Rotational flow spray gun head, spraying method of rotational flow spray gun head and shot blasting machine

Abstract

The invention provides a rotational flow spray gun head and a spraying method thereof and a shot blasting machine, and relates to the technical field of casting surface treatment device.According to the rotational flow spray gun head, a flow guide groove is machined in an inner hole of a gun head body in the axial direction, the flow guide groove is in a spiral line shape and penetrates through the air inlet end of the gun head body to the air outlet end of the gun head body, and one end of a connecting sleeve is connected with a shot blasting pipe; the other end of the sleeve is sleeved outside the gun head body; external threads are arranged on the outer portion of the step face of the side, close to the gun head body, of the connecting sleeve, the connecting nut is arranged on the threads of the connecting sleeve in a sleeving mode and used for locking and fixing the gun head body and the connecting sleeve, and the technical problem that in the prior art, a direct injection type spray gun head can only cover the area right opposite to the axis of a nozzle, and dead angles exist is solved; the technical effects that the high-speed rotational flow compressed air and the steel shots are subjected to high-speed rotational flow scouring and impacting in the complex inner cavity of the workpiece, the shot blasting efficiency is improved, and the production cost is saved are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of casting surface treatment devices, in particular to a cyclone spray gun head, a spraying method thereof and a shot blasting machine. BACKGROUND

[0002] Shot blasting technology is mainly applied to the cleaning of the inner cavity of complex workpieces such as automobile engine cylinder block castings.

[0003] The mainstream equipment currently used in the industry for shot blasting of workpieces has a straight spray type spray gun head as the core executive component. This type of spray gun head is composed of a shot blasting pipe, a straight cylinder nozzle body and a connecting component, and has no special internal flow guide structure. Its working mode is as follows: high-pressure air enters the spray gun head from the shot blasting pipe, directly drives the steel shots to move linearly along the nozzle axis, and impacts the surface of the workpiece at high speed, thereby realizing impurity flushing and surface treatment through the kinetic energy of the steel shots. This structure is simple in design and low in manufacturing cost.

[0004] However, the straight spray type spray gun head has the following problems: the steel shots move linearly, can only cover the area directly opposite the nozzle axis, and is prone to forming shot blasting dead angles in non-straight areas such as inner cavity corners and deep cavities, thereby increasing the risk of waste sand residue; and in order to compensate for the insufficient cleaning of the dead angles, the cleaning effect needs to be optimized by prolonging the shot blasting time and increasing the amount of steel shots, which directly causes waste of steel shot materials, increases the energy consumption of high-pressure air sources, and reduces the production rhythm, thereby affecting the overall production efficiency. SUMMARY

[0005] The present application aims to provide a cyclone spray gun head, a spraying method thereof and a shot blasting machine to alleviate the technical problem of the straight spray type spray gun head in the prior art, which can only cover the area directly opposite the nozzle axis and has dead angles.

[0006] The cyclone spray gun head provided by the present application comprises a gun head body, a connecting sleeve and a connecting nut. The inner hole of the gun head body is axially machined with a flow guide groove, the flow guide groove is in the shape of a spiral line, the flow guide groove penetrates the air inlet end to the air outlet end of the gun head body, one end of the connecting sleeve is connected with the shot blasting pipe, and the other end of the connecting sleeve is sleeved on the outside of the gun head body; an external thread is arranged on the step surface of the side of the connecting sleeve close to the gun head body, and the connecting nut is sleeved on the thread of the connecting sleeve to lock and fix the gun head body and the connecting sleeve.

[0007] Further, the number of flow guide grooves is 2-4, and the plurality of flow guide grooves are evenly distributed along the circumferential direction of the inner hole of the gun head body.

[0008] Further, the transverse cross-sectional shape of the flow guide groove is semicircular or U-shaped, the slot width of the flow guide groove is 1-3 mm, and the groove depth is 0.5-0.8 mm.

[0009] Further, the connecting nut is larger in diameter at the end close to the connecting sleeve than at the end close to the gun head body, for clamping the gun head body.

[0010] Further, the inner hole of the gun head body is further provided with a guide section, which is located at the air inlet end of the flow guide groove and is trumpet-shaped.

