RU171191U1 - Device for pneumoabrasive treatment of the inner and outer surfaces of tube blanks - Google Patents

Abstract

The utility model relates to the machining of deep holes in pipe billets, in particular to the processing of pipe billets by a pneumatic abrasive medium. It can be used in the process of grinding the outer and inner surfaces of long pipes. The technical result is achieved by using a device for pneumoabrasive treatment of the inner and outer surfaces of tube blanks containing a reservoir for the working medium, and composite left and right flanges from coaxially placed outer and inner bushings mounted on the base equipped with centering recesses for basing tube blanks, and an intermediate sleeve equipped with clamping collets mi for fixing the screw, consisting of a two-body housing, made in the form of outer and inner tubes with outer and inner spirals, coaxially mounted one in another with a gap communicating with the pressure pipe. The screw is equipped with nozzles located on the body between the turns of the spirals and the nozzles on the inclined planes of the spirals of the screw, installed at an angle of 15 °, 30 ° and 45 ° to the machined surfaces of the pipe blanks, for separate supply of abrasive and compressed air. Technical result - increased productivity and quality processing.

Description

The utility model relates to the machining of deep holes in pipe billets, in particular to the processing of pipe billets by a pneumatic abrasive medium. It can be used in the process of grinding the outer and inner surfaces of long pipes.

A device for jet-abrasive treatment of bodies of revolution, comprising a cylindrical element for implementing the Coanda effect, a working chamber with a mounting place for a rotating workpiece, in the lower part of which a flat feed nozzle is mounted, on the opposite wall of the cylindrical element there is a pipe for feeding into the feed stream under the action of its own weight of the return abrasive (Pat. RU 11128, IPC B24C 3/22, publ. 16.09.1999).

The disadvantage of this device is the inability to combine the processing of external and internal surfaces, which reduces its performance.

Another disadvantage of the device is the inability to use in known form for simultaneous supply of intersecting streams of air jets and portions of dry abrasive and the inability to reflect a mixed pneumoabrasive stream when it moves in the gap between the pipes and the formation of turbulence of the stream between the turns of the screw when combined processing of the external and internal surfaces simultaneously several coaxially installed pipe blanks. The lack of such a possibility for a known device, even in the case of improvement and integration into known devices, reduces its performance.

A known installation for blasting the inner surface of pipe billets, containing a storage-consumable unit, consisting of two separately located bins, inkjet devices, inside the bunkers, and a piping system of the working fluid, with nozzles of jet devices displayed on the side surfaces with workpieces attached to them in succession , and pipelines of the working fluid connected to the internal cavity of the opposite hopper (Pat. RU 2274540, IPC V24C 3/16, publ. 04/20/2006).

The disadvantage of the installation is the impossibility of using it in a known manner to supply the flow of abrasive at the right angle when moving it with compressed air in the gap between the pipes and the formation of directional movement without swirling the flow when combining processing of the external and internal surfaces of several coaxially installed tube blanks. The lack of such a possibility in a known device reduces its performance.

A known automatic device for waterjet waterjet processing of the external and internal surfaces of parts that are bodies of revolution, made in the form of several isolated processing chambers, with a U-shaped bar conveyor passing through them, equipped with a set of nozzles with a pulp tank, fixing and clamping elements, which allows you to simultaneously install and process several parts (A.S. SU 180109, IPC V24C 3/12, publ. 11/28/1966).

The disadvantage of the installation is the impossibility of its use in a known way to reflect the flow of hydroabrasive fluid when it moves in the gap between the pipes and the formation of turbulence of the stream when combining processing of the outer and inner surfaces of several coaxially installed tube blanks.

Another disadvantage of this device is the inability to ensure turbulence in the flow of an abrasive medium moved under considerable pressure (up to 12 m) under air pressure. The absence of such a possibility in a known device reduces its technological capabilities.

