CA2098219C - Cable conduit with ridged inner wall - Google Patents
Cable conduit with ridged inner wallInfo
- Publication number
- CA2098219C CA2098219C CA002098219A CA2098219A CA2098219C CA 2098219 C CA2098219 C CA 2098219C CA 002098219 A CA002098219 A CA 002098219A CA 2098219 A CA2098219 A CA 2098219A CA 2098219 C CA2098219 C CA 2098219C
- Authority
- CA
- Canada
- Prior art keywords
- cable
- conduit
- sliding ribs
- wall
- range
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G9/00—Installations of electric cables or lines in or on the ground or water
- H02G9/06—Installations of electric cables or lines in or on the ground or water in underground tubes or conduits; Tubes or conduits therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H57/00—Guides for filamentary materials; Supports therefor
- B65H57/12—Tubes
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G1/00—Methods or apparatus specially adapted for installing, maintaining, repairing or dismantling electric cables or lines
- H02G1/06—Methods or apparatus specially adapted for installing, maintaining, repairing or dismantling electric cables or lines for laying cables, e.g. laying apparatus on vehicle
- H02G1/08—Methods or apparatus specially adapted for installing, maintaining, repairing or dismantling electric cables or lines for laying cables, e.g. laying apparatus on vehicle through tubing or conduit, e.g. rod or draw wire for pushing or pulling
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G3/00—Installations of electric cables or lines or protective tubing therefor in or on buildings, equivalent structures or vehicles
- H02G3/22—Installations of cables or lines through walls, floors or ceilings, e.g. into buildings
Landscapes
- Architecture (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Engineering & Computer Science (AREA)
- Details Of Indoor Wiring (AREA)
- Insulated Conductors (AREA)
- Laying Of Electric Cables Or Lines Outside (AREA)
- Electric Cable Installation (AREA)
- Electric Cable Arrangement Between Relatively Moving Parts (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
- Flexible Shafts (AREA)
- Communication Cables (AREA)
- Steroid Compounds (AREA)
- Rigid Pipes And Flexible Pipes (AREA)
- Cable Accessories (AREA)
- Platform Screen Doors And Railroad Systems (AREA)
- Extrusion Moulding Of Plastics Or The Like (AREA)
- Accommodation For Nursing Or Treatment Tables (AREA)
- Thermotherapy And Cooling Therapy Devices (AREA)
- Compositions Of Macromolecular Compounds (AREA)
Abstract
An electrical conduit is substantially circular and is internally formed with zig-zag ridges. The ridges are angularly equispaced and have portions of constant pitch a joined at corners, and the ridges contact a cable in the conduit at regions K each defined by the formula:
Ar = 0.16b2zL K, where A = the surface of area R, equal to between 4,5mm2 and 32mm2, r = the radius of the conduit or D/2, b = the width of the contact region K, z = the number of ridges 1, and L K = axial length of each ridge straight portion.
The straight-portion pitch g in radians is equal to:
g = r'al L K
and is between 0.0o1rad and 1.2rad, radius r being equal to between 12mm and 100mm and L K is between 500mm and 10,000mm, depending on the diameter of the cable which can range from 5mm to 45mm.
Ar = 0.16b2zL K, where A = the surface of area R, equal to between 4,5mm2 and 32mm2, r = the radius of the conduit or D/2, b = the width of the contact region K, z = the number of ridges 1, and L K = axial length of each ridge straight portion.
The straight-portion pitch g in radians is equal to:
g = r'al L K
and is between 0.0o1rad and 1.2rad, radius r being equal to between 12mm and 100mm and L K is between 500mm and 10,000mm, depending on the diameter of the cable which can range from 5mm to 45mm.
Description
CABLE CONDUIT WITH RIDGED INNEB WALL
Field of the Invention The present invention relates to a cable conduit. More particularly this invention concerns such a conduit which i8 typically used underground to protect electrical wires and cables.
Back~round of the Invention As described in German patent document 3,217,401 and in US
patent~ 5,069,254 and 4,036,891 all of H. Vogelsang conduit assemblies are known comprising one or more tubes formed of a synthetic resin and interconnected transversely by longitudinally extending webs. Thus the tubes can be delivered rolled up on spools with the plurality of tubes and their webs in a flat coil. For use they are unwound, cut to length, and then bunched together to form the desired dense array of ~uxtaposed tubes through which electrical lines, e.g. wires or cables, are pulled or pushed.
In order to facilitate insertion of the cables German patent document 3,529,541 of H. Vogelsang proposes forming the inner wall of each tube with longitud~n~lly extending ridges alternating with longitnd~n~lly extending grooves. These longitud~n~lly continuous and throughgoing formations reduce the contact area between the wires or cables being inserted through them to facilitate such insertion.