[0011] The present application provides a jetting method of the rotational flow gun head, which uses the rotational flow gun head described above and comprises the following steps: Step 1, connecting and fixing the gun head body to the shot blasting pipe of the shot blasting machine through the connecting sleeve, and locking and sealing through the connecting nut; Step 2, starting the shot blasting machine, so that the high-pressure air carrying the steel shots enters the inner hole of the gun head body along the shot blasting pipe; Step 3, when the high-pressure air and the steel shots flow through the flow guide groove, the rotational flow is formed under the guidance of the flow guide groove, and the steel shots are driven to be in a rotational flow state; Step 4, the high-pressure air and the steel shots in the rotational flow state are jetted from the air outlet end of the gun head body to the inner cavity of the workpiece, and the shot blasting cleaning of the inner cavity of the workpiece is completed through the rotational impact and scouring of the steel shots on the surface of the inner cavity.

[0012] Further, in step 2, when the depth of the inner cavity of the workpiece is not less than 50 mm, the high-pressure air pressure is set to 0.6-0.8 MPa, and the steel shot particle size is 1-2 mm; when the depth of the inner cavity of the workpiece is less than 50 mm, the high-pressure air pressure is set to 0.4-0.6 MPa, and the steel shot particle size is set to 0.5-0.9 mm.

[0013] The present application provides a shot blasting machine, which comprises the rotational flow gun head described above as a nozzle.

[0014] Advantages: The rotational flow gun head, the jetting method thereof and the shot blasting machine provided by the present application can provide a stable rotational flow guide path for the high-pressure air and the steel shots through the through-type spiral line flow guide groove machined along the axial direction in the inner hole of the gun head body. Compared with the traditional straight jetting type gun head, the rotational flow gun head can greatly expand the coverage range of the steel shots in the inner cavity of the workpiece, especially for the areas such as the corners of the complex inner cavity and the deep cavity which are prone to form dead angles, the steel shots in the rotational flow state can realize omnidirectional scouring through rotational impact, effectively solving the problem of incomplete cleaning of the traditional straight jetting technology, and indirectly reducing material loss and energy consumption without the need to compensate for the cleaning defects by prolonging the shot blasting time and increasing the shot blasting amount. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort based on these drawings.

[0016] Figure 1 The structural schematic diagram of the cyclone spray gun head provided by the embodiment of the present application is shown in the figure. Figure 2 The working schematic diagram of the cyclone spray gun head provided by the embodiment of the present application is shown in the figure. Figure 3 The flow chart of the spraying method of the cyclone spray gun head provided by the embodiment of the present application is shown in the figure.

[0017] Figure legend: 1-gun head body; 2-connection sleeve; 3-connection nut; 4-flow guide groove; 5-guide section. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, not all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments in the present application without creative effort are within the scope of protection of the present application.

[0020] It should be noted that: similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0021] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings or the orientation or positional relationship commonly used when the product of the present application is used, and are merely for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0022] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components must be absolutely horizontal or overhanging, but can be slightly inclined. For example, "horizontal" only means that it is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0023] In the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "arrangement", "installation", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0024] Some embodiments of the present application will be described in detail below with reference to the accompanying drawings. The following examples and features in the examples can be combined with each other without conflict.

[0025] Example 1 As shown in Figure 1 , Figure 2 The present application provides a cyclone spray gun head, which comprises a gun head body 1, a connecting sleeve 2 and a connecting nut 3. The inner hole of the gun head body 1 is axially machined with a flow guide groove 4, the flow guide groove 4 is in the shape of a spiral line, the flow guide groove 4 penetrates the air inlet end to the air outlet end of the gun head body 1, one end of the connecting sleeve 2 is connected with the shot blasting pipe, and the other end is sleeved on the outside of the gun head body 1; The outer thread is arranged on the stepped surface of the connecting sleeve 2 close to the gun head body 1, and the connecting nut 3 is sleeved on the thread of the connecting sleeve 2, which is used to lock and fix the gun head body 1 and the connecting sleeve 2.

