DESC:FIELD OF THE INVENTION
[0001] The present invention relates a blow moulded pipe, particularly plastic blow moulded pipe. More particularly, the present invention relates a method for manufacturing blow moulded pipe, wherein the blow moulded pipe obtained is having high strength, is economical and easy to manufacture. The method of the present invention enhances productivity, reduces manufacturing cost, and time, reduces chances of pipe cracking, and eliminates use of metallic ring insert.
BACKGROUND OF THE INVENTION
[0002] In the known art, extrusion blow moulding is used to manufacture hollow parts made from plastics. It is well-known to form blow-moulded pipes with one or more open ends by firstly extruding a parison or balloon of hot thermoplastic material, bringing two halves of a mould together on opposite sides of the parison and inserting a blow pin through the mould into the parison. Air is then blown into the interior of the parison through the blow pin at high pressure to inflate the thermoplastics material against the walls of the mould. After a preset time when the moulding has set, the two halves of the mould are separated, and the moulded article is released. The blow moulded pipe so obtained is allowed to cool for a time of about twenty-four hours. This cooled pipe is further processed by cutting off the balloon. Further, the method includes the steps of boring, heating of the pipe and the press fitment of a metal ring at each end of pipe.
[0003] In the known art, the outer diameter of the pipe is decided in the beginning, is controlled, and stretched accordingly based on the product profile. However, there is a thickness variation from inside of the pipe i.e., inner diameter of the pipe is non-uniform.
[0004] Further, in order to maintain the uniformity, it is known to machine the plastic pipe. This step of machining the pipe has numerous disadvantages of plastic burr, bulging of pipes during fitment of the metallic ring, and the like. The metallic ring which is supposed to provide strength to the ends of the pipe is fitted at the end of the pipes to avoid collapse of the pipes due to the tightening force of the clamps because of the excessive flexibility of the pipes.
[0005] However, the step of fitting the metallic ring at the end thereof increases the chances of cracking of the pipe during the metallic ring fitment in hot condition.
[0006] Another disadvantage of the step of metallic ring fitment is that the metallic ring may be fitted loosely which is not desired. This may lead to an additional undesired step of rework.
[0007] The above-mentioned step of fitting the metallic ring, and disadvantages related thereto lead to lower productivity, higher cost, and wastage of time.
[0008] Therefore, there is felt an acute need for providing an improved plastic pipe, which is sturdy, especially at ends, does not require fitting of the metallic ring, can be manufactured at low cost and in reduced time span.
[0009] Further, there is felt an acute need for providing a method for manufacturing the plastic pipe using blow moulding process, wherein the method is economic, has reduced time span, does not require the steps of cooling, and then reheating for fixing the metallic ring, does not require the step of machining, and other related problems mentioned herein above.
OBJECTS OF THE INVENTION
[00010] Some of the objects of the presently disclose invention, of which at the minimum one object is fulfilled by at least one embodiment disclosed herein, are as follows:
[00011] An object of the present invention is to provide an alternative, which overcomes at least one drawback encountered in the existing prior art.
[00012] Another object of the present invention is to provide a plastic moulded pipe which is sturdy, especially at ends, does not collapse when clamps are secured to ends thereof and/or crack.
[00013] Still another object of the present invention is to provide a method for manufacturing a plastic moulded pipe using a blow moulding process, wherein the method eliminates need for insertion of a metallic ring at the end of the metallic pipe.
[00014] Yet another object of the present invention is to provide a method for manufacturing a plastic moulded pipe using a blow moulding process, wherein the method is economic, has reduced time span, does not require the steps of cooling, and then reheating for fixing the metallic ring, does not require the step of machining, and other related problems mentioned herein above
[00015] Other objects and benefits of the present invention will be more apparent from the following description, which is not intended to bind the scope of the present invention.
SUMMARY OF THE INVENTION
[00016] A method for manufacturing blow moulded pipe is disclosed, wherein the blow moulded pipe obtained is having high strength, is economical and easy to manufacture.