A ma~or disadvantage of this arrangement is that the ridges invariably run somewhat along a helix like a screwthread due to the rotation of the worm in the extruder. These helically extending ridges impart some torsion to the electrical lines being pushed or pulled through the conduit. Hence these lines can twist up and get ~ammed, or can ~ust wind about each other to form a bulky mass.
An electrical conduit for wires or cables has also been proposed which is formed by a tube extending along a longitudinal axis and having an inner wall formed with a plurality of longitudin~lly throughgoing ridges each formed by a plurality of longitud~n~lly ~oined portions with every other portion inclined oppositely relative to the axis to the intervening portions. In other words the ridges run alternately along a right-hand helix and then a left-hand helix. Thus with this arrangement any torsion that the ridges apply to the wires or cables being pulled or pushed through the conduit will be cancelled out - 2 - 2~ ~ ~ 2 1~
from one portion to the next. In this manner there will be no twisting and b~r~n~ of the cables. The portions may be of varying pitch and may in fact be part circular. It is also possible for the portions to be substantially identical in which case they are straight and meet at corners. In this case the portions are all of the same pitch. German utility model 9,014,571 published 21 March 1991 describes such an arrangement where the portions meet at smoothly curved corners, virtually having a sinusoidal shape.
The ridges of this system are of substantially triangular cross-section. The tube has a predetermined wall thickness measured radially and the ridges have a radial height above the inner wall that is substantially less than the wall thickness. In addition the tube has a predetermined wall thickness measured radially and the ridges have an angular dimension that is substantially less than the wall thickness. The inner wall is formed between the ridges with grooves complementary to the ridges. It is possible for the ridges to be unitary with the tubing. They can also be separate elements that are applied in a separate stage so that the ridges are formed of a synthetic resin having a lower coefficient of friction than the tube.
The conduit i8 made by forcing the tube longitu~1n~11y through an ~nn~ r opening defined intern~lly by a mandrel or die itself formed with peripheral grooves that form the ridges and alternately oppositely rotating the inner tool. The rotation speed of the mandrel is varied continuously to produce ridges of varying pitch. The inner tool itself can operate without removal of material.
While these systems do offer various advantages, they still present occasionally excessive resistance to lines being pushed or pulled through them.
Sumrnary of the Invention The present invention provides an improved ridged-wall cable conduit which overcomes or at least mitigates the above-given disadvantages, that is which offers minim:~l linear resistance to an electrical line being pulled or pushed through it.
B
Field of the Invention The present invention relates to a cable conduit. More particularly this invention concerns such a conduit which i8 typically used underground to protect electrical wires and cables.
Back~round of the Invention As described in German patent document 3,217,401 and in US
patent~ 5,069,254 and 4,036,891 all of H. Vogelsang conduit assemblies are known comprising one or more tubes formed of a synthetic resin and interconnected transversely by longitudinally extending webs. Thus the tubes can be delivered rolled up on spools with the plurality of tubes and their webs in a flat coil. For use they are unwound, cut to length, and then bunched together to form the desired dense array of ~uxtaposed tubes through which electrical lines, e.g. wires or cables, are pulled or pushed.
In order to facilitate insertion of the cables German patent document 3,529,541 of H. Vogelsang proposes forming the inner wall of each tube with longitud~n~lly extending ridges alternating with longitnd~n~lly extending grooves. These longitud~n~lly continuous and throughgoing formations reduce the contact area between the wires or cables being inserted through them to facilitate such insertion.
A ma~or disadvantage of this arrangement is that the ridges invariably run somewhat along a helix like a screwthread due to the rotation of the worm in the extruder. These helically extending ridges impart some torsion to the electrical lines being pushed or pulled through the conduit. Hence these lines can twist up and get ~ammed, or can ~ust wind about each other to form a bulky mass.
An electrical conduit for wires or cables has also been proposed which is formed by a tube extending along a longitudinal axis and having an inner wall formed with a plurality of longitudin~lly throughgoing ridges each formed by a plurality of longitud~n~lly ~oined portions with every other portion inclined oppositely relative to the axis to the intervening portions. In other words the ridges run alternately along a right-hand helix and then a left-hand helix. Thus with this arrangement any torsion that the ridges apply to the wires or cables being pulled or pushed through the conduit will be cancelled out - 2 - 2~ ~ ~ 2 1~
from one portion to the next. In this manner there will be no twisting and b~r~n~ of the cables. The portions may be of varying pitch and may in fact be part circular. It is also possible for the portions to be substantially identical in which case they are straight and meet at corners. In this case the portions are all of the same pitch. German utility model 9,014,571 published 21 March 1991 describes such an arrangement where the portions meet at smoothly curved corners, virtually having a sinusoidal shape.
