RU2048602C1 - Production line to apply coating on lengthened cylindrical pieces - Google Patents

Abstract

FIELD: application of coatings on metal pieces. SUBSTANCE: production line of coatings application has mounted in series feeding roller conveyer, first pressing rollers support with lengthened cylindrical pieces pressing mechanism, clearing chamber, metal application chamber, second pressing rollers support, receiving rollers conveyer, located between rollers conveyers and pressing rollers supports rotation rates equalizing mechanisms. Rollers conveyers supporting rolls are located at similar angle to longitudinal axis of production line. Feeding and receiving rollers conveyers have rates exceeding rotation rates of pressing rollers supports and rates equalizing mechanism is made in the form of mounted between driving shaft of pressing rollers supports and driving shaft of rollers conveyers usually closed friction coupling of adjustable torque, that has pressing bearing and flexible member of adjustable rigidity in mechanism of its closing. This provides increase of productivity of the production line and quality of coating due to removal of gaps between pieces and uniformity of their movement and rotation with lower wearing of production line carrying members. EFFECT: increased productivity and quality. 9 cl, 8 dwg

Description

 The invention relates to devices for mechanized coating on the surface of cylindrical lengthy products and can be used for cleaning and coating by metallization or other methods on products such as pipes.

A known line for coating long products with a metallization method, containing racks for loading and unloading, cleaning and coating chambers, roller conveying devices, a working speed task mechanism located behind the coating chamber and a pressing mechanism for drive rollers of the working speed task assembly [1]
In this line, in order to close the gap between the products in the processing zone due to the difference in the speeds of the longitudinal feed of the intermediate roller support of the feeding and receiving roller tables, the rollers of the feeding and receiving roller tables are installed at an angle β greater than the angle α, the installation of the intermediate support rollers, i.e. speed setter rollers.

 This technical solution has several disadvantages.

 Due to the installation of the rollers at different angles in different sections of the pipe passage in the line, they first move at the same speed along the feed roller table, enter at that speed into the cleaning chamber and then into the metallization chamber. At this time, the front (in the direction of travel) end of the pipe is processed at a speed equal to the speed of the feed roller table. Only from the moment the front end of the pipe enters the operating speed setter, it begins to move at a given technological speed. In this case, the speed changes both the longitudinal velocity of the pipe and the speed of its rotation, since the first depends on the second and on the installation angle of the drive rollers. Therefore, one part of the pipe is processed at one speed and the other at a different speed, which leads to a deterioration in the quality of processing and uneven coating of different sections of the pipe.

 Different angles of installation of the rollers along the line lead to uneven and rapid wear of the drive rollers, which also leads to a deterioration in the quality of the coating. This is due to the fact that the pipe is simultaneously supported by drive rollers mounted at different angles, providing different longitudinal speeds. This leads to slipping of the rollers of the supply and receiving roller tables, increasing their wear, which not only requires frequent replacement of the rollers, increasing operating costs, but also destabilizes the operating conditions of the speed setter, further affecting the quality of the coating. The need for frequent replacement of rollers not only increases the operating cost of the line, but also reduces its productivity due to frequent repair downtimes.

A known line for coating long cylindrical products containing a consumable rack with a shifter, feeding and receiving roller tables with support rollers installed at an angle to the longitudinal axis of the roller tables, a cleaning chamber and a metallization chamber located at the input end of the receiving chamber are located between the feeding and receiving roller tables the roller table is a pressure roller with a mechanism for clamping the product, a ejector and a receiving rack, moreover, to improve the quality of the coating by increasing the uniformity of emescheniya products it is provided with additional presser roller-pressing products with the mechanism mounted on the outlet end of the supply roller conveyor, the support rollers and the feed nip receiving roller conveyors and roller carriages are arranged at the same angle to the longitudinal axis of the roller table [2]
The disadvantages of this line are as follows.

 The installation of the rollers of the feed and receiving rollers and rollers of the pressure rollers at the same angle to the longitudinal axis of the line, providing equal-speed movement of the products along the entire length of the line, does not ensure the movement of the products close to each other without gaps between them, which contributes to the instability of the processing of products in the working area and It is connected with the danger of shots flying out between the products and personal injuries, as well as with irreversible losses of the shot and its increased consumption. In addition, the presence of even small gaps between the products leads to a partial hit of the metallization coating on the ends of the products, which increases the complexity of stripping the ends of the products (pipes) before welding, and in the absence of preliminary stripping affects the quality of welding.

