TITLE OF THE INVENTION: A Method for Coating an Inner Surface of a Tube with a Curable Layer.
TECHNICAL FIELD OF THE INVENTION The present invention generally relates to a method for allowing to coat an inner surface of a pipe with a curable coating or provide a solid lining and where the method utilizes an arrangement being displaceable through the pipe and having a nozzle, and more particularly to such a method that is adapted to initially be capable of coating an inner wall portion of a pipe with a viscous layer of a plastic material or a reinforced plastic material and that is allowed to cure in order to form a solid coating or lining.
In such a method-adapted application, the arrangement and the nozzle comprises a rotatably arranged shaft, a disc attached to the shaft, which disc prefer- ably is assigned a plate-like shape and as such formed with a bottom part and an edge or border connecting thereto, in order to thereby allowing to define an inner space.
In such a method-adapted application, the arrangement and the nozzle compri- ses a rotatably arranged shaft, a disc attached to the shaft, which disc preferably is assigned a plate-like shape and as such formed with a bottom part and an edge or border connecting thereto, in order to thereby allowing to define an inner space.
The viscous properties of said plastic material are adapted to be capable of being supplied to said inner space as a consistent compound while said disc is given a rotary motion, in order to, by means of the same rotary motion, allowing to distribute portions of plastic material, at least such material resting on the disc,
as a viscous layer against adjacent inner wall sections of the pipe, the inner wall portion of which is to be coated with a solid lining after curing.
The invention is based on the fact that the utilized plastic compound should ha- ve such viscous properties that it, as separated portions of plastic material, can be thrown outwardly and against and without significant loss stick against the inner wall sections of the pipe and/or a wall portion provided thereby.
When the viscous material lies against the inner surface of the pipe, it should be allowed to cure and forms in that connection an ever more solid coating over time, serving as said solid lining.
BACKGROUND OF THE INVENTION Methods and arrangements of the above-mentioned nature, in order to be capable of coating an inner wall portion of a pipe with a layer of different materials, are previously known in a plurality of different embodiments.
The same methods and arrangements have in common that they, via an arran- gement with a rotary nozzle, should be capable of throwing material portions radially outwards, where the material portions should have a "highly viscous" structure, and against and stick to the inner wall sections of the pipe, with stuck material portions being allowed to cure to a solid layer to form a water tight lining.
As a first example of the background art and the technical field to which the invention relates, and from which device the method according to the present invention can be regarded to constitute a direct further development, is more closely shown and described in a patent publication US-A-5 951 761.
The method-related peculiarities and significant features associated with the present invention will be more closely described below by means of the device, shown and described in the above-mentioned US patent publication, however it should be taken into consideration that the peculiarities of the invention very
well may come to use in other arrangements having devices provided with nozzles, such as those that are described in the patent publication US-A-4 414 918, alternatively in the Austrian patent publication AT-B-383 053.
Also the method utilized by masons when render is thrown up against a vertical surface by means of a trowel, and the render, by the given motion of the trowel and the render, is got to stick against the surface without too large loss, belongs to the prior art.
Hence, it is previously known that in said lining and/or in mentioned mason application give the material portions an adapted kinetic energy, when the hits thereof strike against the inner wall of the pipe alternatively the vertical surface, and with said energy, on that occasion, being selected within the limits that is required for the material portions to stick as a viscous layer.
By the phrase "viscous layer" and "highly viscous structure" for the material portions, it is meant a material having a viscosity falling within defined limits.
In the practical application of the present invention and upon the utilization of a plastic material in the form of polyester, in a JCJ viscosimeter, at large shear rates, values of 250 to 350 cp have been measured, and in a Brockfield RVF viscosimeter, at small shear rates, values of 20 000 to 25 000 cp have been measured.
SUMMARY OF THE PRESENT INVENTION TECHNICAL PROBLEM
Considering the circumstance that the technical considerations, which a person skilled in the art of the relevant technical field has to do in order to be able to present a solution of one or more posed technical problems, are, on one hand, initially a necessary understanding of the measures and/or the sequence of measures that have to be taken, and, on the other hand, a necessary selection of the means that is/are required, then, in this connection, the subsequent techni-
cal problems would be relevant in bringing forth the present subject matter of the invention.