The ridges of this system are of substantially triangular cross-section. The tube has a predetermined wall thickness measured radially and the ridges have a radial height above the inner wall that is substantially less than the wall thickness. In addition the tube has a predetermined wall thickness measured radially and the ridges have an angular dimension that is substantially less than the wall thickness. The inner wall is formed between the ridges with grooves complementary to the ridges. It is possible for the ridges to be unitary with the tubing. They can also be separate elements that are applied in a separate stage so that the ridges are formed of a synthetic resin having a lower coefficient of friction than the tube.
The conduit i8 made by forcing the tube longitu~1n~11y through an ~nn~ r opening defined intern~lly by a mandrel or die itself formed with peripheral grooves that form the ridges and alternately oppositely rotating the inner tool. The rotation speed of the mandrel is varied continuously to produce ridges of varying pitch. The inner tool itself can operate without removal of material.
While these systems do offer various advantages, they still present occasionally excessive resistance to lines being pushed or pulled through them.
Sumrnary of the Invention The present invention provides an improved ridged-wall cable conduit which overcomes or at least mitigates the above-given disadvantages, that is which offers minim:~l linear resistance to an electrical line being pulled or pushed through it.
B
- 3 - ~7 Q ~ ~ 2 1 ~
The invention defines ~e exact relationship of the various dimensions of the conduit to reduce friction between it and the conduit to a minimum.
The invention also provides an improved method of feeding a cable through a conduit acco.~ing to the invention.
In accordance with a particularly highly engineered embodiment of the invention the conduit is substantially circ~lar, the ridges are angularly eq~is~-~e~ and have portions of constant pitch a ~oined at corners, and the ridges contact a cable in the conduit at regions K
each defined by the formula Ar = 0.16b2z~ , where A = the surface of area R, equal to between 4.5mm2 and 32mm2, r = the radius of the conduit or D/2, b = the width of the contact region K, z = ~he number of ridges 3, and ~ = asial length of each ridge straight portion. In this arrangement the straight-portion pitch g in radians is equal to:
g = ra/LK
and is between O.OOlrad and 1.2rad, radius r being equal to between 12mm and lOOmm and LR is between 500mm and lO,OOOmm, depending on the diameter of the cable which can range from 5mm to 45mm.
According to the invention the inner wall is formed between ad~acent ridges with concave inwardly open valleys that merge smoothly with the respective ridges. Furthermore the diameter of the cable, the radial height of the ridges, and the radial depth of the valleys are such that the cable will not touch the tube inner wall between the~0 crests of ad~acent ridges.
Normally the pitch a is equal to between 45~ and 340~, preferably about 180~. Furthermore the dimensions relative to a length LK ~f the ridge~cable contact regions K satisfy the equation:
Ar = 0.16b2z (0.0003r2a2 ~ LK)~
and the dimensions relative to a length LV ~f the corners satisfy the equation:
B
-_ 4 _ 2098219 Ar = 0.16b2z(0.0003r2a2 + LK)~ ~ 4 Lvbr.
The invention is based on the knowledge that a considerable reduction of pulling forces can be achieved in the above defined and dimensioned cable conduits and cables, provided that measures have been taken to replace dry friction by a friction that approximates lubricant friction, which, as is well known, has substantially lower friction coefficients than dry friction, in case of occurrence of interferingly high pulling forces during pulling work to be performed. To achieve this, no special lubricant is required according to the invention.
It has been found that such a relationship between the dimensions ensures very little friction. This is particularly true when the ridges have a radial height of between 0.3mm and 0.5mm.
According to a further feature of this invention the inner wall is formed between the ridges with grooves complementary to the ridges.
The wave length is about lOOcm and the amplitude is between one-eighth and one-fourth of the inslde diameter. The inside diameter is between 30cm and 70cm, preferably about 50cm. Normally the amplitude is between one-eighth and one-fourth of the inside diameter and the inside diameter is between 30cm and 70cm.
The method according to the invention basically comprises the step of feeding an electrical line through the conduit at such a longitudinal speed that friction between the line and the ridges partially melts the ridges so that the molten ridges act as a lubricant. It has been found that while this is technically a dry-feed system, it has less friction than the standard prior-art procedure of coating the line with a lubricant, and is a great deal easier and less messy.
Brief DescriPtion of the Drawin~s The above and other ob~ects, features, and advantages will become more readily apparent from the following, it being understood that any feature described with reference to one embodiment of the invention can be used where possible with any other embodiment and that reference numerals or letters not specifically mentioned with reference to one figure but identical to those of another refer to structure that is functionally if not structurally identical. In the accompanying drawings:
-5 ~ 2098219 Fig. 1 is a perspective view of a conduit according to the invention;
Fig. 2 is a diagrammatic view illustrating a region of contact between a conduit ridge and an electrical line or cable in the conduit;
Fig. 3 is a side view of the inside of the conduit showing an electrical line in the conduit;
Fig. 4 is a large-scale section taken along line IV--IV of Fig.
2 during feeding of the line through the conduit; and Fig. 5 is a cross-section at very large scale illustrating a conduit and cable according to the invention.