[0026] Specifically, the inner hole is provided at the center axis of the gun head body 1, the inner wall of the inner hole is processed with the flow guide groove 4 in the axial direction, that is, parallel to the center axis of the gun head body 1, and the flow guide groove 4 is in the form of a continuous and uniform spiral line, the starting end of which is located on the inner wall of the air inlet end of the gun head body 1 receiving high-pressure air and steel balls, the ending end extends to the inner wall of the air outlet end of the gun head body 1 spraying air flow and steel balls, and penetrates through the axial two ends of the gun head body 1, forming a complete spiral guide channel; the connecting sleeve 2 is used as an intermediate connecting component, one end of which is fixedly connected with the external shot blasting pipe through threads, ensuring that the high-pressure air and steel balls in the shot blasting pipe can stably enter the inside of the connecting sleeve 2; the other end of the connecting sleeve 2 is wrapped around the outside of the gun head body 1 in a gap fit manner, and the wrapping position corresponds to the outer side wall of the gun head body 1 close to the air inlet end, so that the air inlet end port of the gun head body 1 is completely aligned with the internal channel of the connecting sleeve 2, ensuring that the airflow can pass through without obstruction; in addition, the outer side wall of the side close to the gun head body 1 of the connecting sleeve 2 is integrally formed with an annular stepped surface, the outer peripheral wall of the stepped surface is processed with external threads, and the inner hole of the connecting nut 3 is provided with internal threads matched with the external threads, the connecting nut 3 is sleeved into the air outlet end side of the gun head body 1, and finally screwed at the external threads of the connecting sleeve 2, by tightening the connecting nut 3, the end face can abut against the outer side step of the gun head body 1, and then the gun head body 1 and the connecting sleeve 2 are locked and fixed in the axial direction, avoiding the relative displacement of the two under the impact of high-pressure airflow.

[0027] The spiral line of the flow guide groove 4 can provide uninterrupted spiral flow guidance for high-pressure air and steel balls, after the airflow enters the air inlet end of the gun head body 1, it can continuously obtain rotating power along the spiral flow guide 4, ensuring that it still maintains a stable and strong spiral flow state when being sprayed out of the air outlet end of the gun head body 1, providing a core guarantee for the dead angle-free cleaning of complex workpiece cavities (engine cylinder deep cavities, corners); the coaxial alignment of the gun head body 1 and the connecting sleeve 2 can be quickly realized, avoiding airflow turbulence caused by assembly deviation; the stepped surface not only provides axial limiting for the connecting nut 3 to prevent deformation of the part caused by excessive tightening, but also enhances the sealing performance of the connection to avoid the decrease of kinetic energy of the steel balls caused by high-pressure air leakage; the locking mode of the threaded connection does not require special disassembly tools, and only needs to loosen the connecting nut 3 in the later stage to replace the worn gun head body 1.

[0028] Embodiment 2 On the basis of the embodiment 1 of the present application, the number of the flow guide grooves 4 is 2-4, and the plurality of flow guide grooves 4 are uniformly distributed along the circumferential direction of the inner hole of the gun head body 1.

[0029] The transverse cross-sectional shape of the flow guide groove 4 is in the form of a semicircle or a U shape, the slot width of the flow guide groove 4 is 1-3 mm, preferably 2 mm, and the groove depth is 0.5-0.8 mm, preferably 0.6 mm.

[0030] The connecting nut 3 has a larger diameter at one end close to the connecting sleeve 2 than at the other end close to the gun head body 1, so as to clamp the gun head body 1.

[0031] The inner hole of the gun head body 1 is further provided with a guide section 5 located at the air inlet end of the flow guide groove 4 and having a horn shape.

[0032] Specifically, the flow guide groove 4 is axially arranged on the inner wall of the inner hole of the gun head body 1, and the number of the flow guide grooves 4 is 2-4, and all the flow guide grooves 4 are evenly distributed at equal angles along the circumferential direction of the inner hole of the gun head body 1 with the center axis of the inner hole of the gun head body 1 as the symmetry reference, so as to ensure the uniformity of the distances between the grooves; meanwhile, the transverse section of the flow guide groove 4 is a smooth semicircle or U shape perpendicular to the axial section of the gun head body 1, and has no sharp edge, and the slot width of the flow guide groove 4 ranges from 1 mm to 3 mm, and the groove depth ranges from 0.5 mm to 0.8 mm. The inner hole of the connecting nut 3 is designed to have a variable diameter, and the diameter of the inner hole at one end close to the connecting sleeve 2 is larger than that at the other end close to the gun head body 1; when the connecting nut 3 is screwed onto the outer thread of the connecting sleeve 2, the inner wall of the connecting nut 3 tightly abuts against the outer wall of the gun head body 1, so as to clamp and fix the gun head body 1. In addition, the inner hole of the gun head body 1 is integrally formed with a guide section 5 at the air inlet end of the flow guide groove 4, i.e. at the air inlet side close to the connecting sleeve 2, and the guide section 5 is directly communicated with the air inlet end of the flow guide groove 4, and the guide section 5 has a horn shape as a whole, and the diameter of the guide section 5 at one end close to the shot blasting pipe is larger, and gradually decreases towards the flow guide groove 4, so as to form a smooth transition channel.