While taking prior art into consideration, as it has, inter alia, been described ab- ove, it should, therefore, be seen as a technical problem to be capable of providing such method-related conditions to be capable of, from a rotary disc or plate included in an arrangement having a nozzle, adjustably throwing out portions of plastic material of appurtenant energy up, outwardly and against the inner wall sections of a pipe so that the material portions will stick against the inner wall portion of the pipe, and subsequent to a curing allow the formation of a solid layer or the provision a solid lining.
In that connection, it should be seen as a technical problem to be capable of realising the significance of and the advantages associated with allowing to con- centrate the estimations, for this purpose, to the criterion of the centrifugal force and then preferably theoretical centrifugal forces.
In that connection, there is a technical problem of being capable of providing a theoretically range of centrifugal force, which in the first place should be depen- dent on selected circumferential speeds of the disc in the known way, and in the second place inversely dependent on a radius assigned to the disc.
Moreover, in an application mentioned above, there is a technical problem to be capable of realizing that a viscous coating thickness on the inside a pipe dep- ends on a number of selected and co-ordinated criteria.
Hence, there is a technical problem to be capable of realising the significance of and the advantages associated with allowing to select a method where, for this purpose, material portions given the theoretical kinetic energy can be adapted within a strictly selected range.
In addition, there is a technical problem to be capable of realising the significance of and the advantages associated with allowing to provide such method-related conditions that material portions, detached by the rotatable disc, and the in-
stantaneous viscosity thereof should be possible to be related to a selected speed of rotation of the disc.
Moreover, there is a technical problem to be capable of realizing the significan- ce of and the advantages associated with allowing to provide such conditions that material portions, detached by the rotatable disc, and the instantaneous viscosity thereof should be possible to be related to a selected circumferential speed of the disc.
Furthermore, there is a technical problem to be capable of realising the significance of and the advantages associated with allowing to provide such regulating conditions within the method taught that the material portions advantageously should be capable of having a viscosity corresponding to a mushy consistency.
Moreover, there is a technical problem to be capable of realizing the significance of and the advantages associated with allowing to provide such adjustable conditions that an occurring distance, between the periphery of the rotatable disc and the adjacent inner wall section attributed to the pipe, should be regar- ded in relation to a selected viscosity of the material portions, a selected circumferential speed of the rotatable disc and a selected centrifugal force.
There is a technical problem to be capable of realizing the significance of and the advantages associated with allowing to provide such method-related condi- tions that the speed of displacement of a nozzle axially through the pipe not only should be adapted to a selected thickness of the lining inner viscous layer but also to instantaneous and selected viscosity and selected circumferential speed of the disc.
Hence, there is a technical problem to be capable of realising the significance of and the advantages associated with allowing to provide such adjustable method related conditions that a verified uneven structure of the inner wall portion of the pipe should be allowed to be decisive for a selected speed of rotation and a selected circumferential speed of the disc, a selected viscosity of the material por-
tions and/or a selected speed of displacement of the nozzle axially through the pipe.
Moreover, there is a technical problem to be capable of realizing the significan- ce of and the advantages associated with allowing to provide such method-related and adjustable conditions that an axially and/or radially fed volume of plastic material, carried and supported by the rotatable disc and an inner space assigned to the disc, should be so large and adjustable that it extends towards a border assigned to the disc, in which border one or more slots and/or one or more holes are formed, for a detachment of small successive viscous material portions, each one of which should be thrown out by occurring centrifugal forces up against the inner wall sections of the pipe.
Moreover, there is a technical problem to be capable of realizing the significan- ce of and the advantages associated with allowing to provide such method-adapted and regulating conditions that the effective volume of material, carried and supported by the rotatable disc and the inner spaces thereof, should be so large that it extends towards and if required overflows an upper border edge.
Moreover, there is a technical problem to be capable of realizing the significance of and the advantages associated with allowing to provide such method-related and adjustable conditions that formed slots and/or holes are adapted in the orientations and dimensions thereof for allowing to detach thrown-out viscous material portions depending on a selected speed of rotation, a selected circumferential speed of the disc, a selected viscosity of detached viscous material portions and/or a selected distance between the periphery of the disc and the inner wall sections of the pipe.
In addition, there is a technical problem to be capable of realising the significan- ce of and the advantages associated with allowing to provide such method-related conditions that a first viscous material layer applied to the pipe or a number of consecutive material layers should be capable of forming a fully covering and/or even, or at least substantially a fully covering and/or even, outer surface,
even if the inner wall portion of the pipe with the wall sections thereof would be highly uneven.