SDecific DescriDtion As seen in Figs. 1 through 5, a conduit 2 according to the invention is unitarily formed of a durable thermoplastic synthetic resin with unillustrated webs or flanges that are connected to other such conduits as described in the above-cited patent documents. This conduit tube 2 is centered on a longitudinal axis A and has an inner wall 1 that is cylindrical and also centered on the axis A and that is formed with triangular-section ridges 3 separated by complementary triangular-section grooves 9 (see Fig. 5). The ridges 3 are of basically zig-zag shape (see Fig. 2).
Figs. 2 through 5 show how a cable 10 inserted through the conduit 2 engages the ridges 3 along a strip 4 that intersects each of these ridges 3 at a rhombic or diamond-shaped contact region K. In this arrangement as seen in Fig. 3 the ridges 3 are each formed by straight portions 6 of constant pitch a meeting at corners 8. The straight portions 6 have an axial dimension LK.
According to the invention these dimensions follow the relationship:
Ar = 0.16b2zLK, where:
A = the surface of area K, equal to between 4.5mm2 and 32mm2;
r = the radius of the conduit or D/2;
b = the width of the contact region K; and z = the number of ridges 3.
Furthermore the pitch 8 in radians is equal to:
8 = ra ~OK ~ ~ 2 1 9 and is equal to between O.OOlrad and 1.2rad.
Normally radius r is equal to between 12mm and lOOmm and LK is between 500mm and lO,OOOmm, depending on the diameter of the cable 10 which can range from 5mm to 45mm. In the illustrated embodiment the pitch a is equal to about 180~.
According to a further feature of this invention as shown in Fig. 5 the ridges 3 are spaced angularly apart by a spacing s and have a radial height hR which is such that, with a cable of a given radius rc of curvature, the cable only pro~ects into the valleys 9 by a distance which comes short by a spacing Xf from the base of the valleys 9, not making contact therewith. Thus the cable 10 rides wholly on the crests of the ridges 3.
Furthermore the following equation applies to the dimension LK:
Ar = 0.16b2z(0.0003r2a2 + LK2)~
Similarly, the dimension 1/2 satisfies the equation:
Ar = 0.16b2z(0.0003.r2a2 ~ LK)~ + 4Lvbr.
With the system of this invention it has been found extremely advantageous to pull or push the cable through the conduit 2 at such a speed as to heat and fuse the crests or outer edges of the ridges in the contact zone K as shown at 8 in ~ig. 4. This produces a lubricant effect that works so long as the cable is being pulled through the conduit, but that disappears, leaving the conduit dry, once the cable is in position. The lubricant effect of the fused film 8 in the regions K is excellent, better in fact than the prior-art system of squeezing a lubricant, typically a ~oap solution into the conduit. The main advantage is that this lubricant effect is achieved all along the cable, wherever it contacts the conduit so that the prior-art problems of uniform distribution of the lubricant are wholly avoided.
Below is a Table that gives a sampling of conduits according to the invention.
209~219 TABLE
5 Aspect Designation of Conduit 32 50 ~ 110 225 x3.0 x4.6x6.3 x12.8 ~utside diameter (mm) 32.0 50.0110.0 225.0 Wall thickness t (mm) 3.0 4.6 6.3 12.8 Inside diameter D or 2r(mm) 26.0 40.8 97.4 199.4 Number z of ridges , 26 40 40 82 ., ., . , .. .. ~ ..
Ridge spacing (mm) 3.14 3.207.65 7.65 ~ ........ . . ..
Pitch angle a (~) 180 180 180 180 Ridge contact width b (mm) . 0.1 0.1 0.1 0.1 Length of ridge contact (mm) ; 1275 2000 4775 9775 Length LV ~f bights (mm) 2 2 2 2
The invention defines ~e exact relationship of the various dimensions of the conduit to reduce friction between it and the conduit to a minimum.
The invention also provides an improved method of feeding a cable through a conduit acco.~ing to the invention.
In accordance with a particularly highly engineered embodiment of the invention the conduit is substantially circ~lar, the ridges are angularly eq~is~-~e~ and have portions of constant pitch a ~oined at corners, and the ridges contact a cable in the conduit at regions K
each defined by the formula Ar = 0.16b2z~ , where A = the surface of area R, equal to between 4.5mm2 and 32mm2, r = the radius of the conduit or D/2, b = the width of the contact region K, z = ~he number of ridges 3, and ~ = asial length of each ridge straight portion. In this arrangement the straight-portion pitch g in radians is equal to:
g = ra/LK
and is between O.OOlrad and 1.2rad, radius r being equal to between 12mm and lOOmm and LR is between 500mm and lO,OOOmm, depending on the diameter of the cable which can range from 5mm to 45mm.