A device for treating the inner surface of pipes containing a nozzle nozzle, elements for supplying a working substance and an energy carrier and a flow swirl made in the form of a sleeve with conical and curved sections on its outer surface, equipped with an axial mounting rod, a flange, elements for supplying a working substance and an input element energy carrier, while on the inner surface of the nozzle nozzle is made expanding towards the exit curved section (Pat. RU 2108903, IPC V24C 5/04, V24C 3/16, publ. 04/20/1998).

The disadvantage of this device is the impossibility of combining the processing of external and internal surfaces, which reduces its productivity, as well as the difficulty of creating a deviation of the supply stream along the entire length of the chamber and the complexity of the acceleration channel if it is necessary to process extended surfaces, such as long pipes. Since long pipes, for example, according to GOST 8731, 23270, GOST R 53383, can have a length of up to 9 m, when processing them, it is necessary to have a sufficiently extended chamber for movement processing the external and internal surfaces of the abrasive medium to create a swirling flow and its movement at different angles to the processed surface.

The disadvantage of the installation is the impossibility of its use in a known way to reflect the flow of hydroabrasive fluid when it moves in the gap between the pipes and the formation of turbulence of the stream when combining processing of the outer and inner surfaces of several coaxially installed tube blanks. The lack of such technological capabilities of the known device, in the case of integration into known devices, reduces its technological capabilities.

A device is known for hydroabrasive treatment of the inner and outer surfaces of pipe billets, comprising a reservoir for a hydroabrasive medium, pressure and drain pipelines mounted on the base of the left and right flanges with mirrored centering recesses for basing pipe billets and through holes of cylindrical shape, made with the possibility of fixing between them tube blanks of different diameters, mounted coaxially one in another (Pat. RU 152429, IPC V24C 3/02, V24C 9/00, publ. 05.27.2015).

The disadvantage of the installation is the use of a hydroabrasive medium containing water, which is unacceptable for the treatment of pipes to be coated with polymers and other protective substances.

In addition, a simple replacement in the known device of a hydroabrasive fluid (working medium) with an air mixture is not economically feasible, because To achieve satisfactory performance, you will have to create too large parameters for the speed of abrasive particles and air pressure. The lack of these features in this device reduces its economic and technological capabilities.

The closest structurally is a device for hydroabrasive treatment of the inner and outer surfaces of pipe billets, containing a reservoir for the working medium, a pressure pipe and left and right flanges mounted on the base, made of coaxially placed outer, intermediate and inner bushings equipped with clamping collets and centering recesses for basing and fixing tube billets, and a spiral screw mounted coaxially, equipped with rotation mechanisms with the possibility of reversal of the normal movement installed between the pipe blanks and coaxially with them a hollow spiral screw with an internal spiral made of elastic material with protrusions on the external and internal spiral equipped with abrasive elements (Pat. RU 159213, IPC V24C 3/02, V24C 9/00, publ. 02/10/2016).

The disadvantage of this device is the use of waterjet media: since the residual moisture interferes with further coating on the surface of the pipe blanks, the surface obtained after processing must be subjected to additional drying.

The objective of the technical solution is to develop a new high-performance device for dry processing of the inner and outer surfaces of tube blanks.

The technical result is to increase the productivity and quality of processing of the inner and outer surfaces of the tube blanks.

The technical result is achieved when using a device for pneumatic abrasive treatment of the inner and outer surfaces of pipe billets, containing a reservoir for the working medium, a pressure pipe installed on the base of the composite left and right flanges of coaxially placed outer and inner bushings equipped with centering recesses for basing the pipe billets, and an intermediate sleeve equipped with clamping collets for fixing the screw with the outer and inner spirals installed between the pipe blanks coaxially with them, rotation mechanisms made with the possibility of reverse movement of the auger, the auger consists of a two-body housing made in the form of external and internal pipes, coaxially mounted one in another with a gap communicating with the pressure pipe, and equipped with radial nozzles located between the turns of the said spirals, the inclined planes of the screw spirals are equipped with nozzles installed at an angle of 15 °, 30 ° and 45 ° to the machined surfaces of the pipe blanks, and on the opposite surfaces of the outer closed screw channels are made and internal pipes of the screw housing communicating with the nozzles of the screw spirals and with the reservoir for the working medium.