Hence, there is a technical problem to be capable of realising the significance of and the advantages associated with allowing successive material portions, which are to form the applied viscous material layer, to be composed of a pure plastic material or more preferably a plastic material reinforced in various ways.
Furthermore, there is a technical problem to be capable of realising the signifi- cance of and the advantages associated with, via method-related measures, allowing a selected cross-sectional area of said disc to be adapted to a selected cross-section of said pipe and the inner wall portion thereof.
In that connection, there is a technical problem of being capable of realizing the significance of and the advantages associated with allowing such a selected cross-sectional area of said disc or plate to be adapted to cover less than 35 % of the selected cross-section of said pipe, with said values in the first place being related to a disc or plate and a pipe that are assigned circular cross-sections.
It should also be seen as a technical problem of being capable of realizing the significance of and the advantages associated with allowing the cross-sectional area of the disc to be adapted to cover and exceed 5 % of the selected cross- section of said pipe.
Then, as for the bottom part assigned to disc, it should also be seen as a technical problem of being capable of realizing the significance of and the method- related regulating advantages that become associated with allowing said bottom part to be plane and slightly cone-shaped upward and a final border to be orien- ted perpendicularly to or substantially perpendicularly to the periphery of said bottom part.
THE SOLUTION
The present invention relates to a method for allowing a coating of the inner surface or wall portion of a pipe with a solid material layer as a tight lining.
For this, an arrangement, led axially through the interior of the pipe, will be uiti- lazed, having an appurtenant nozzle, through which nozzle, by means of a rotatably arranged disc, viscous material portions are thrown, assigned different centrifugal forces and/or different kinetic energies, in order to allowing to form, on individual wall sections, a viscous layer of a plastic material or a reinforced plastic material depending on the axially directed motion and the speed of the arrangement and the nozzle through the interior of the pipe and the size of the Pipe-
Subsequent to the application against the wall sections forming the wall portion, the same plastic material should be allowed to cure time-wise to said solid material layer, serving as said lining.
More particularly, said rotatably arranged disc may be formed with a bottom part and an edge or border connecting thereto, in order to thereby allowing to define an inner, upwardly open, space, serving as a reservoir of said viscous plastic material.
In that connection, the plastic material is adapted to be supplied to said inner space close to a rotation axis assigned to the disc.
In order to be capable of solving one or more of the above-mentioned technical problems, according to the method it is taught that the radius of the disc to said edge or border and a circumferential speed given to the disc should be adapted mutually so that centrifugal forces of thrown-out material portions will have a theoretical value that falls between "m 1 500" and "m * 80 000" N, where "m" intends to represent the mass of the material portion.
As proposed embodiments, falling within the scope of the invention, further it is taught that the centrifugal force of the material portion is selected between "m *
1 500" N and "m x 30 000" N, alternatively that the centrifugal force of the material portion is selected between "m x 3 000" N and "m 40 000" N, alternatively that the centrifugal force allotted of the material portion is selected between "m x 5 000" N and "m x 76 000" N, depending on selected diameter of the disc.
Further it is taught that said disc advantageously should be assigned a diameter of more than 20 mm, however preferably less than 60 mm.
More particularly, said disc should be assigned a diameter of between 20 mm and 40 mm, such as between 20 mm and 30 mm, alternatively between 30 mm and 40 mm.
According to the invention, it is taught that it should be possible to give the disc a circumferential speed of between 4 m/s and 50 m/s, preferably between 4 m/s and 20 m/s, alternatively between 7 m/s and 25 m/s, alternatively between 12 m/s to 50 m/s.
Particularly, it is suggested that the disc is given a circumferential speed of 10 m/s to 30 m/s, at approx. 10 000 r/min.
The invention further teaches that the theoretical energy content of the material portion (kinetic energy content) should be selected between "m 8" J and "m * 1 200" J, alternatively between "m 8" J and "m x 150" J, alternatively between "m 20" J and "m x 300" J, and alternatively between "m 100" J and "m x 1 200" J.
Further, the inventive method teaches that the material portions detached by the rotatable disc are adapted depending on a selected viscosity of the viscous material related to a selected circumferential speed of the disc, and the shapes and the number of slots or holes distributed along the border and/or periphery of the disc.
The method further teaches that a distance between a periphery attributed to the rotatable disc and an adjacent inner wall section attributed to the pipe is
adapted and selected in relation to a selected viscosity of the material portions and a selected circumferential speed of the rotatable disc.