According to the invention the inner wall is formed between ad~acent ridges with concave inwardly open valleys that merge smoothly with the respective ridges. Furthermore the diameter of the cable, the radial height of the ridges, and the radial depth of the valleys are such that the cable will not touch the tube inner wall between the~0 crests of ad~acent ridges.
Normally the pitch a is equal to between 45~ and 340~, preferably about 180~. Furthermore the dimensions relative to a length LK ~f the ridge~cable contact regions K satisfy the equation:
Ar = 0.16b2z (0.0003r2a2 ~ LK)~
and the dimensions relative to a length LV ~f the corners satisfy the equation:
B
-_ 4 _ 2098219 Ar = 0.16b2z(0.0003r2a2 + LK)~ ~ 4 Lvbr.
The invention is based on the knowledge that a considerable reduction of pulling forces can be achieved in the above defined and dimensioned cable conduits and cables, provided that measures have been taken to replace dry friction by a friction that approximates lubricant friction, which, as is well known, has substantially lower friction coefficients than dry friction, in case of occurrence of interferingly high pulling forces during pulling work to be performed. To achieve this, no special lubricant is required according to the invention.
It has been found that such a relationship between the dimensions ensures very little friction. This is particularly true when the ridges have a radial height of between 0.3mm and 0.5mm.
According to a further feature of this invention the inner wall is formed between the ridges with grooves complementary to the ridges.
The wave length is about lOOcm and the amplitude is between one-eighth and one-fourth of the inslde diameter. The inside diameter is between 30cm and 70cm, preferably about 50cm. Normally the amplitude is between one-eighth and one-fourth of the inside diameter and the inside diameter is between 30cm and 70cm.
The method according to the invention basically comprises the step of feeding an electrical line through the conduit at such a longitudinal speed that friction between the line and the ridges partially melts the ridges so that the molten ridges act as a lubricant. It has been found that while this is technically a dry-feed system, it has less friction than the standard prior-art procedure of coating the line with a lubricant, and is a great deal easier and less messy.
Brief DescriPtion of the Drawin~s The above and other ob~ects, features, and advantages will become more readily apparent from the following, it being understood that any feature described with reference to one embodiment of the invention can be used where possible with any other embodiment and that reference numerals or letters not specifically mentioned with reference to one figure but identical to those of another refer to structure that is functionally if not structurally identical. In the accompanying drawings:
-5 ~ 2098219 Fig. 1 is a perspective view of a conduit according to the invention;
Fig. 2 is a diagrammatic view illustrating a region of contact between a conduit ridge and an electrical line or cable in the conduit;
Fig. 3 is a side view of the inside of the conduit showing an electrical line in the conduit;
Fig. 4 is a large-scale section taken along line IV--IV of Fig.
2 during feeding of the line through the conduit; and Fig. 5 is a cross-section at very large scale illustrating a conduit and cable according to the invention.
SDecific DescriDtion As seen in Figs. 1 through 5, a conduit 2 according to the invention is unitarily formed of a durable thermoplastic synthetic resin with unillustrated webs or flanges that are connected to other such conduits as described in the above-cited patent documents. This conduit tube 2 is centered on a longitudinal axis A and has an inner wall 1 that is cylindrical and also centered on the axis A and that is formed with triangular-section ridges 3 separated by complementary triangular-section grooves 9 (see Fig. 5). The ridges 3 are of basically zig-zag shape (see Fig. 2).
Figs. 2 through 5 show how a cable 10 inserted through the conduit 2 engages the ridges 3 along a strip 4 that intersects each of these ridges 3 at a rhombic or diamond-shaped contact region K. In this arrangement as seen in Fig. 3 the ridges 3 are each formed by straight portions 6 of constant pitch a meeting at corners 8. The straight portions 6 have an axial dimension LK.
According to the invention these dimensions follow the relationship:
Ar = 0.16b2zLK, where:
A = the surface of area K, equal to between 4.5mm2 and 32mm2;
r = the radius of the conduit or D/2;
b = the width of the contact region K; and z = the number of ridges 3.
Furthermore the pitch 8 in radians is equal to:
8 = ra ~OK ~ ~ 2 1 9 and is equal to between O.OOlrad and 1.2rad.
Normally radius r is equal to between 12mm and lOOmm and LK is between 500mm and lO,OOOmm, depending on the diameter of the cable 10 which can range from 5mm to 45mm. In the illustrated embodiment the pitch a is equal to about 180~.
According to a further feature of this invention as shown in Fig. 5 the ridges 3 are spaced angularly apart by a spacing s and have a radial height hR which is such that, with a cable of a given radius rc of curvature, the cable only pro~ects into the valleys 9 by a distance which comes short by a spacing Xf from the base of the valleys 9, not making contact therewith. Thus the cable 10 rides wholly on the crests of the ridges 3.
Furthermore the following equation applies to the dimension LK:
Ar = 0.16b2z(0.0003r2a2 + LK2)~
Similarly, the dimension 1/2 satisfies the equation:
Ar = 0.16b2z(0.0003.r2a2 ~ LK)~ + 4Lvbr.