[0033] The flow guide groove 4 can reduce the air flow resistance through the semicircular or U-shaped section, and avoid air flow turbulence caused by sharp structures, and the preferred slot width of 2 mm and groove depth of 0.6 mm can ensure that the steel shots are not blocked due to the too narrow groove, and the structure strength of the gun head body 1 is not weakened due to the too deep groove, so as to finally form a uniform and stable rotational flow.

[0034] Example 3 As shown in Figure 3 The present application provides a jetting method of the rotational flow gun head, which uses the rotational flow gun head of example 1 or 2, and includes the following steps: Step 1, connecting and fixing the gun head body 1 with the shot blasting pipe of the shot blasting machine through the connecting sleeve 2, and locking and sealing through the connecting nut 3. Specifically, before the shot blasting operation is performed, the assembly of the cyclone spray gun head and the shot blasting machine is first completed: one end of the connecting sleeve 2 is coaxially fixed with the shot blasting pipe of the shot blasting machine to ensure that the high-pressure air and the steel shots in the shot blasting pipe can smoothly enter the inside of the connecting sleeve 2; then the other end of the connecting sleeve 2 is sleeved on the outer side wall of the gun head body 1 near the air inlet end in a clearance fit manner, so that the air inlet end port of the gun head body 1 is completely aligned with the internal passage of the connecting sleeve 2, avoiding blockage when the airflow flows; finally, the connecting nut 3 is sleeved from the air outlet end side of the gun head body 1, so that the inner hole thereof engages with the external threads near the side of the gun head body 1, and the connecting nut 3 is tightened clockwise until the end face thereof tightly abuts against the outer stepped surface of the gun head body 1, so that the axial fixation of the gun head body 1 and the connecting sleeve 2 is realized through the thread locking force, and the clearance fit of the two is used for sealing to prevent the subsequent high-pressure air from leaking from the connecting part.

[0035] Step 2, start the shot blasting machine, so that the high-pressure air carrying the steel shots enters the inner hole of the gun head body 1 along the shot blasting pipe; when the depth of the inner cavity of the workpiece is not less than 50 mm, the high-pressure air pressure is set to 0.6-0.8 MPa, preferably 0.8 MPa. The steel shot particle size is 1-2 mm, preferably 1.5 mm; when the depth of the inner cavity of the workpiece is less than 50 mm, the high-pressure air pressure is set to 0.4-0.6 MPa, preferably 0.6 MPa, and the steel shot particle size is set to 0.5-0.9 mm, preferably 0.8 mm.

[0036] Specifically, the core shot blasting parameters are adjusted according to the depth of the inner cavity of the workpiece to be cleaned; if the depth of the inner cavity of the workpiece is ≥50 mm (such as the deep oil channel and long gas channel of the engine cylinder), the high-pressure air pressure output by the shot blasting machine needs to be set to 0.6-0.8 MPa, preferably 0.8 MPa, which can ensure that the high-pressure air has sufficient thrust to drive the steel shots to overcome the airflow resistance in the deep cavity and reach the deep inner cavity. Meanwhile, steel shots with a particle size of 1-2 mm are selected to ensure smooth flow. If the depth of the inner cavity of the workpiece is <50 mm (such as the shallow cavity of the cylinder and the short connecting hole), the high-pressure air pressure is adjusted to 0.4-0.6 MPa, preferably 0.6 MPa, and steel shots with a particle size of 0.5-0.9 mm are selected.

[0037] Step 3, when the high-pressure air and the steel shots flow through the guide groove 4, a rotating airflow is formed under the guidance of the guide groove 4, which drives the steel shots to rotate in a cyclone state. Specifically, the mixed medium of high-pressure air and steel shots enters the inner hole of the gun head body 1, directly contacts and enters the guide groove 4, and is forced to change the direction of movement by the spiral groove wall when flowing along the guide groove 4 in the axial direction, because the guide groove 4 is in a spiral line shape and penetrates the air inlet end to the air outlet end of the gun head body 1. The high-pressure air first generates rotational movement along the spiral trajectory of the guide groove 4, forming a clockwise spiral airflow. At the same time, the steel shots move along the spiral trajectory synchronously with the airflow under the combined action of the thrust of the high-pressure air and the friction of the guide groove 4, forming a stable rotational flow state.