The speed of displacement of the arrangement and the nozzle in the axial direc- tion within and through the pipe is not only adapted to a desired and selected thickness of the lining inner viscous layer but also to a selected viscosity and the circumferential speed of the disc.
A present uneven surface structure of the inner wall portion of the pipe and/or wall sections adapts and determines the selection of speed of rotation and the selection of circumferential speed of the disc, the selection of viscosity of the material portions and/or the selection of an axially directed speed of displacement.
The method also utilizes that a selected material volume, carried by the rotatable disc by an inner space attributed to the disc, is adapted to be large enough so that it extends towards an upwardly extending border assigned to the disc, in which border a number of, one or more, slots and/or holes are formed for the detachment of the material portions that should be thrown out by centrifugal for- ces acting on the portions, up against the inner wall portions of the pipe.
The slots are well distributed along the border, and axially oriented and assigned a width of 0,6 to 1 ,0 mm.
The number of slots is selected to be between 4 and 8, such as 5.
Further, it is suggested that the volume of material carried by the rotatable disc and the inner space thereof is adapted to be large enough so that it will extend towards and slightly above an upper border edge.
The number and the size of formed slots and/or holes are adapted in the dimensions thereof for allowing to detach thrown-out material portions depending on a selected speed of rotation and selected circumferential speed of the disc, selec-
ted viscosity of detached material portions and/or selected distance between the periphery of the disc and the inner adjacent wall sections of the pipe.
The method relies further on the fact that a selected cross-sectional area of said disc should be adapted to be less than 35 % of selected cross-section of said pipe and the inner wall portion thereof.
More particularly, it is suggested that the cross-sectional area should be adapted to exceed 5 % of selected cross-section of said pipe and the inner wall por- tion thereof.
The invention also comprises a control unit, adapted to be capable of regulating one or more of the above-mentioned criteria on the application of a viscous layer having a predetermined thickness on wall sections next to said rotatable disc.
All or certain selected criteria are controllable via circuits and functions attributed to the control unit and upon the utilization of a central computer unit.
As an alternative, all or certain selected criteria may be manually controllable by an ocular inspection of the result attained, as of said layer of viscous plastic material and/or said solid and cured layer of plastic material or formed lining.
ADVANTAGES
The advantages that foremost can be regarded as characteristic of the present invention and the special significative features provided thereby, are that, in this way, conditions have been created in order to, via a method, in a simple and regulating way be capable of providing a homogeneous and levelling coating of the inner wall portions of a pipe, where each viscous layer of a plastic material applied in the same way but regulated will provide conditions to build on hollowing irregularities and cover holes in the wall sections of the inner pipe.
Via the method according to the provisions of the invention, particularly there is offered, via selected criteria and the centrifugal force in the first place, a regulating possibility of thereby making the application of a plurality of viscous layers of plastic material built from material portions more effective, in order to succes- sively build a tight lining.
What foremost can be regarded as characteristic of a method, in accordance with the present invention, is defined in the characterizing clause of the subsequent claim 1.
BRIEF DESCRIPTION OF THE DRAWINGS
Since the method-related peculiarities or significant features associated with the present invention are applicable upon the utilization of one, among a plurality of different available, arrangements with nozzle, by means of centrifugal forces being adapted to be capable of coating the inner wall sections or wall portions of a pipe with one or more viscous layers of a plastic material, or a reinforced plastic material, which then are allowed to cure to a solid inner lining, a presently proposed embodiment of such a selected arrangement will be described more closely for the purpose of exemplifying only, reference being made to the accompanying drawing, in order to thereby be capable of making clear the method-rela- ted fundamental conditions for the present invention, where:
Figure 1 shows a radially oriented cross-section of a pipe, the inner axially oriented wall sections of which are coated with a viscous layer of a plastic material upon the utilization of a nozzle, having a rotatable disc, and where certain of the method-related peculiarities associated with the invention have been introduced.
Figure 2 shows in side view the rotatable disc alone, partly in a cross-section.
Figure 3 shows in a perspective view the disc according to figure 2 alone,
Figure 4 shows said disc slightly enlarged in relation to figure 1 ,
Figure 5 shows schematically in planar view three different diameter-assigned discs related to four different pipe cross-sections of practical dimensions,
Figure 6 shows a table of three selected rotational speeds of three selected diameters of the discs and the values obtained in that connection of the circumferential speed of the disc as well as the theoretical values that can be calculated what concerns the value of the centrifugal force and the value of the kinetic energy of a material portion having the mass "m", and
Figure 7 shows schematically a control unit, in order to, via the same, automatically and/or manually be capable of regulating different method-related parameters and/or functions adapted to the significant features or peculiarities of the invention.