With the system of this invention it has been found extremely advantageous to pull or push the cable through the conduit 2 at such a speed as to heat and fuse the crests or outer edges of the ridges in the contact zone K as shown at 8 in ~ig. 4. This produces a lubricant effect that works so long as the cable is being pulled through the conduit, but that disappears, leaving the conduit dry, once the cable is in position. The lubricant effect of the fused film 8 in the regions K is excellent, better in fact than the prior-art system of squeezing a lubricant, typically a ~oap solution into the conduit. The main advantage is that this lubricant effect is achieved all along the cable, wherever it contacts the conduit so that the prior-art problems of uniform distribution of the lubricant are wholly avoided.
Below is a Table that gives a sampling of conduits according to the invention.
209~219 TABLE
5 Aspect Designation of Conduit 32 50 ~ 110 225 x3.0 x4.6x6.3 x12.8 ~utside diameter (mm) 32.0 50.0110.0 225.0 Wall thickness t (mm) 3.0 4.6 6.3 12.8 Inside diameter D or 2r(mm) 26.0 40.8 97.4 199.4 Number z of ridges , 26 40 40 82 ., ., . , .. .. ~ ..
Ridge spacing (mm) 3.14 3.207.65 7.65 ~ ........ . . ..
Pitch angle a (~) 180 180 180 180 Ridge contact width b (mm) . 0.1 0.1 0.1 0.1 Length of ridge contact (mm) ; 1275 2000 4775 9775 Length LV ~f bights (mm) 2 2 2 2
Claims (6)
1. A cable routing device having at least one cable conduit which is made of synthetic thermoplastic material and which comprises a cable routing duct having a duct inner wall which is circular in cross-section and which has the conduit internal radius r and having sliding ribs disposed on the duct inner wall which are integrally formed from the synthetic thermoplastic material of the synthetic material conduit and which run at a predetermined angle of rotation a with respect to the internal circumference, wherein, in a cable conduit which is disposed in a straight line with a cable to be introduced, contact areas of the rib contact width b are formed between the sliding ribs and the cable sheath of the cable to be introduced, wherein the combination of the following features is put into effect;
the sliding ribs run in the form of waves and form reversal regions between sections with a constant angle of rotation;
the rib contact width b, the number z of sliding ribs distributed equidistantly over the circumference of the duct inner wall, the conduit internal radius r, and a length, which is denoted as L K, of the rib contact sections between the reversal regions satisfy the equation Ar = 0.16b2zL K, where A defines the contact area of the cable sheath on the points of intersection with the sliding ribs in the rib contact sections, and falls numerically within the range from 4.5 to 32 mm2;
the angle g, measured in radians, of the gradient of the sliding ribs measured at the duct inner wall satisfies the equation g = ra/L K
and falls numerically within the range from 0.001 to 1,2 radians;
wherein r is selected within the range from 12 to 100 mm and L K is selected within the range from 500 to 10,000 mm, and wherein the cables to be introduced have an external radius within the range from 5 to 45 mm.
the sliding ribs run in the form of waves and form reversal regions between sections with a constant angle of rotation;
the rib contact width b, the number z of sliding ribs distributed equidistantly over the circumference of the duct inner wall, the conduit internal radius r, and a length, which is denoted as L K, of the rib contact sections between the reversal regions satisfy the equation Ar = 0.16b2zL K, where A defines the contact area of the cable sheath on the points of intersection with the sliding ribs in the rib contact sections, and falls numerically within the range from 4.5 to 32 mm2;
the angle g, measured in radians, of the gradient of the sliding ribs measured at the duct inner wall satisfies the equation g = ra/L K
and falls numerically within the range from 0.001 to 1,2 radians;
wherein r is selected within the range from 12 to 100 mm and L K is selected within the range from 500 to 10,000 mm, and wherein the cables to be introduced have an external radius within the range from 5 to 45 mm.
2. A cable routing device according to claim 1, wherein the cable duct inner wall between adjacent sliding ribs has the form of a channel which is concave towards the cable duct and which extends on both sides into the ridge of the sliding ribs.
3. A cable routing device according to either one of claims 1 or 2, wherein the angle of rotation a is selected within the range between 45° and 340°, and is preferably about 180°.
4. A cable routing device according to any one of claims 1 to 3, wherein the rib contact width b, the number z of the sliding ribs equidistantly distributed over the circumference of the duct inner wall, the conduit internal radius r, the angle of rotation a and the length L K of the rib contact sections between the reversal regions satisfy the equation Ar = 0.16b2z (0.0003 r2a2+ L K2)l/2
5. A cable routing device according to any one of claims 1 to 4, wherein connecting sections of length L V are disposed between two sections with a constant angle of rotation, in which connecting sections the sliding ribs continue parallel to the conduit axis, and that the rib contact width b, the number z of the sliding ribs equidistantly distributed over the circumference of the duct inner wall, the conduit internal radius r, the angle of rotation a, the length L V of the connecting sections satisfy the equation Ar = 0.16b2z (0.0003 r2 + L K2)1/2+ 4L Vbr.