 The formation of unavoidable gaps between the products is due to the fact that even at the same speed of the products along the entire line, even the use of automatic transfer of products from the expendable rack to the feeding roller table cannot ensure a stable gap between the products not exceeding 5 mm, with an average speed of longitudinal movement of the products in the line equal to about 1000 mm / min (more than 16 mm / m) even if the minimum duration of moving the product from the rack to the roller conveyor is 2-3 s, the previous product will leave the next length of 32-48 mm and this gap will continue further along the entire length of the line. In practice, these gaps will be much larger.

 The issue of the product from the rack to the shifter and from the shifter to the roller conveyor with lead (lead) can lead to a collision of the rear end of the previous product with the front end of the subsequent one, which leads to an emergency.

 Therefore, the establishment of all the rollers at the same angle, their equal rotational speeds and the presence of an automatic translator do not solve the problem of uniform movement of products without gaps between them.

 The aim of the invention is to increase the productivity of the line and the quality of the coating by closing gaps between the products in the processing zone to increase the uniformity of movement of the products and improve the durability of the coating.

 The objectives of the invention also include simplifying the design of the line and its components by eliminating the mechanisms of movement and adjusting the device for drying and thermal degreasing of products, as well as improving the uniformity of processing and simplifying commissioning, eliminating the need for readjustment and rearrangement of technological devices (devices for drying and thermal degreasing, shot blasting apparatus, metallizer and device for applying a polymer coating (when switching from one diameter of the product to another, due to the rational location of the product, its transport elements and processing devices.

 The objectives of the invention include increasing the service life of the rollers of the transport system by reducing their wear due to slippage due to their non-synchronous rotation.

 The purpose of the invention is also the removal of the elements of the system of transportation and rotation of products subjected to wear in violation of the synchronization of rotation of the support rollers in the kinematic chain of the drive, i.e. beyond the contact area with the workpiece, and ensuring quick change of wear elements of the drive.

 This is achieved by the fact that in the proposed line, which contains successively installed feed rolls, a pressure roller with a product clamp mechanism, a cleaning chamber and a product metallization chamber, a pressure roller with a product clamp mechanism and a feed roller, and the support rollers of the feed and receiving roller tables and pressure rollers are located at one angle to the longitudinal axis of the line, the feeding and receiving roller tables are made with rotation speeds exceeding the rotation speeds of the pressure rollers, and between the rollers Ngami and the pressure equalization rolikooporami established mechanisms of their velocities on time simultaneously finding products on the roller conveyor and clamping roller carriage.

 Each mechanism for adjusting the rotation speeds of the roller tables and pressure rollers is made in the form of a continuously closed adjustable torque friction clutch installed between the drive roller shaft of the drive roller and the drive shaft of the roller table, equipped with a pressure bearing and an elastic element of adjustable stiffness in the mechanism of its closure. In the friction couples of the friction clutch, friction material is used, prone to greasing and lowering the coefficient of friction, for example, wood. The couplings are made with quick-change friction elements, which are cylindrical bodies inserted into the nests of the disk cages of the clutch in contact with the leading disks at their ends.

 The use of friction clutches for connecting on the go shafts to equalize their rotation speeds is widely known. However, it is noted that the use of a tree as a friction material can be recommended only at low speeds due to the tendency to grease and reduce the coefficient of friction. In the described mechanism, the equalization of the rotation speeds of the rollers of the roller tables and the pressure roller support the friction clutch is constantly closed, and the kinematic chain is constructed in such a way that the rollers of the roller tables and the pressure roller rotate at different speeds, and the speed of the first exceeds the speed of the second by no more than 20% the increase in resistance to rotation of the rollers of the roller tables due to, for example, the support of the product located on them in the previous one or the entry of the product into the pressure roller support, the coupling begins to kalzyvat, equalizing the speed of rotation due to the fact that the friction roller on the product more than the friction force in the clutch. Here, the presence of friction material, which is prone to salting and a decrease in the coefficient of friction, begins to play a positive role, i.e. the effect previously noted as negative. If there is a pressure bearing in the closure mechanism of the coupling and an elastic element of adjustable stiffness, the use of this effect allows the torque of the coupling to be adjusted so that it is always on the verge of slipping into slip, i.e. at a minimum level and can easily be maintained in the desired range. The elastic element of the coupling closure mechanism can have a different design: it can be made either in the form of a spring or a rubber elastic body with a screw regulator of its elasticity, or in the form of a power (for example, pneumatic) cylinder with a pressure reducing valve installed at its inlet, which controls the value pressure supplied to the power cylinder.