DESCRIPTION OF PRIOR ART ACCORDING TO PATENT PUBLICATION US-A-5951 761.
Referring to figures 1 to 4, there is shown an arrangement 1 of an application of an inner viscous coating 21 of a pipe 22, comprising not shown means for a fe- ed of a viscous coating material M1 (see figure 4) to and through a nozzle 7.
In appended figures, an installation for preparing a viscous coating material has not been illustrated, which via lines collects the curing agent and the proper coating compound, respectively, from containers not shown.
The compound of one of the containers is preferably polyester, in which extremely small flakes or particles of glass have been mixed in as reinforcing and wear material.
The preparation installation has means, in the form of a hose 6, for feeding the prepared coating material M1 to the nozzle 7, from which it is intended to be accumulated within an inner space 2a, as a material portion M2, in a rotatable disc 2.
By means of said rotatable disc 2, the material portion M2 will successively, as material portions M3, be spurted out and thrown out up against and stick as material portions M4 against the inner side 22a of the pipe 22 for the formation of a viscous layer 21 of the inner wall 22a of the pipe 22.
The hose 6 is led to a storage drum and wound around the same together with a cable-like means 9, which is formed from an elongate flexible member in the form of a steel-wire 9a and a sheath 9b arranged externally there around, formed to enable a rotary motion of said elongate member 9a around the longitu- dinal axis thereof and thereby drive the disc 2.
The cable-like means 9 starts from a driving means, in the form of a high-speed electric motor for rotation of a wire, which is arranged on the same frame as the storage drum and via a rotation drives said elongate steel-wire 9a inside the sheath 9b.
Further, the device comprises a second driving means, arranged on the frame, in the form of an electric motor, which, via a chain transmission, is arranged to drive the storage drum to rotation for pulling the arrangement 1 through a pipe, the inner wall sections of which are to be coated successively in order to form a lining of the wall portion.
Said installation is arranged for allowing to rotate the disc or plate 2 of the nozzle 1a around an axis 2', which is parallel to or substantially parallel to a centre axis 22' of the pipe 22 that the nozzle 1 a has been selected to move through, while material portions M3a is thrown radially outwards through notches or openings 3, 3a arranged substantially axially in the plate 2 of the nozzle, which notches or openings face against the inner wall sections 22a of the pipe.
In the border or wall 2b of the disc 2, radial and axial notches 3, 3a are present, oriented substantially parallel to the rotation axis 2' of the nozzle 1a for the formation of radial and axial openings in the border 2b.
Each one of said notches 3, 3a is arranged to bring about a distribution of the coating material M3a thrown out through respective opening in radial and/or axial direction.
More particularly, in figures 1 to 4 there is shown that the arrangement 1 with the nozzle 1a has an, at least partly, conical outer shape 2c and that said inner space 2a defining an inner wall 2a' of the nozzle 1a diverges in the direction from the central part thereof.
The substantially radially arranged openings 3, 3a are arranged as slots in the border 2b as well as short notches in the inner wall 2a', which figure 2 shows.
Further, it is taught that the space 2a of the nozzle 1a should at least circumfer- entially be delimited by a bottom 2c extending inwards from the inner wall 2a' for directing coating material M2 introduced into the space out through said ra- dial openings 3, 3a.
Also here, it is taught the possibility of allowing the feed means to be intended to feed a viscous coating material M1 forwards comprising a mixture of polyester and curing agent, and as an alternative it is taught that the mixture compri- ses flakes of glass for the achievement of a coating M4, consisting of a glass flake-reinforced polyester plastic or epoxy plastic subsequent to curing.
Further, there is taught the utilization of a means 4, for centring the arrangement 1 and the nozzle 1a in the pipe 22, the inner wall 22a of which is to be coated, having the rotation axis 2' thereof substantially in correspondence with the centre axis 22' of the pipe 22, and that said means 4 comprises a disc 4a of flexible material arranged in the direction of motion of the nozzle in front of the same, of substantially the same diameter as the inner diameter of the pipe 22,
which is arranged to abut against the inner wall of the pipe 22a for centring the nozzle 1a and the rotatable disc 2 thereof.
