmeter steady operation.Pressure on every main in the storage tank should guarantee that the critical flow (speed that is had equals the velocity of sound) of gas passes through orifice plate.Under the critical flow situation, the pressure independent in the flow of gas and the mixing chamber can be eliminated the influence of the flow of a kind of gas of adjustment to other gas flow like this.

Adjusting gas flow can realize with the cross section of selecting orifice plate and the pressure that changes in the storage tank.If the pressure loss in the air induction conduit is little, then to carry out work under manually operating mode or automatic operating irrelevant for the flow of gas and equipment, like this can be under the idle situation of equipment, stipulate out necessary force value in the various mains, because the interior maximum pressure of the pressure in the storage tank and main differs and not quite.The pressure loss on the main in the short tube of connection storage tank and blender should be significantly smaller than the pressure drop on the orifice plate.

Fill astatically between the inch of spray tube in order to reduce mist, volume at the short tube between orifice plate and blender (if valve place orifice plate and blender in the middle of) on the main, the perhaps volume of the short tube between valve and blender (if orifice plate place valve and blender in the middle of), should be significantly less than the appearance of the gas share of in a circulation, sending into the spray tube.

In the optimal case of implementing this invention, the volume of holding vessel is at least than the big twice of volume of spraying tube.The mathematical analysis that gaseous mixture is filled spray tube process shows, this ratio of spray tube and storage tank volume is to be enough to guarantee that be constant with the velocity of sound to the situation down-off that the spray tube flows from storage tank at gas.

According to this invention, from the detailed description and accompanying drawing of the following example that carries out an invention, as can be seen, other purpose of this invention and advantage are to understand easily.

This equipment comprises the meter 2 of spray tube 1 and coupled spraying plating powder, the ignition parts 3 of blast, the bubbling device 4 of spray tube 1, and a system 5 that supplies with working gas to spray tube 1.The system 5 that is used for supplying with working gas contains mixing chamber 6 and three and supplies with fuel respectively, the main 7,8,9 of oxidant and diluent.On accompanying drawing, shown main 9 in detail, and main 7 and 8 is represented schematically just.Each bar of main 7,8,9 all contains the air inlet pressure reducer of settling in proper order along the mobile stroke of explosive mixture 10, flowmeter 11, storage tank 12, orifice plate 13 and valve 14, pressure reducer 10 communicate with air chamber (not shown on the figure).

The volume that storage tank 12 had exceeds twice than the volume of spray tube 1 at least.

The structure of above-mentioned all building blocks of this equipment does not influence the essence and the scope of application of this invention, and existing any structure all can be used as the structure of these parts in the present technique field.

The equipment of application of coatings by gas detonation coating can carry out work periodically.

Before the work beginning, lay the part (not shown on the figure) of wanting spraying plating apart from the certain distance of spray tube 1 opening.Often acting on the gas pressure of air chamber on the pressure reducer 10 of every main 7,8,9.In the time of a circulation, at first use device 4 purges spray tube 1, and Open valve 14 then, and storage tank 12 begins to flow to mixing chamber 6 by orifice plate 13 with dried linchpin 7,8,9 interior gases.The explosive mixture with neccessary composition that forms in mixing chamber 6 is admitted to spray tube 1.After gaseous mixture is full of spray tube 1, close the valve 14 on main 7 and 8, inert gas-diluent that utilization comes from main 9 stream was pushed from storage tank 6 explosive mixture with the regular hour to spray tube 1, spread to mixing chamber 6 from spray tube 1 to prevent blast.Then, close valve 14 on the main 9.Send into the spraying plating powder by means of meter 2 to spray tube 1, and use device 3 carries out blast initiation.Explosive disperses the spraying plating powder from 1 ejection of spray tube.These powder act on mutually with the surface of wanting the spraying plating part, and form coating after flying out from spray tube 1.Then, repeat this circulation.By means of pressure reducer 10 and flowmeter 11, can regulate the flow of every kind of gas.

Because at filling spray tube 1 inch, the flow of gas is stable, so this equipment allows to adopt regulation and control instrument and the self-adjusting typical schematic diagram that is generally used for steady air flow, to monitor and to adjust the flow of pulse pneumatic.

Claims (2)

1, application of coatings by gas detonation coating equipment comprises spray tube (1) and coupled blast initiation parts (3), spraying plating powder meter (2) and to the oxygen system (5) of spray tube (1), and air supply system (5) contains gas mixer chamber (6) and supply with the main (7 of explosive mixture composition to it, 8,9) and along the mobile stroke of explosive mixture composition at every main (7,8,9) put pressure reducer (10) flowmeter (11) and valve (14) in turn, the characteristics of this equipment are, every main (7,8,9) storage tank (12) all is housed, and orifice plate (13), direction along the supply of explosive mixture composition, storage tank (12) is placed on the back of flowmeter (11), and orifice plate (13) places between storage tank (11) and the blender (6).

2, according to claim 1, the characteristics of this equipment are that the volume that memory (12) is had is at least more than the big twice of volume than spray tube (1).

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