The essence of the technical solution lies in the direction of the working medium at the right angle to the surface to be treated by creating a mechanism for air distribution and distribution of dry abrasive material along the entire length of the surfaces to be treated by separately supplying the abrasive and compressed air to the desired point of contact with the surface to be treated and mixing them near the surface to be treated with air-abrasive processing of the outer and inner cylindrical surfaces of coaxially installed long pipe blanks. The abrasive is fed sequentially at an angle of 45 ° to the machined surfaces of the pipe blanks, then at an angle of 30 ° and, finally, 15 ° to the machined surfaces of the pipe blanks.

When the abrasive is fed at an angle of 45 ° to the machined inner surface of the tubular billet with a larger diameter and the outer surface of the tubular billet with a smaller diameter, the maximum mass removal of metal occurs, resulting in rough (rough) processing of the tubular billets.

When the abrasive is fed at an angle of 30 ° to the machined inner surface of the tube billet with a larger diameter and the outer surface of the tube billet with a smaller diameter, the average mass removal of metal occurs, resulting in semi-finished processing of the tube billets.

And, finally, when the abrasive is fed at an angle of 15 ° to the machined inner surface of the tube billet with a larger diameter and the outer surface of the tube billet with a smaller diameter, the minimum mass removal of metal occurs, resulting in finishing of the tube billets.

All three types of processing are carried out by one screw, which does not require laborious multiple collection and analysis of the device. At the same time, productivity and quality of surface treatment of tube billets are increased. In addition, mixing the jets of compressed and abrasive material outside the nozzle is preferable, since the passage of the already combined jets through the nozzle, as a rule, leads to its rapid wear.

The auger of the device consists of a two-body housing, external and internal spirals. The screw housing consists of an outer and an inner pipe coaxially mounted one in the other with a gap. In this case, the external spiral of the screw is located on the external pipe of the screw housing, and the internal spiral of the screw is located on the internal pipe of the screw housing. Both pipes are equipped with radial nozzles located between the coils of the spirals and facing the respective machined surfaces of the pipe blanks, and the gap between the pipes of the auger housing communicates with a pressure pipe supplying an air stream under pressure, which provides compressed air.

In addition, on the counter surfaces of the outer and inner pipes of the screw housing, closed screw channels are made for supplying dry abrasive, and the inclined planes of the internal and external spirals of the screw are provided with nozzles. Closed screw channels communicate with the reservoir for the working medium and with the nozzles of the screw spirals located at the same angle to the machined surfaces of the pipe blanks (only nozzles at an angle of 15 °, or only nozzles at an angle of 30 °, or only nozzles at an angle of 45 ° to the machined surfaces of pipe workpieces), which provides an independent supply of a working medium (abrasive) to nozzles located at different angles to the machined surfaces of the pipe blanks, and, accordingly, the possibility of sequential processing of pipe blanks wok.

Thus, during pneumatic abrasive treatment of tube billets, the separate supply of abrasive and compressed air directly to the point of contact with the surface to be treated as a result of mixing them near the surface to be machined at an angle of 45 °, 30 ° and 15 ° to the machined surfaces of the tube billets makes it possible to create an efficient air distribution and distribution of dry abrasive along the entire length of the machined surfaces, as well as the consistent implementation of roughing, semi-finishing and finishing, which, in turn, in children to improve productivity and quality of treatment of internal and external surfaces of tubular blanks.

In FIG. 1 shows a longitudinal section of a device for pneumoabrasive processing of the inner and outer surfaces of tube blanks. In FIG. 2 shows a longitudinal section of the screw. In FIG. 3 shows a scan of the plane of the spiral of the screw.