The figure 1 shows that the surface extension of the disc 2 in relation to the cross-sectional area of the pipe 22 has a value of 38 %.
DESCRIPTION OF PRESENTLY PROPOSED EMBODIMENT
It should then by way of introduction be emphasized that in the subsequent de- scription of a presently proposed embodiment of a method, which has the significative features associated with the invention and which is elucidated by the figures shown in the appended drawings, we have chosen terms and a particular terminology with the intention to thereby primarily allow to make evident the inventive idea.
It should, however, in this connection be taken into consideration that expressions chosen here should not be seen as limiting solely to the terms utilised and chosen here, but it should be understood that each term chosen in this manner should be interpreted so that it, in addition, comprises all technical equivalents that operate in the same or substantially the same way, in order to, in this way, enable the achievement of the same or substantially the same intention and/or technical effect.
Referring to figures 1 to 7, there are shown schematically, by means of different supplements, the fundamental conditions for the method taught according to the present invention, with the significant features and peculiarities associated with the invention generally having been concretised.
Hence, the invention comprises a method for allowing to coat the inner surface 22a or wall portion of a pipe 22 with a solid material layer M5 as a lining upon the utilization of an arrangement 1 led axially through the interior of the pipe and having an appurtenant nozzle 1a, through which nozzle, by means of a rotatably arranged disc 2, viscous material portions M3a are thrown in order to allowing to form, on individual wall sections 22a', a viscous layer M4 of a plastic material
or a reinforced plastic material depending on the axially directed motion and the speed of the arrangement 1 and the nozzle 1 a through the interior of the pipe 22 and the size of the pipe.
Subsequent to the application against the wall section and the wall portion or the inner surface 22a, the plastic material M4 should be allowed to cure time- wise to said solid material layer M5 for the formation of said lining.
Said rotatably arranged disc 2 should be formed with a bottom part 2c and an edge or border 2b connecting thereto, in order to thereby allowing to define an inner, upwardly open, space 2a, serving as a short-term reservoir for said viscous plastic material M1 and with said plastic material M1 being adapted to be supplied to said inner space 2a close to a rotation axis 2' assigned to the disc 2.
The invention intends to structure the prerequisites of coating the inner surface of the pipe 22a with a viscous material layer M4 and intends to take into consideration the centrifugal forces that become effective within the spurted-out and radially distributed material portions M3.
The material portions M3 are distributed outside the disc 2 as a fog or curtain and where individual material portions can be assumed to be assigned different speeds and are influenced by different centrifugal forces when they pass the slots 3, 3a in the disc 2 or flow over the border edge 2b.
Considering the high peripheral speeds that are suggested according to the invention, the individual detached material portions M3a from the accumulation M2 will be very small and of small strongly varying mass, because of which occurring different velocity vectors and centrifugal forces, which in practice act within separated material portions M3a, and that fall within the scope of the in- vention, should be estimated and simplified to the theoretical values of the centrifugal force and the energy content.
Particularly, it is taught that the disc 2, 20 and 200, with appurtenant radii r1, r2 and r3 to said edge or border 2b and a circumferential speed (v) assigned to the
disc 2 should be adapted mutually so that the centrifugal force "Fc" of a thrown out material portion M3a will have a theoretical value that falls between "m x 1 500" and "m x 80 000" N, where "m" intends to represent the mass of the material portion M3a.
As for the centrifugal force "Fc" of the thrown-out material portion M3a, it should be taken into consideration that the material M3 is thrown as a dense fog or curtain up against the inner surface 22a of the pipe 22 and particularly the surface section 22a', and that for the major part of the individual material portions, the action of the centrifugal force will be considerably smaller.
Figure 5 shows schematically three different discs 2, 20 and 200 of different diameters or radii r1, r2 and r3, centred around one and the same rotation axis 2', with a first disc 2 being assigned a diameter of 20 mm, a second disc 20 being assigned a diameter of 30 mm, while a third disc 200 being assigned a diameter of 60 mm, where, according to the principles of the invention, in the first place discs of smaller radius should be utilized also for pipes designated 122 and 222 having large cross-sections.
Figure 6 shows a table of three selected rotational speeds of 4 000, 10 000 and 15 000 r/min, assigned three selected diameters of 20, 30 and 60 mm of the discs 2, 20 and 200, and the accordingly obtained values of the circumferential speed (v) of the disc, the theoretical values what concerns the value of the centrifugal force (Fc) and the theoretical values of the value of the kinetic energy (E) of a material portion M3a having the mass "m".