 The features distinguishing the claimed technical solution from the prototype also include the fact that the burner is additionally introduced between the first pressure roller support and the cleaning chamber of the drying and thermal degreasing device, the shot blasting apparatus of the cleaning chamber, the metallization chamber metallizer and the additionally introduced polymer coating device are placed in the plane located normally to the surface and passing through the points of contact of the product with the drive rollers of the pressure rollers, while the shafts drive rollers are kinematically connected with rotational drive shafts located below them (in order to free up the area between the roller supports for placement of these technological devices), and non-drive roller bearings are made interchangeable depending on the diameter of the product.

 The clamping device is made in the form of a traverse line perpendicular to the longitudinal axis, bearing a movable and fixed on it power cylinder with a clamping roller. This makes it possible to simplify the design and ensure reliable clamping of products of various diameters despite changes in the position of the product axis in the horizontal direction, due to the fact that the non-drive rollers of the pressure rollers are made interchangeable depending on the diameter of the product.

 The driven shafts of the drive rollers of the roller tables and the pressure rollers are kinematically connected to a rotation drive common to all. This eliminates the non-synchronization of their rotation, which almost always occurs when using separate drives. And the achievement of synchronism provides an increase in the quality of coating of products, since it eliminates the unevenness of their movement during processing, as well as increasing the life of the rollers by eliminating their slippage, which reduces repair costs, reduces downtime and increases its productivity.

 The distance between the pressure rollers and the number of these supports are selected so that during processing each product is exposed to at least one and not more than two pressure rollers. This makes it possible to arrange the driving rollers of the pressure rollers in the most rational way, to minimize their number and thereby reduce both the cost of the line and the energy costs of rotating and moving products in the line.

 In FIG. 1 shows the proposed line plan; in Fig.2 a section aa in Fig. 1; figure 3 section BB in figure 1 (at the location of the metallization chamber); in Fig. 4, the node I in Fig. 1 (a mechanism for equalizing the speeds of the roller tables and pressure rollers); figure 5 section bb in figure 4; in Fig.6 section GG in Fig.4; in Fig.7 section DD in Fig.5; on Fig kinematic diagram of the line.

 The line contains feeding 1 and receiving 2 live rolls, between which there is a device 3 for drying and thermal degreasing, a shot blasting apparatus 4 with a chamber 5, a metallization chamber 6 with a metallizer 7 and a chamber 8 with a device 9 for applying a polymer coating.

 Before the device 3 for drying and thermal degreasing, i.e. at the output end of the feed roller 1, and also after the polymer coating application chamber 8, i.e., at the input end of the feed roller 2, there are pressure rollers 10 and 11 with pressure mechanisms 12. Between the technological positions 3, 5, 6 and 8 non-driven roller bearings 13.

 The feed and receiving rollers 1 and 2, the pressure rollers 10 and 11, as well as the non-drive rollers 13 have stationary stationary rollers 14 and interchangeable rollers 16, adjustable in diameter of the product 15. All rollers are installed at the same angle to the longitudinal axis of the line.

 The support rollers 14 of the roller tables 1 and 2 and the pressure rollers 10 and 11 are kinematically connected to the common drive 17 through the drive shafts 18, 19, 20 and flexible links, such as V-belts 21.

 Pulleys 22 are fixed on the drive shaft 19, and pulleys 23 on the rollers 14 of the pressure rollers 10 and 11.

 The drive shafts 18 and 20 are connected to the roller tables 1 and 2 through the pulleys 24 and 25 and the flexible links 21. Moreover, the pairs of pulleys 22-23 and 24-25 are selected so that the pressure rollers 10 and 11 have a lower rotational speed than the roller tables 1 and 2.

 In other words, the kinematic scheme provides a rotation speed of the roller tables 1 and 2 that exceeds the rotation speed of the pressure rollers 10 and 11. The presence of flexible connections between the shafts 18, 19, 20 and the rollers 14 of the roller tables 1 and 2 and the pressure rollers 10 and 11 allows you to set the rollers 14 under the desired angle to the longitudinal axis of the line, depending on the diameter of the product 15. The mechanism for re-installing and securing the rollers 14 and 16 to the desired angle can have a different design.

 Between the roller tables 1 and 2 and the pressure rollers 10 and 11, mechanisms 26 for adjusting the speeds of the roller tables with the speeds of the pressure rollers are installed. Each of these mechanisms is a permanently closed adjustable torque friction clutch 27. In this case, the outer coupling half 28 of one equalization mechanism is rigidly connected to the drive shaft 17, and the inner coupling half 29 is rigidly connected to the drive shaft 18 of the rolling table 1.