[00017] The method for manufacturing a blow moulded comprising the step of providing a splitable mould comprising cavities for moulding the blow moulded pipe, the mould being maintained at a temperature, disposing a strengthening member within the mould, operatively disposing a parison tube within the mould, applying a stress force to the parison tube, operatively inserting a blow pin into the parison tube, conjoining the cavities thereby closing the mould and enclosing the parison tube therein, blowing a pressurized fluid into the parison tube through the blow pin, thereby inflating the parison tube such that the walls of the parison tube flush against an inner surface of the mould and that of the strengthening member and that the shape of the inflated parison tube conforms to the shape of the mould and that of the strengthening member, wherein a portion of the wall of the inflated parison tube engages with the strengthening member, maintaining the pressurized fluid within the inflated parison tube for a time period, pumping out the pressurized fluid from within the inflated parison tube, releasing the mould by decoupling the cavities to obtain an inflated parison tube comprising the blow moulded pipe having the strengthening member infused within a portion of the wall of the moulded pipe, and removing unwanted portions of the inflated parison tube comprising the blow moulded pipe.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
[00018] The present invention will now be described with the help of the accompanying drawing, in which:
[00019] FIG. 1 illustrates a schematic drawing of a plastic strengthening member of a moulded pipe in accordance with an embodiment of the present invention;
[00020] FIG. 2 illustrates a schematic drawing of a mould with the plastic strengthening member of FIG. 1 disposed therein at and around an end of the moulded pipe in accordance with the embodiments of the present invention;
[00021] FIG. 3 illustrates a schematic drawing of a moulded pipe with a strengthening member configured at and around an end thereof in accordance with the embodiments of the present invention;
[00022] FIG. 4 illustrates a schematic drawing of the moulded pipe with a strengthening member configured at and around an end thereof in accordance with the embodiments of the present invention, wherein the balloons at end thereof are removed;
[00023] FIG. 5 illustrates a schematic drawing of a cut section of the moulded pipe with the strengthening member of FIG. 4; and
[00024] FIG. 6 illustrates a flow chart of a method for manufacturing a blow moulded pipe with a plastic strengthening members embedded or infused therein at and around an end thereof in accordance with the embodiments of the present invention.
[00025] In the accompanying drawing, an underlined number is employed to represent an item over which the underlined number is positioned or an item to which the underlined number is adjacent. A non-underlined number relates to an item identified by a line linking the non-underlined number to the item.
LIST OF NUMERALS
100 – Method for manufacturing the blow moulded pipe
200 – Blow moulded pipe
200a – Balloon
202 – Splitable mould
202c – Cavities
204 – Strengthening member
204a – Semi-circular strip
204b – Tabs
204c – Neck
DETAILED DESCRIPTION
[00026] All technical terms and scientific expressions used in the present invention have the same meaning as understood by a person skilled in the art to which the present invention belongs, unless and otherwise specified.
[00027] As used in the present specification and the claims, the singular forms “a,” “an” and “the” include plural references unless the context clearly dictates otherwise.
[00028] The term "comprising” as used in the present specification will be understood to mean that the list following is non-exhaustive and may or may not include any other extra suitable things, for instance one or more additional feature(s), part(s), component(s), process step(s), sub-step(s), and /or constituent(s) as applicable.
[00029] Further, the terms “about” and “approximately" used in combination with ranges of sizes of parts, particles, compositions of mixtures, and/or any other physical properties or characteristics, are meant to include small variations that may occur in the upper and/or lower limits of the ranges.
[00030] To overcome one or more disadvantages of the prior art, the present invention provides a suitable alternative method for manufacturing of the plastic pipe using blow moulding process.
[00031] The present invention relates to a method (100) for manufacturing a blow moulded pipe (200). The method (100) is described with reference to the FIG. 6, wherein FIG. 6 illustrates a flow chart of the method (100) for manufacturing a blow moulded pipe with a plastic strengthening members embedded or infused therein at and around an end thereof in accordance with the embodiments of the present invention
[00032] In step one (102), a splitable mould (202) comprising cavities (202c) for moulding the blow moulded pipe (200) is provided, the mould (202) being maintained at a temperature. The mould (202) may be a conventional mould (202) known in the art.
[00033] In accordance with one embodiment of the present invention the mould (202) may be configured to receive an insert or a strengthening member (204) which is described herein below. The mould (202) may include grooves or ditches (not shown in the figure) to receive the strengthening member (204).
[00034] In accordance with one embodiment of the present invention the mould (202) is splitable mould (202) and can be split into two or more parts or components for ease of operations. In accordance with one embodiment of the present invention, the mould (202) comprises two cavities (202c) and which are splitable longitudinally.
[00035] In accordance with one embodiment of the present invention, the mould (202) is made of a material selected from the group consisting of metal, alloy, non-metal, and a combination thereof. Any other material which may be capable of withstanding high pressure and temperature without deforming may also be used for the construction of the mould and the present invention is not limited to the above-mentioned materials.