A device for pneumatic abrasive treatment of the inner and outer surfaces of tube blanks consists of a base 1 and a composite left flange 2 and a composite right flange 3 mounted on it, each of which consists of an outer 4, intermediate 5 and 6 inner bushings mounted coaxially in one another respectively. On the outer 4 and inner 6 bushings of the left 2 and right 3 flanges, centering recesses 7 are made for basing the tube stocks 8 (tube stock with a smaller diameter), 9 (tube stock with a larger diameter). In each centering recess 7 of the outer 4 and inner 6 bushings of the left flange 2, at least three spring-loaded crackers 10 are evenly spaced around the circumference.

The intermediate sleeves 5 of the left 2 and right flanges 3 are equipped with clamping collets 11 for clamping and rotating the screw, the two-body housing of which is made in the form of an outer pipe 12 and an inner pipe 13, coaxially mounted one into the other with a gap 14. The outer pipe 12 of the screw housing is provided with an external spiral 15, and the inner pipe 13 of the screw housing is provided with an internal spiral 16. The gap 14 between the pipes 12 and 13 of the screw housing communicates with a pressure air pipe (not shown in FIG.), Using a compressor to supply an air stream under pressure. The outer pipe 12 and the inner pipe 13 of the screw housing are provided with radial nozzles 17 located between the turns of the outer 15 and the inner 16 of the spirals and facing the respective machined surfaces of the pipe blanks. The nozzles 17 communicate with a gap 14 through the holes 18 in the outer 12 and inner 13 pipes of the screw housing.

The outer 15 and inner 16 spirals are equipped with nozzles 19-21 located on their inclined planes at an angle of 15 ° to the machined surfaces of the pipe blanks - nozzle 19, at an angle of 30 ° to the machined surfaces of the pipe blanks - nozzle 20 and at an angle of 45 ° to the machined surfaces tube blanks - nozzles 21.

On the counter surfaces of the outer 12 and inner 13 pipes of the screw housing, closed screw channels 22 are made, communicating with the nozzles 19-21 of the screw spirals and with the reservoir 23 for the working medium. Nozzles 19-21 communicate with closed screw channels 22 through additional intermediate channels (not shown in FIG.), Which are performed in screw spirals or inserted into hollow spirals. Each screw channel 22 connects nozzles located at the same angle to the machined surfaces of the pipe blanks (only nozzles 19, or only nozzles 20, or only nozzles 21), allowing independent supply of the working medium to nozzles (19, 20 or 21) located under different angles to the machined surfaces of the pipe blanks.

Closed screw channels 22 are formed from screw grooves made on the counter surfaces of the outer 12 and inner 13 pipes of the screw housing, closed with a durable elastic material.

The location of the nozzles 19-21 of the screw spirals at angles of 15 °, 30 ° and 45 ° to the machined surfaces of the pipe blanks provides the convergence and mixing of abrasive and compressed air from the radial nozzles 17 at the desired contact point on the machined surface.

In the outer 4 and inner 6 bushings of the left flange 2, through holes 24 are made, communicating through a pipe 25 with a reservoir 23 for the working medium.

On the left flange 2 and the right flange 3 are installed mechanisms of rotation of the auger with reversible electric motors 26.

The device operates as follows.

Before the start of pneumatic abrasive machining, the left flange 2 and the right flange 3 are spaced apart by a length exceeding the maximum length of the pipe blanks 8 and 9, as well as the length of the screw housing, which is assumed to be equal to the length of the pipe blanks.

At the same time, pipe blanks 8 and 9 are based in centering recesses 7, and the screw housing is located in collets 11 of the right flange 3. Next, a pipe clamp drive (not shown) is turned on, while the left flange 2 is shifted to the length of the pipe blanks 8 and 9. Crackers 10 under the action of springs fix tube blanks.

After that include electric motors 26, starting the mechanisms of rotation of the screw. In the process of rotation of the outer 12 and inner 13 pipes of the auger body, the abrasive and air are supplied simultaneously under pressure.