 In the second equalization mechanism, the outer coupling half 28 is rigidly connected with the drive shaft 20 of the roller table 2, and the inner coupling half 29 with the drive shaft 19 of the pressure rollers 10 and 11. Between the coupling halves 28 and 29 are mounted clips 30 with friction elements 31 made in the form of cylindrical bodies made of wood non-resinous species (birch, beech, etc.). These elements interact with the friction surfaces of the inner coupling half 29, the intermediate disk 32 and the pressure plate 33. The clip 30 is connected by the coupling half 28 with sliding keys 34, and the pressure disk 33 and the intermediate disk 32 are connected to the inner coupling half 29 by a key (or slots) 35. To the pressure disk 33, a thrust bearing 36 is fitted, which is pivotally connected to a lever 39 of the coupling closure mechanism through a cage 37 carrying pins 38. The second end of the lever 39 is provided with an elastic element 40, with which a pressure screw 42, screwed into the rack 43 of the support frame of the line, interacts through the bar 41. The elastic element 40 may also have another structural embodiment, for example, in the form of an adjustable pressure pneumatic cylinder or spring, etc.

 The swing axis 44 of the lever 40 is mounted on the rack 43. The friction elements 31 can easily be replaced after wear, for which, by unscrewing the screw 42, the lever 39 is removed from the axis 44. After that, the pressure disk 33 is shifted to the left together with the clips 31 and the disk 32, using half-coupling windows 28 to push them out.

 The interchangeable rollers 16 of all the roller bearings and roller tables are fixed on the ends of the levers 45, which swing on the axles 46 and are fixed in the desired position by the fingers in the holes 47. The length of the lever 45 and the location of the swing axis 46 are selected so that when changing the diameter of the product 15 and moving the rollers 16, the center product 15 is always in the plane EE (Fig.2 and 3). This ensures that the axis of the product is in the plane EE connecting the center of the roller 14 with the center of the product, i.e. allows you to place all the technological apparatus burner of the device 3 drying and thermal degreasing, shot blasting apparatus 4, metallizer 7 and the device for applying paint 9 in the plane EE, located normally to the work surface of the product 15. This achieves a constant optimal, not requiring rearrangement, position of all these technological apparatuses, regardless of the diameter of the product, which improves the processing condition and improves its quality, and also reduces the line change-over time.

 To adjust the tension of the elastic links 21, tension rollers 48 are provided in the rotation drives of the rollers 14.

 The clamping mechanism 12 is made in the form of a traverse, perpendicular to the longitudinal axis of the line supporting the power cylinder 50, on the rod of which a pressure roller 51 is fixed, the clip of which 52 by means of a rolling pin 53 ensures its installation at an angle identical to that of the rollers 14 and 16. For movement and fixing the cylinder 50 and the roller 51, a screw 54 is provided.

 The distance between the pressure rollers 10 and 11 is less than the length of the workpiece, which ensures that each product is in the processing process by at least one pressure roller, which allows for stable and uniform rotation and movement of the products during processing.

 The line works as follows.

 The drive 17 is turned on and during the rotation of all the rollers 14, the screws 4 of the mechanisms 26 are loosened, as a result of which the couplings 27 begin to slip and the rotation of the roller tables 1 and 2 stops.

 Then, one article 15 is laid on the roller tables 1 and 2 and the screws 42 are started to be tightened until the clutch begins to transmit the minimum necessary moment for rotation and movement of the article 15 along the roller tables 1 and 2. Previously, of course, all the roller bearings were adjusted product diameter size.

 In the process of rotation and movement, the product, moving along the roller table 1 with its front end, enters the pressure roller 10, where it is pressed by the roller 51 and begins to move at a speed necessary for processing, but less than the speed of the roller table. In this case, due to slipping of the coupling 27, the speed of the roller table is equalized with the speed of the pressure roller 10 and remains equal to it until the product 15 touches at least one of the rollers 14 of the roller table 1.

 Passing through the pressure roller 10, the article 15 undergoes drying and thermal degreasing in a device 3 containing a gas burner (not shown in the drawings). Then, the article is subjected to bead-blasting in a chamber 5. After this, the chamber 5 is coated with a coating using metallizers 7. After applying the metallization layer on a still hot product, a polymer coating is applied in the chamber 8, where the coating dries due to the heat of the product itself. After exiting the chamber 8, the front end of the product enters the second pressure roller 11 and is pressed by the mechanism 12.