[00036] In accordance with one embodiment of the present invention, the metal is one selected from the group consisting of iron, steel, aluminium, and combinations thereof. Further, the metal may be any other metal other than mentioned herein above.
[00037] In the second step (104) the strengthening member (204) is disposed within the mould (202). The strengthening member (204) may be disposed at ends of the mould (202) or at any other suitable position. More specifically, the strengthening member (204) is disposed at ends of the mould such that the strengthening member (204) integrates or gets embedded with the pipe being moulded thereby providing strength to the ends of the pipe. It is to be noted that the strengthening member (204) may be disposed at any other location other than ends of the mould. The number strengthening members (204) may be in the range of 2 to 50. For example, the strengthening member (204) may have a semi-circular shape which conforms to the shape of the mould cavities, and that of the pipe being moulded. In such case, the number of strengthening members (204) may be two. The strengthening member (204) may be received in the ditch or groove configured on the inner surface of the mould. In one embodiment, a suitable glue may be used to fix the strengthening member (204) to the mould. In another embodiment the strengthening member (204) may be just disposed on the inner surface of the mould. Any other method of fixing and/or disposing the strengthening member (204) is well within the ambit of the present invention and the present invention is not limited to the above-mentioned fixing methods.
[00038] In accordance with one embodiment of the present invention, the strengthening member (204) comprises a semi-circular strip (204a); and a plurality of tabs (204b) extending from an inner surface of the semi-circular strip (204a) and a neck (204c) extending and connecting each of the semi-circular step (204a) and tabs (204b), wherein the tabs (204b) being configured to infuse with the walls of the inflated parison tube.
[00039] In accordance with one embodiment of the present invention, the strengthening member (204) may be made of one material selected from the group consisting of polyethylene, polystyrene, polyvinyl chloride, polypropylene, polyethylene terephthalate, high density polyethylene, low density polyethylene, polyurethane, fiber reinforced plastics, natural fiber reinforced plastic composite, carbon fiber reinforced plastic, metal, non-metal, alloy, and combinations thereof. In accordance with one embodiment of the present invention, the strengthening member (204) may be made of same material as that of the blow moulded pipe. In accordance with another embodiment of the present invention, the strengthening member (204) may be made of different material than that of the blow moulded pipe.
[00040] Once the insert or the strengthening member (204) is placed in position, as described herein above, in the third step (106) a parison tube at a predetermined temperature is operatively disposed within the mould (202). The parison tube (106) is conventionally known in the art and may be used herein without any further changes thereto.
[00041] In the next step, which is step four (108) a suitable stress force to is applied to the parison tube to stretch the parison tube. This is followed by insertion of a blow pin into the parison tube, which constitutes the step five (110). The blow pin facilitates injection of a pressurized fluid therethrough into the parison tube. The blow pin may include a valve to prevent back movement of the pressurized fluid out of the parison tube.
[00042] In step six (112), the cavities (202c) are joined thereby closing the mould (202) and enclosing the parison tube therein. The operation of closing the cavities may be achieved manually or may be automated. For example, the cavities may be closed by using pneumatic or hydraulics.
[00043] In step seven (114), the pressurized fluid is injected or blown into the parison tube through the blow pin, thereby inflating the parison tube such that the walls of the parison tube flush against an inner surface of the mould (202) and that of the strengthening member (204) and that the shape of the inflated parison tube conforms to the shape of the mould (202) and that of the strengthening member (204), wherein a portion of the wall of the inflated parison tube engages with the strengthening member (204). The pressure of the fluid is determined based on several factors such as wall thickness of the parison tube, the cavities, temperature of the mould etc.
[00044] In step eight (116), the pressurized fluid is maintained within the inflated parison tube for a predetermined time period. This facilitates in proper shaping of the parison tube so that the parison tube conforms to the shape of the mould and further the material of the parison tube which is in softened form solidifies and takes the shape of the pipe to be moulded.
[00045] In step nine (118) the pressurized fluid is released or pumped out from within the inflated parison tube by opening the valve in the blow pin.
[00046] In step ten (120), the mould (202) is released by decoupling the cavities (202c) to obtain an inflated parison tube comprising the blow moulded pipe (200) having the strengthening member (204) infused within a portion of the wall of the moulded pipe (200).
[00047] In step eleven (122), unwanted portions of the inflated parison tube comprising the blow moulded pipe (200) are cut and removed.