When the compressor is turned on, air under pressure is supplied through the pressure pipe to the gap 14, from where, through holes 18 and radial nozzles 17, respectively, onto the machined surfaces of the pipe blanks 8 and 9. Abrasive is supplied to the machined surfaces of the pipe blanks 8 and 9 from the reservoir using the corresponding compressor through channels 22 and nozzles 19-21 on the spirals of the screw. The flow of abrasive and air under pressure are mixed near the surface to be treated and are processed at the point of contact with the surface to be treated.

Moreover, the supply to the nozzle 19, 20 and 21 can be carried out sequentially. When the abrasive is fed into the nozzle 21, the maximum mass removal of metal occurs, as a result of which rough (rough) processing of pipe blanks is carried out. Further, when the abrasive is fed into the nozzle 20, an average mass removal of metal occurs, as a result of which the semi-finished processing of the pipe blanks is carried out. And finally, when the abrasive is fed into the nozzle 19, a minimum mass removal of metal occurs, as a result of which the tube blanks are finished.

As a result of rotation of the outer 12 and inner 13 pipes of the screw housing, the mechanical effect of abrasive particles mixed with the air flow on the machined surfaces of the pipe blanks 8 and 9 is carried out uniformly and throughout their length.

Next, the air flow in the mixture with the abrasive is removed through the through holes 24.

At the end of the pneumoabrasive surface treatment, the abrasive and air supply compressors, and the electric motors 26 turn off and remove the processed tube blanks 8 and 9.

Next, the processing process is repeated with new pipe blanks.

Processing parameters: abrasive material electrocorundum 24 A grain size M20; M40; M6Z; 8; 10; K = 20%; p _n * = 0.1 ... 0.5 MPa; L = 50 ... 150 mm; α = 15 ... 90 °; T = 0 ... 300 s.

The abrasive treatment of tube blanks installed coaxially in one package is carried out simultaneously by a multi-nozzle twin-screw screw (the screw housing consists of an outer pipe 12 with an external spiral 15 and an inner pipe 13 with an internal spiral 16) so that the abrasive mass has the ability to be fed to the surface under air pressure by joint supply of abrasive and compressed air through nozzles to the desired contact point at the surface being machined and at the right angle to the machined outer and inner surfaces of the pipe blanks 8 and 9 respectively, which allows to carry out the principle of the dry (anhydrous) purification.

In addition, the separate supply of abrasive and compressed air allows for wall sliding of the abrasive, i.e. treat using compressed air jets flooded with abrasive slurry, which improves the quality of processing.

Thus, the proposed device for pneumatic abrasive treatment of the inner and outer surfaces of tube billets with a dry abrasive under the influence of jets of a mixed mixture distributed over the machined surfaces formed at the point of contact with the said surfaces at different angles provides an increase in the productivity of the device and the processing quality of the external and internal surfaces of pipe blanks.

Claims (1)

A device for pneumatic abrasive treatment of the inner and outer surfaces of tube billets, containing a screw with an outer and inner spirals, a reservoir for the working medium, a pressure pipe, integral left and right flanges made of coaxially placed outer and inner bushings equipped with centering recesses for basing the tube billets and an intermediate sleeve equipped with clamping collets for fixing the screw with the outer and inner spirals installed between the pipe blanks coaxially with them, and rotation mechanisms made with the possibility of a reverse movement of the screw, characterized in that the screw consists of a two-body housing made in the form of an external and internal pipe coaxially mounted one into another with a gap communicating with the pressure pipe and provided with radial nozzles located between the turns of the said spirals, while the inclined planes of the screw spirals are equipped with nozzles installed at an angle of 15 °, 30 ° and 45 ° to the machined surfaces of the pipe blanks, and on opposite surfaces The outer and inner pipes of the screw housing have closed screw channels that communicate with the nozzles of the screw spirals and with the reservoir for the working medium.

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