6. A method for pulling a cable into a cable conduit according to any one of claims 1 to 5, whereby a pull-in speed of the cable to be fed is so selected that contact faces are molten by friction heat, and a lubricant friction condition isprovided by the fused mass; whilst a) the sliding ribs run in waveshape and form reversal zones between sections with constant angle of rotation, b) the rib contact width b, the number z of sliding ribs equidistantly distributed over the circumference of the conduit inside wall, the tube inside radius r, and a length or rib contact sections between reversal zones, identified as L K, satisfy the equation Ar = 0.16 b2z L K, where A defines the contact face of the cable jacket at intersecting points with sliding ribs in rib contact sections, and is numerically in the range from 4.5 to 32 mm2, and c) the angle g, measured in radians, of the sliding ribs' lead, measured on the conduit inside wall, satisfies the equation g = ra / L K
and ranges numerically from 0.001 to 1.2 rad, where r in the range from 12 and 100 mm and L K is in the range from 500 and 10,000 are selected, and the cable to be fed has an outside radius in the range from 5 to 45 mm.
and ranges numerically from 0.001 to 1.2 rad, where r in the range from 12 and 100 mm and L K is in the range from 500 and 10,000 are selected, and the cable to be fed has an outside radius in the range from 5 to 45 mm.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP4219403.2-34 | 1992-06-13 | ||
| DE4219403A DE4219403A1 (en) | 1992-06-13 | 1992-06-13 | Cable guide device with at least one cable guide tube made of thermoplastic material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2098219A1 CA2098219A1 (en) | 1993-12-14 |
| CA2098219C true CA2098219C (en) | 1999-01-26 |
Family
ID=6460953
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002098219A Expired - Fee Related CA2098219C (en) | 1992-06-13 | 1993-06-11 | Cable conduit with ridged inner wall |
Country Status (30)
| Country | Link |
|---|---|
| EP (1) | EP0578959B1 (en) |
| JP (1) | JPH06311623A (en) |
| KR (1) | KR940001505A (en) |
| CN (1) | CN1041874C (en) |
| AT (1) | ATE147899T1 (en) |
| AU (1) | AU657221B2 (en) |
| BR (1) | BR9302294A (en) |
| CA (1) | CA2098219C (en) |
| CZ (1) | CZ282290B6 (en) |
| DE (3) | DE4219403A1 (en) |
| DK (1) | DK0578959T3 (en) |
| ES (1) | ES2096803T3 (en) |
| FI (1) | FI106078B (en) |
| GB (1) | GB2268002B (en) |
| GR (1) | GR3022486T3 (en) |
| HR (1) | HRP930969B1 (en) |
| HU (1) | HU214128B (en) |
| IL (1) | IL105884A (en) |
| LT (1) | LT3010B (en) |
| MY (1) | MY109227A (en) |
| NO (1) | NO304720B1 (en) |
| NZ (1) | NZ247855A (en) |
| PL (1) | PL171740B1 (en) |
| RU (1) | RU2128389C1 (en) |
| SI (1) | SI9300308A (en) |
| SK (1) | SK281827B6 (en) |
| TR (1) | TR26974A (en) |
| TW (1) | TW227618B (en) |
| UA (1) | UA41257C2 (en) |
| YU (1) | YU41193A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11815216B2 (en) | 2020-06-18 | 2023-11-14 | United Pipeline Systems, Inc. | System and method for installing pipe liners |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE29706513U1 (en) * | 1997-04-11 | 1997-06-19 | Rehau Ag + Co, 95111 Rehau | Pipe made of polymer material |
| DE19942162A1 (en) * | 1999-09-04 | 2001-03-08 | Ralph Peter Hegler | Ribbed plastic cable protecting tube manufacturing process, involves forming outer radial ribs and inner axial sliding ribs |
| CN105931703A (en) * | 2016-06-27 | 2016-09-07 | 苏州市宏业灯具设备有限公司 | Data cable capable of being fixed at multiple points |
| WO2020122761A1 (en) * | 2018-12-10 | 2020-06-18 | Михаил Викторович ДМИТРИЕВ | Tubular cable conduit |
| RU188117U1 (en) * | 2018-12-10 | 2019-03-29 | Общество с ограниченной ответственностью "ЭнергоТэк" | TUBULAR CABLE |
| WO2020139139A1 (en) * | 2018-12-26 | 2020-07-02 | Михаил Викторович ДМИТРИЕВ | Cable conduit having an asymmetrical end piece |