[00048] In accordance with one embodiment of the present invention, the blow moulded pipe (200) is made of one material selected from the group consisting of polyethylene, polystyrene, polyvinyl chloride, polypropylene, polyethylene terephthalate, high density polyethylene, low density polyethylene, polyurethane, fiber reinforced plastics, natural fiber reinforced plastic composite, carbon fiber reinforced plastic, and combinations thereof.
[00049] In accordance with one embodiment of the present invention, the temperature of the mould (202) is in the range of 20 ?C to 35 ?C.
[00050] In accordance with one embodiment of the present invention, the temperature of the pressurized fluid is in the range of 20 ?C to 35 ?C.
[00051] In accordance with one embodiment of the present invention, the temperature of the parison is in the range of 120 ?C to 320 ?C.
[00052] In accordance with one embodiment of the present invention, the mould (202) being cooled by a cooling fluid, wherein the temperature of the cooling fluid being in the range of 10 ?C to 20 ?C.
[00053] In accordance with one embodiment of the present invention, the pressure of the pressurized fluid is in the range of 1 bar to 10 bar.
[00054] In accordance with one embodiment of the present invention, the blow moulded pipe may have a diameter in the range of 20 mm to 300 mm, a wall thickness in the range of 1 mm to 10 mm, and an ovality of less than 10 mm.
[00055] In accordance with one embodiment of the present invention, the semi-circular strip (204a) may have a wall thickness in the range of 1 mm to 10 mm, a radius of curvature in the range of 20 mm to 300 mm, and a width in the range of 1 mm to 50 mm.
[00056] In accordance with one embodiment of the present invention, the tabs (204b) may have a number in the range of 1 to 150, a height in the range of 1 mm to 25 mm, a wall thickness in the range of 1 mm to 10 mm, a perimeter in the range of 1 mm to 50 mm, a width in the range of 1 mm to 50 mm;
[00057] In accordance with one embodiment of the present invention, the neck portion (204c) may have a number in the range of 1 to 10, a height in the range of 1 mm to 25 mm, a wall thickness in the range of 1 mm to 10 mm and a width in the range of 1 mm to 50 mm.
[00058] In accordance with one embodiment of the present invention, the tabs (204b) being arranged in one or more row along the inner surface of the strengthening member (204).
[00059] In accordance with one embodiment of the present invention, the pressurized fluid is air, nitrogen, and combinations thereof.
[00060] In accordance with one embodiment of the present invention, the pressurized fluid has a temperature in the range of 20 ?C to 35 ?C.
[00061] In accordance with one embodiment of the present invention, the pressurized fluid has a pressure is in the range of 1 bar to 15 bar.
[00062] In accordance with one embodiment of the present invention, the pressurized fluid is maintained in the parison for a time period in the range of 1 second to 300 seconds.
[00063] In accordance with one embodiment of the present invention, a ratio of wall thickness of the blow moulded pipe to the wall thickness of the semi-circular strip is in the range of 0.02 to 50.
[00064] In accordance with one embodiment of the present invention, a ratio of wall thickness of the blow moulded pipe to the wall thickness of the neck portion is in the range of 0.02 to 50.
[00065] In accordance with one embodiment of the present invention, the step of removing the unwanted portions of the inflated parison tube includes the step of cutting a balloon (200a) formed at ends of the inflated parison tube during the step of blow molding and cutting non-essential portions.
[00066] In accordance with one embodiment of the present invention, the blow moulded pipe (200) is having a crush strength in the range of 1 MPa to 50 Mpa, an ovality in the range of 0.1 mm to 10 mm when a torque in the range of 2.5 to 10 Nm is applied and is capable of sustaining leakages at low pressure in the of 0.1 to 0.9 bar.
[00067] In accordance with one embodiment of the present invention, the method (100) eliminates the step of metal ring fitting, eliminates the step of reheating the blow moulded pipe (200) for metal ring fitting, eliminates the step of machining the blow moulded pipe (200) for metal ring fitting, eliminates cracking the blow moulded pipe (200) during the step of metal ring fitting, eliminates the step of cooling the blow moulded pipe (200), reduces the cost of manufacturing the blow moulded pipe (200) by a factor of 5 % to 10 %, and reduces time required for metal ring fitting, cooling, machining, and reheating; the time being reduced from 10 minutes to 100 minutes.
Examples
[00068] The present invention is now described with reference to the following examples which are provided for better understanding of the invention and not for limiting the scope thereof.