[0038] Step 4, the high-pressure air and steel shots in the rotational flow state are sprayed from the air outlet end of the gun head body 1 to the inner cavity of the workpiece, and the shot blasting cleaning of the inner cavity of the workpiece is completed through the rotational impact and scouring of the steel shots on the surface of the inner cavity.

[0039] Specifically, after the high-pressure air and steel shots in the rotational flow state are sprayed at high speed from the air outlet end of the gun head body 1 to the inner cavity of the workpiece, the rotational airflow drives the steel shots to make a circular diffusion movement along the inner cavity wall of the workpiece, so that the steel shots can not only cover the axial directly facing area of the inner cavity, but also can penetrate into the "dead angle" of the corner, step and deep hole of the inner cavity which is difficult to reach by the traditional straight spraying type gun head, so as to avoid impurities remaining. The steel shots will impact the surface of the inner cavity in a multi-angle and continuous manner in the rotation process, and the steel shots will change the impact direction under the action of rotational inertia, so as to not only remove the loose waste sand attached to the surface, but also polish stubborn burrs through rotational friction; at the same time, the high-pressure rotational airflow can also carry out the impurities impacted and fallen from the inner cavity in time, so as to prevent the impurities from being attached to the surface of the workpiece again, and realize the thorough cleaning of the inner cavity of the workpiece.

[0040] Embodiment 4 The shot blasting machine provided by the application comprises the rotational flow gun head in the embodiments 1 or 2 as a spray head.

[0041] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the application, but not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the application.

Claims

1. A swirling spray gun head, characterized in that, include: Gun head body (1), connecting sleeve (2) and connecting nut (3); The inner hole of the gun head body (1) is machined with a guide groove (4) along the axial direction. The guide groove (4) is spiral-shaped and passes through the air inlet end to the air outlet end of the gun head body (1). One end of the connecting sleeve (2) is connected to the shot peening pipe, and the other end is sleeved on the outside of the gun head body (1). The connecting sleeve (2) has an external thread on the outer side of the stepped surface near the gun head body (1). The connecting nut (3) is sleeved on the thread of the connecting sleeve (2) to lock and fix the gun head body (1) and the connecting sleeve (2).

2. The swirl spray gun head according to claim 1, characterized in that, The number of the guide grooves (4) is 2 to 4, and the multiple guide grooves (4) are evenly distributed along the circumferential direction of the inner hole of the gun head body (1).

3. The swirl spray gun head according to claim 2, characterized in that, The transverse cross-sectional shape of the guide groove (4) is semi-circular or U-shaped, and the groove width of the guide groove (4) is 1-3mm and the groove depth is 0.5-0.8mm.

4. The swirl spray gun head according to claim 1, characterized in that, The diameter of the connecting nut (3) near the connecting sleeve (2) is larger than the diameter of the end near the gun head body (1), and is used to clamp the gun head body (1).

5. The swirl spray gun head according to claim 1, characterized in that, The inner hole of the gun head body (1) is also provided with a guide section (5), which is located on the air inlet side of the guide groove (4) and is horn-shaped.

6. A spraying method for a swirling spray gun head, characterized in that, This method uses the swirl spray gun head according to any one of claims 1-5, and includes the following steps: Step 1: Connect and fix the gun head body (1) to the shot peening pipe of the shot peening machine through the connecting sleeve (2), and lock and seal it through the connecting nut (3); Step 2: Start the shot peening machine so that high-pressure air carries steel shot along the shot peening pipe into the inner hole of the gun head body (1); Step 3: When the high-pressure air and steel shot flow through the guide groove (4), a rotating airflow is formed under the guidance of the guide groove (4), which drives the steel shot to a swirling state; Step 4: High-pressure air in a swirling state and steel shot are sprayed from the air outlet of the gun head body (1) into the inner cavity of the workpiece. The shot blasting of the inner cavity is completed by the rotating impact and scouring of the steel shot on the inner cavity surface.

7. The spraying method according to claim 6, characterized in that, In step 2, when the inner cavity depth of the workpiece is not less than 50mm, the high-pressure air pressure is set to 0.6-0.8MPa and the steel shot particle size is 1-2mm; when the inner cavity depth of the workpiece is less than 50mm, the high-pressure air pressure is set to 0.4-0.6MPa and the steel shot particle size is set to 0.5-0.9mm.

8. A shot peening machine, characterized in that, The nozzle includes the swirl spray gun head as described in any one of claims 1-5.

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