 In the process of moving the product through the first pinch roller 10, the roller table 1 is gradually released and the next item to be processed is laid on its free rollers, which rotates and moves along the roller table 1 at a speed set by the previous product, which is simultaneously on the roller table and in the pinch roller, which is provided by slipping of the coupling 27.

 As soon as the rear end of the product comes off the last roller table roller 14, the resistance to rotation of the roller table rollers decreases and the coupling stops slipping and tells the roller table a speed exceeding the speed of the roller support 10. As a result, the next product will catch up with the previous one and its front end will abut the rear end of the previous one, providing continuous backlash-free movement of products one after another. After the products rested against each other, the coupling 27 begins to slip again and the products move at a speed specified by the pressure roller 10. As the movement progresses, the rear end of the previous product exits the pressure roller 10 and the front end of the subsequent product enters this support. As space becomes available on the roller table, the next product is laid on it, etc.

 The processed product, leaving the chamber 8, enters the pressure roller 11 with its front end, is pressed by the mechanism 12 and moves towards the take-up roller table 2. Until the product touches the rollers of the roller table 2, it rotates at a speed exceeding the speed of the roller support 11, since low resistance coupling 27 of the second mechanism 26 of the equalization of speeds does not slip. As soon as the front end of the finished product, emerging from the pressure roller support 11, touches the rollers of the roller table 2, its rotation resistance increases and the coupling 27 starts to slip, providing the same speed of the roller table 2 and the roller support 11. After the rear end of the product leaves the pressure roller, the resistance to its movement sharply decreases, the coupling 27 ceases to slip and the roller table 2 begins to rotate at a speed exceeding the speed of the pressure roller 11. The end of the previous product is torn off from the end of the subsequent and between them, a space is formed that allows you to capture and remove the product from the roller table 2.

 If necessary, loading and unloading racks with stackers can be installed at the beginning and at the end of the line, which are not included in the subject of development and can have a wide variety of design solutions.

 The invention provides for the manufacture and operation of the line at the lowest cost with high work efficiency and good quality products. The latter is ensured not only by the design features of the line, but also by the fact that the product is thoroughly dried before metallization, thermally degreased, which improves shot blasting, eliminating the "clogging" of non-degreased sections with a shot and improving the adhesion of the metallization layer. The application of the polymer composition over the metallization coating allows, using the porosity of the latter, to provide not only its additional protection, but also an increase in the strength of the coating as a whole.

Claims (9)

 1. A LINE FOR COATING LONG-DIMENSIONAL CYLINDRICAL PRODUCTS, comprising sequentially installed feed roller, a first pressure roller support with a product pressing mechanism, a cleaning chamber and a metallization chamber, a second pressure roller and a feed roller, a feed roller table, supporting rollers of the longitudinal axis are arranged at the same angle characterized in that it is equipped with mechanisms for equalizing rotation speeds established between the roller tables and the pressure rollers.  2. The line according to claim 1, characterized in that each of the mechanisms of the equation of speeds is made in the form of a continuously closed friction clutch of adjustable torque with a pressure bearing and an elastic element of adjustable stiffness installed between the drive shaft of the rotation drive of the pressure roller support and the drive shaft of the roller table.  3. The line according to claims 1 and 2, characterized in that the friction couples of the coupling are made of friction material, prone to salting and to reduce the coefficient of friction.  4. The line according to claim 3, characterized in that the friction couples of the coupling are made of wood.  5. The line according to claims 1 to 3, characterized in that the clutch is made with replaceable friction elements.  6. The line according to claims 1 to 5, characterized in that the friction elements are made in the form of cylindrical bodies inserted into the nests of the disk cages of the coupling in contact with the leading disks at their ends.  7. The line according to claim 1, characterized in that it is provided with a burner installed between the first roller support and the cleaning chamber and a polymer coating chamber located behind the metallization chamber, while the burner, the metallization cleaning chamber and the polymer coating are located in a plane normal to the surface of the product and passing through the points of contact of the product with the leading rollers of the roller support, the roller shafts being kinematically connected with the driving shafts of the rotation drive located below them, and non-driven rollers Execute with the possibility of changes in the product depending on the diameter.  8. The line according to claims 1 and 7, characterized in that the clamping device is made in the form of a support cylinder movable and fixed on it with a clamping roller perpendicular to the longitudinal axis of the support beam line.  9. The line according to claims 1, 2 and 7, characterized in that the driven shafts of the drive rollers of the roller tables and the roller support are kinematically connected with a rotation drive common to all.

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