| RU188322U1 (en) * | 2018-12-26 | 2019-04-08 | Общество с ограниченной ответственностью "ЭнергоТэк" | ASYMMETRIC TIP CABLE |
| RU202322U1 (en) * | 2020-11-06 | 2021-02-11 | Общество с ограниченной ответственностью "ЭнергоТэк" | CABLE WIRING DEVICE |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3217401C2 (en) * | 1982-05-08 | 1985-04-11 | Dipl.-Ing. Dr. Ernst Vogelsang Gmbh & Co Kg, 4352 Herten | Cable routing assembly made of plastic with a plurality of cable routing tubes |
| EP0188531B2 (en) * | 1984-06-28 | 1999-08-11 | Arnco Corporation | Method for installing cable using an inner duct |
| DE3529541A1 (en) * | 1985-08-17 | 1987-02-26 | Vogelsang Ernst Gmbh Co Kg | Plastic cable-guidance tube |
| US5087153A (en) * | 1989-08-23 | 1992-02-11 | Arnco Corporation | Internally spiraled duct and method of installation |
| DE4016726C1 (en) * | 1990-05-24 | 1991-07-25 | Dipl.-Ing. Dr. Ernst Vogelsang Gmbh & Co Kg, 4352 Herten, De | |
| DE4031783A1 (en) * | 1990-10-07 | 1992-04-09 | Vogelsang Ernst Gmbh Co Kg | Guide for single or multiple cables - has thermoplastic tube with parallel surface ribs whose direction alternates so as to prevent producing torsion effects in cable |
| DE4124156C1 (en) * | 1991-07-20 | 1993-02-04 | Dipl.-Ing. Dr. Ernst Vogelsang Gmbh & Co Kg, 4352 Herten, De |
-
1992
- 1992-06-13 DE DE4219403A patent/DE4219403A1/en not_active Withdrawn
- 1992-07-02 DE DE9208873U patent/DE9208873U1/en not_active Expired - Lifetime
- 1992-08-28 LT LTIP146A patent/LT3010B/en not_active IP Right Cessation
-
1993
- 1993-06-02 IL IL10588493A patent/IL105884A/en not_active IP Right Cessation
- 1993-06-03 DK DK93108919.7T patent/DK0578959T3/en active
- 1993-06-03 DE DE59305113T patent/DE59305113D1/en not_active Expired - Fee Related
- 1993-06-03 ES ES93108919T patent/ES2096803T3/en not_active Expired - Lifetime
- 1993-06-03 EP EP93108919A patent/EP0578959B1/en not_active Expired - Lifetime
- 1993-06-03 AT AT93108919T patent/ATE147899T1/en not_active IP Right Cessation
- 1993-06-03 GB GB9311475A patent/GB2268002B/en not_active Expired - Fee Related
- 1993-06-07 MY MYPI93001082A patent/MY109227A/en unknown
- 1993-06-08 CZ CZ931105A patent/CZ282290B6/en not_active IP Right Cessation
- 1993-06-08 AU AU40101/93A patent/AU657221B2/en not_active Ceased
- 1993-06-08 SK SK572-93A patent/SK281827B6/en unknown
- 1993-06-09 SI SI9300308A patent/SI9300308A/en unknown
- 1993-06-09 TR TR00499/93A patent/TR26974A/en unknown
- 1993-06-09 PL PL93299262A patent/PL171740B1/en unknown
- 1993-06-10 NO NO931904A patent/NO304720B1/en not_active IP Right Cessation
- 1993-06-11 JP JP5140378A patent/JPH06311623A/en active Pending
- 1993-06-11 HR HRP4219403.2A patent/HRP930969B1/en not_active IP Right Cessation
- 1993-06-11 RU RU93046285A patent/RU2128389C1/en active
- 1993-06-11 YU YU41193A patent/YU41193A/en unknown
- 1993-06-11 NZ NZ247855A patent/NZ247855A/en unknown
- 1993-06-11 FI FI932685A patent/FI106078B/en active
- 1993-06-11 BR BR9302294A patent/BR9302294A/en not_active IP Right Cessation
- 1993-06-11 HU HU9301711A patent/HU214128B/en not_active IP Right Cessation
- 1993-06-11 KR KR1019930010596A patent/KR940001505A/en not_active Application Discontinuation
- 1993-06-11 CA CA002098219A patent/CA2098219C/en not_active Expired - Fee Related
- 1993-06-12 CN CN93107012A patent/CN1041874C/en not_active Expired - Fee Related
- 1993-06-12 TW TW082104689A patent/TW227618B/zh active
- 1993-06-18 UA UA93002784A patent/UA41257C2/en unknown
-
1997
- 1997-02-05 GR GR970400188T patent/GR3022486T3/en unknown
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11815216B2 (en) | 2020-06-18 | 2023-11-14 | United Pipeline Systems, Inc. | System and method for installing pipe liners |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |