Title of Invention

"A METHOD AND INSTALLATION FOR THE PROCESSING OF TUBES MADE OF PLASTIC"

Abstract Method for the processing of tubes made of plastic, especially PVC, obtained by extrusion, according to which a tube is brought to a molecular orientation temperature higher than ambient temperature and is subjected to biaxial stretching by radial expansion and by axial elongation, in order to obtain a bi-orientation tube having improved mechanical properties. The tube (T) is cut into elements (4) of specific length when it has just been extruded and when its temperature is higher than the molecular orientation temperature, each element constituting a blank (5) ; each blank (5) is placed in an enclosure (E) in order to be cooled there by a fluid (F) at a temperature near the molecular orientation tempera¬ture, the dwell time of the blank in the enclosure being longer than the time for producing the blank by extru¬sion; and the blank (5) is subsequently extracted from the enclosure (E) in order to undergo the processing which ensures bi-orientation.
Full Text WE CLAIM:
11.. Method for the processing of tubes made of plastic, especially PVC^
obtained by extrusion, according to which a tube is brought to a "^ -»
molecular orientation temperature higher than ambient temperature and { (V ^ is subjected to biaxial stretching by radial expansion and by axial elongation, in order to obtain a bi-orientation tube having improved mechanical properties, characterized in that:
the tube (T) is cut into elements (4) of specific length when it has just been extruded and when its temperature is higher than the molecular orientation temperature, each element constituting a blank (5);
each blank (5) is placed in an enclosure (E) in order to be cooled there by a fluid (F) at a temperature near the molecular orientation temperature, the dwell time of the blank in the enclosure being longer than the time for producing the blank by extrusion, in order to allow correct temperature setting,
and the blank (5a) is subsequently extracted from the enclosure (E) in order to undergo the processing which ensures bi-orientatioru
0 12. Method as claimed in claim/1, wherein the tube (T), just after being rt
extruded and before being cut, is cooled superficially by passing through a cooling fixture (7) having a length much shorter than that of conventional cooling fixtures.
13. Method as claimed in claim 1I or 12, wherein the tube is cut by means of a shearing operation with a guillotine-type device (6) with a blade (28).
14. Method as claimed in one of the preceding claims, wherein the fluid enclosure (E) is formed by a hot-water tank (9).
Method as claimed in claim /4 for the processing of PVC tubes, wherein the temperature of the water is near 100°C, in particular located within a range of 95°C to 98°C.
16. Method as claimed in claim K or/ 5, wherein the blanks (5) are agitated in the enclosure (E).
1 7. Method as claimed in one of the preceding claims, wherein the fluid is circulated in the enclosure, in particular in a direction parallel to the axis of the tube.
-1.Apparalus for the processing of tubes made of plastic, especially
PVC, forncarryiftg out a methed as claimed in one of claims1-to7
comprising an extruder (2) for producing a tube (T) and means (18) for " subjecting the tube to biaxial stretching by radial expansion and by axial elongation, in order to obtain a bi-orientation tube having improved mechanical properties, wherein it comprises:
cutting means (6) at the exit of the extruder (2), for delivering the tube in elements (4) of specific length when it has just been extruded and
when its temperature is higher than the molecular orientation
t temperature, each cut element constituting a blank (5);
an enclosure (E) for receiving the blanks (5) and cooling them by means of a fluid (F) at a temperature near the molecular orientation temperature, the enclosure (E) being provided for ensuring a dwell time of the blank which is longer than the time for producing the blank by extrusion, in order to allow correct temperature setting,
and means (15, 17) for extracting the blank from the enclosure in order to cause it to pass to the means (18) for carrying out biaxial stretching.
2 Inotollation as claimed in claim -8; wherein a cooling fixture (7) is provided at the exit of the extruder (2), in order to cool the tube (T) superficially and allow a clean cut of the still hot tube.

3 .Apparalus as claimed in claim -9; wherein the cutting means (6) consist of a cutting-blade device (28) of the guillotine type, in particular fastened to the cooling fixture (7).
4.Apparalus as claimed in one of Claims -8 to t0", wherein the fluid enclosure (E) is formed by a hot-water tank (9) which, in the case of the processing of PVC, is at a temperature near or equal to its boiling temperature at atmospheric pressure.
5.Apparalus as claimed in claim -H:, wherein means (10, 11, 12, 13) for circulating the fluid in the tank, in particular in the axial direction of the blanks, are provided.
5.Apparalus as claimed in claim-ir2, wherein the means (11, 12, 13) for circulating the fluid in the tank are arranged so as to inject a fluid stream along the axis of the blank (5a) which is the next to be extracted from the tank (9).
6.Apparalus as claimed in claim Ur, wherein the tank (9) comprises means (14) for setting in rotation about its axis the blank (5a) which is the next to be extracted from the tank.
7.Apparalus as claimed in claim -Hrj wherein the blanks (5) are supported in the tank (9) by transverse arms (21) mounted pivotably about an axis (22) parallel to the longitudinal direction of the blanks, and in that the arms (21) can be actuated in an alternating oscillating movement about the axis (22).
9 hi spoliation as claimed in claim 1 wherein it comprises a roller conveyor (8) arranged at the exit of the extruder, in alignment with the latter, for receiving the tube (T), and in that the fluid enclosure (E) for setting the temperature of the blank is placed on one side of the conveyor (8).

10. Apparvus as claimed in claim 4, wherein the speed of the conveyor (8) is substantially equal to the exit speed of the tube (T) from the extruder (2), and in that it may be variable around this condition in order to overthicken (or underthicken) the tube blank (T) locally.
18. Method of producing a tube of improved mechanical properties substantially hereinbefore described with reference to and as illustrated in the accompanying drawings.
19.Apparatus for the processing of tubes substantially hereinbefore described with reference to and as illustrated in the accompanying drawings.





WE CLAIM:
11.. Method for the processing of tubes made of plastic, especially PVC^
obtained by extrusion, according to which a tube is brought to a "^ -»
molecular orientation temperature higher than ambient temperature and { (V ^ is subjected to biaxial stretching by radial expansion and by axial elongation, in order to obtain a bi-orientation tube having improved mechanical properties, characterized in that:
the tube (T) is cut into elements (4) of specific length when it has just been extruded and when its temperature is higher than the molecular orientation temperature, each element constituting a blank (5);
each blank (5) is placed in an enclosure (E) in order to be cooled there by a fluid (F) at a temperature near the molecular orientation temperature, the dwell time of the blank in the enclosure being longer than the time for producing the blank by extrusion, in order to allow correct temperature setting,
and the blank (5a) is subsequently extracted from the enclosure (E) in order to undergo the processing which ensures bi-orientatioru
0 12. Method as claimed in claim/1, wherein the tube (T), just after being rt
extruded and before being cut, is cooled superficially by passing through a cooling fixture (7) having a length much shorter than that of conventional cooling fixtures.
13. Method as claimed in claim 1I or 12, wherein the tube is cut by means of a shearing operation with a guillotine-type device (6) with a blade (28).
14. Method as claimed in one of the preceding claims, wherein the fluid enclosure (E) is formed by a hot-water tank (9).
Method as claimed in claim /4 for the processing of PVC tubes, wherein the temperature of the water is near 100°C, in particular located within a range of 95°C to 98°C.
16. Method as claimed in claim K or/ 5, wherein the blanks (5) are agitated in the enclosure (E).
1 7. Method as claimed in one of the preceding claims, wherein the fluid is circulated in the enclosure, in particular in a direction parallel to the axis of the tube.
-1.Apparalus for the processing of tubes made of plastic, especially
PVC, forncarryiftg out a methed as claimed in one of claims1-to7
comprising an extruder (2) for producing a tube (T) and means (18) for " subjecting the tube to biaxial stretching by radial expansion and by axial elongation, in order to obtain a bi-orientation tube having improved mechanical properties, wherein it comprises:
cutting means (6) at the exit of the extruder (2), for delivering the tube in elements (4) of specific length when it has just been extruded and
when its temperature is higher than the molecular orientation
t temperature, each cut element constituting a blank (5);
an enclosure (E) for receiving the blanks (5) and cooling them by means of a fluid (F) at a temperature near the molecular orientation temperature, the enclosure (E) being provided for ensuring a dwell time of the blank which is longer than the time for producing the blank by extrusion, in order to allow correct temperature setting,
and means (15, 17) for extracting the blank from the enclosure in order to cause it to pass to the means (18) for carrying out biaxial stretching.
2 Inotollation as claimed in claim -8; wherein a cooling fixture (7) is provided at the exit of the extruder (2), in order to cool the tube (T) superficially and allow a clean cut of the still hot tube.

3 .Apparalus as claimed in claim -9; wherein the cutting means (6) consist of a cutting-blade device (28) of the guillotine type, in particular fastened to the cooling fixture (7).
4.Apparalus as claimed in one of Claims -8 to t0", wherein the fluid enclosure (E) is formed by a hot-water tank (9) which, in the case of the processing of PVC, is at a temperature near or equal to its boiling temperature at atmospheric pressure.
5.Apparalus as claimed in claim -H:, wherein means (10, 11, 12, 13) for circulating the fluid in the tank, in particular in the axial direction of the blanks, are provided.
5.Apparalus as claimed in claim-ir2, wherein the means (11, 12, 13) for circulating the fluid in the tank are arranged so as to inject a fluid stream along the axis of the blank (5a) which is the next to be extracted from the tank (9).
6.Apparalus as claimed in claim Ur, wherein the tank (9) comprises means (14) for setting in rotation about its axis the blank (5a) which is the next to be extracted from the tank.
7.Apparalus as claimed in claim -Hrj wherein the blanks (5) are supported in the tank (9) by transverse arms (21) mounted pivotably about an axis (22) parallel to the longitudinal direction of the blanks, and in that the arms (21) can be actuated in an alternating oscillating movement about the axis (22).
9 hi spoliation as claimed in claim 1 wherein it comprises a roller conveyor (8) arranged at the exit of the extruder, in alignment with the latter, for receiving the tube (T), and in that the fluid enclosure (E) for setting the temperature of the blank is placed on one side of the conveyor (8).

10. Apparvus as claimed in claim 4, wherein the speed of the conveyor (8) is substantially equal to the exit speed of the tube (T) from the extruder (2), and in that it may be variable around this condition in order to overthicken (or underthicken) the tube blank (T) locally.
18. Method of producing a tube of improved mechanical properties substantially hereinbefore described with reference to and as illustrated in the accompanying drawings.
19.Apparatus for the processing of tubes substantially hereinbefore described with reference to and as illustrated in the accompanying drawings.




Documents:

2551-del-1997-abstract.pdf

2551-del-1997-claims.pdf

2551-del-1997-correspondence-others.pdf

2551-del-1997-correspondence-po.pdf

2551-del-1997-description (complete).pdf

2551-del-1997-drawings.pdf

2551-del-1997-form-1.pdf

2551-del-1997-form-13.pdf

2551-del-1997-form-19.pdf

2551-del-1997-form-2.pdf

2551-del-1997-form-3.pdf

2551-del-1997-form-4.pdf

2551-del-1997-form-5.pdf

2551-del-1997-form-6.pdf

2551-del-1997-gpa.pdf

2551-del-1997-petition-137.pdf

2551-del-1997-petition-138.pdf

abstract.jpg


Patent Number 214972
Indian Patent Application Number 2551/DEL/1997
PG Journal Number 10/2008
Publication Date 07-Mar-2008
Grant Date 19-Feb-2008
Date of Filing 09-Sep-1997
Name of Patentee ALPHACAN
Applicant Address 12/18 AVENUE DE LA JONCHERE ELYSEE 2, F-78170 LA CELLE SAINT-CLOUD, FRANCE.
Inventors:
# Inventor's Name Inventor's Address
1 BERNARD PREVOTAT 30 BOULEVARD EXELMANS, F-78150 LE CHESNAY, FRANCE
2 JEAN-JACQUES ACKET CHEMIN DU VERNAY, F-58000, CHAALLUY, FRANCE
PCT International Classification Number B29C 47/90
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 9611705 1996-09-26 France