The method according to the invention relies now on the fact that the centrifugal force of the material portion M3a should be selected between "m 1 500" N and "m 30 000" N, alternatively between "m x 3 000" N and "m 40 000" N and alternatively between "m x 5 000" N and "m 76 000" N, depending on selected disc 2, 20 and 200, respectively.
The method also offers a possibility of allowing to select said disc having each diameter value above 20 mm, alternatively each diameter value below 60 mm.
On that occasion, it should be possible to assign said disc a diameter of between 20 mm and 40 mm, such as between 20 mm and 30 mm (24 mm), alternatively between 30 mm and 40 mm, such as 35 mm.
The method comprises that it should be possible to give one of the discs 2, 20, 200 a circumferential speed of between 4 m/s and 50 m/s, such as between 4 m/s and 20 m/s, alternatively between 7 m/s and 25 m/s, as well as alternatively between 12 m/s to 50 m/s, depending on selected diameter of the disc.
More particularly, it is taught that it should be possible to give the disc a circumferential speed of 10 m/s to 30 m/s at approx. 10 000 r/min, such as between 8000 and 11 000 r/min, particularly between 10 m/s and 20 m/s.
The method according to the invention can also provide conditions of selecting the theoretical energy content (kinetic energy content) of the material portion M3a. On that occasion, here values between "m x 8" J and "m x 1 200" J as well as alternatively between "m * 8" J and "m x 150" J, alternatively between "m 20" J and "m x 300" J, alternatively between "m x 100" J and "m x 1 200" J, depending on selected diameter of the disc, are suggested.
According to the provisions of the method, the material portions M3a detached by the rotatable disc 2 should be adapted depending on a selected viscosity of the viscous material related to a selected circumferential speed (v) of the disc 2, and the shapes and the number of slots 3, 3a or holes distributed along the periphery 2b of the disc 2.
In the first place, the viscosity of the material and the material portions should be adapted to a viscosity that can be regarded to be in accordance with a mus- hy consistency.
Most particularly, the method according to the invention should be capable of taking into consideration also a distance between a periphery 2b attributed to the rotatable disc 2 and an adjacent inner wall section 22a attributed to the pipe
22. Here, the distance "d" should be adapted and selected in relation to a selected viscosity of the material portions M3a and a selected circumferential speed (v) of the rotatable disc 2.
The method according to the invention should also be capable of taking into consideration the speed of displacement in the axial direction 22' of the arrangement 1 and of the nozzle 1a within and through the pipe 22. Not only should the same speed "v1" be adapted to a selected thickness "t" of the lining inner viscous layer M4, but also to a selected viscosity and the circumferential speed (v) of the disc 2.
A present uneven surface structure of the inner wall portion of the pipe and the wall sections thereof adapts and determines the selection of speed of rotation "h" and the selection of circumferential speed (v) of the disc 2, the selection of viscosity of the material portions M3a and/or the selection of an axially directed speed of displacement "v1".
A selected material volume M2\ carried by the rotatable disc by an inner space 2a attributed to the disc 2, is adapted to be large enough so that it extends to- wards an upwardly extending border 2b assigned to the disc 2, in which a number of, one or more, slots 3, 3a and/or holes are formed, for the detachment of the small material portions M3a that should be thrown out by centrifugal forces acting on the portions, up against the inner wall portion of the pipe 22a.
The slots 3, 3a should be well distributed along the border 2b and axially oriented and usually assigned a width of 0,6 to 1,0 mm, such as about 0,8 mm and with the width being adapted to be larger than the size of mixed-in reinforcement or wear material.
The number of slots is selected to be between 4 and 8, such as 5.
More particularly, the method according to the invention allows the volume of material M2', carried by the rotatable disc 2 and the inner space thereof 2a, to
be adapted to be large enough so that it will extend towards and slightly above and flow over an upper border edge 2b'.
The method offers that the number and the size of formed slots 3, 3a and/or ho- les should furthermore be capable of being adapted in the dimensions thereof for allowing to detach thrown-out material portions M3a depending on a selected speed of rotation "h" and selected circumferential speed (v) of the disc 2, selected viscosity of detached material portions M3a and/or selected distance "d" between the periphery 2b of the disc and the inner adjacent wall sections 22a' of the pipe 22.
The method also comprises that a selected cross-sectional area of said disc 2, 20, 200 having the radii r1, r2 and r3 should be adapted to be less than 35 % of selected cross-section of said pipe (22), 22, 122, 222 and the inner wall portion thereof, such as 20-10 %.
Further, the cross-sectional area of selected disc 2, 20, 200 should be allowed to be adapted to exceed 5 % of selected cross-section of said pipe (22), 22, 122, 222 and the inner wall portion thereof.
Said disc and said pipe are assigned circular cross-sections in accordance with figure 5.
The invention also comprises a control unit 70, schematically shown in figure 7 and adapted to be capable of regulating one or more criteria mentioned above for the application of a viscous layer M4 having a predetermined thickness "t" on wall sections 22a' next to said rotatable disc 2.
All or certain selected criteria are controllable via circuits and functions attribu- ted to the control unit and preferably upon the utilization of a central computer unit.
All or certain selected criteria may as an alternative be manually controllable by an ocular inspection of the result attained, as of said layer M4 of viscous plastic
material and/or said solid and cured layer M5 of plastic material or formed lining.
The main object of the invention is, by means of different method-related adjustable parameters, to allowing to improve the throwing-out of the coating material M3 up against the inner surface section 22a' of the pipe 22 so that the same sticks to the inner surface of the pipe without significant loss, as well as being capable of regulating the amount of and the number of small, very small, material portions M3a that leave the disc or the plate 2.
The invention further teaches that a selected distance "d" between a circumferential edge 2b' attributed to the rotatable disc 2a and the adjacent inner wall portion 22a' attributed to the pipe 22 is adapted and selected in relation to a selected viscosity of the material portions M3a and selected circumferential speed (v) of the rotatable disc 2.
Further, the invention teaches that the speed of displacement "v1" of the nozzle 1a in the axial direction (22') within and through the pipe 22 not only is adapted to a selected thickness "t" of the lining inner layer M4 but also to selected visco- sity and the circumferential speed (v) of the disc 2.
A present uneven surface structure of the inner wall portion of the pipe 22a is adapted to and decisive for a selected speed of rotation "h" and a selected circumferential speed "v" of the disc 2, selected viscosity of the material portions M2, M3 and M3a and/or selected axial speed of displacement "v1".
A selected material volume M2', carried by the rotatable disc 2, should be adapted to be large enough so that it extends towards an upwardly extending border 2b assigned to the disc 2, in which a number of, one or more, slots 3, 3a and/or holes are formed for the detachment of the material portions M3a that should be thrown out by centrifugal forces acting on the portions, up against the inner wall portions 22a' of the pipe 22.
The volume of material M1 , M2, carried by the rotatable disc 2, is adapted to be so large that it will extend towards and above an upper border edge 2b'.
Formed slots 3, 3a and/or holes are adapted in the orientations and dimensions thereof for allowing to detach thrown-out material portions M3a depending on a selected speed of rotation and selected circumferential speed of the disc 2, selected viscosity of detached material portions M3a and/or selected distance "d" between the periphery 2b of the disc and the inner wall sections 22a' of the pipe.
Referring to figure 7, there is shown a control device and/or a control unit 70, whereby a possibility of regulating a number of quantities is offered.
Here, it is suggested to provide desired regulations via different settings, here- under denoted as "a" to "g". a. The speed of rotation of the disc (2) between 1 000 and 20 000 revolutions. b. The circumferential speed (v) of the disc (2) between 4 m/s and 60 m/s. c. Take into consideration the current distance ("d") between the circumfer- ential edge (2b) of the rotatable disc (2) and adjacent wall sections (22a') of the pipe (22). d. The speed of displacement (v1) of the arrangement (1) and the nozzle (1a) in the axial direction through the pipe (22). e. Present a regulation of selected controlled quantities depending on the surface structure of the inner surface (22a) of the pipe (22). f. The feeding volume (M2') carried by the rotatable disc (2). g. Take into consideration selection of slots (3, 3a) and/or holes as well as the shape and size of the slots in the rotatable disc (2).
The invention is of course not limited to the embodiment given above as example, but may be subjected to modifications within the scope of the general idea according to the invention, illustrated in the subsequent claims.
Particularly, it should be taken into consideration that each unit shown may be combined with each another unit shown within the scope in order to be able to attain the desired technical function.