Example 1 (In accordance with the embodiments of the present invention).
[00069] A blow moulded pipe having a diameter of 100 mm, a wall thickness of 5 mm, and ovality of 5 mm was manufactured employing the method described herein above (not repeated for sake of brevity). The blow moulded pipe was made of polyethylene material. The strengthening member was embedded during the moulding step in accordance with the embodiments of the present invention. Two strengthening members were incorporated at two ends of the pipe. The dimensions of the strengthening members and components thereof are tabulated in table 1 herein below along with the essential parameters and quality parameters.
Table 1A
Blow moulded pipe
Material Wall thickness (mm) Diameter (mm) Ovality (mm)
1 Polyethylene 5 100 5
Table 1B
Strengthening member
Material W R N n HT TT Tp Tw Tr
2 Polyethylene 5 50 2 5 3 5 314 10 1
W – wall thickness (mm)
R - Radius of curvature (mm)
N - Number of strengthening members
n – number of tabs
HT – Tab height
TT – Tab thickness
Tp – Tab perimeter
Tw – Tab width
Tr – Tab rows
Table 1C
Sr. No. Parameter Value
1 Parison temperature 175 ?C
2 Mould temperature 30 ?C
3 Fluid pressure 6 bar
4 Chiller temperature 20 ?C
Example 2 : Blow moulded pipe made in accordance with the conventional method
[00070] A blow moulded pipe was moulded in accordance with the conventional method wherein no insert or strengthening member was embedded into the mould during the step of blow moulding. The blow moulded pipe was then fitted with a metal ring each at ends thereof. For fitting the metal ring, the ends thereof had to be cut and bored with increased the manufacturing time. Further, on fitting the metal rings, the pipe had to be heated and cooled, which further increased the number of steps and processing time and also the cost.
[00071] On comparing the two examples, it is observed that the method of the present invention is time and cost efficient as it eliminates few steps which are essential in the conventional method.
TECHNICAL ADVANCES AND ECONOMICAL SIGNIFICANCE OF THE PRESENT INVENTION
[00072] The present invention provides a method for manufacturing a blow moulded pipe made of plastic material, and the blow moulded pipe obtained therefrom.
[00073] The method of the present invention has several advantages over the known prior art methods, which include, but are not limited to,
- The method of the present invention is simple, economical, and time efficient;
- The method of the present invention eliminates the need for use of metallic ring as reinforcement in the blow moulded plastic pipe;
- The method of the present invention reduces the cost of manufacturing the blow moulded pipe by a factor of 5 % to 10 % as compared to the conventional methods;
- The method of the present invention eliminates the need for reheating, machining, cutting and the issues of mismatch of the metal ring size and the pipe size, and lose fitting of the metal ring.
[00074] The blow moulded pipe of the present invention is sturdy, have high strength, does not collapse and/or crack during fitment of clamps to ends thereof, have good dimensional stability, reduced ovality, etc.
,CLAIMS:We claim:
1. A method (100) for manufacturing a blow moulded pipe (200), the method (100) characterized by having the following steps:
- providing a splitable mould (202) comprising cavities (202c) for moulding the blow moulded pipe (200), the mould (202) being maintained at a temperature (102);
- disposing a strengthening member (204) within the mould (202)(104);
- operatively disposing a parison tube within the mould (202)(106);
- applying a stress force to the parison tube(108);
- operatively inserting a blow pin into the parison tube(110);
- conjoining the cavities (202c) thereby closing the mould (202) and enclosing the parison tube therein (112);
- blowing a pressurized fluid into the parison tube through the blow pin, thereby inflating the parison tube such that the walls of the parison tube flush against an inner surface of the mould (202) and that of the strengthening member (204) and that the shape of the inflated parison tube conforms to the shape of the mould (202) and that of the strengthening member (204), wherein a portion of the wall of the inflated parison tube engages with the strengthening member (204)(114);
- maintaining the pressurized fluid within the inflated parison tube for a time period (116);
- pumping out the pressurized fluid from within the inflated parison tube (118);
- releasing the mould (202) by decoupling the cavities (202c) to obtain an inflated parison tube comprising the blow moulded pipe (200) having the strengthening member (204) infused within a portion of the wall of the moulded pipe (200)(120); and
- removing unwanted portions of the inflated parison tube comprising the blow moulded pipe (200)(122).
2. The method as claimed in claim 1, wherein the blow moulded pipe (200) is made of one material selected from the group consisting of polyethylene, polystyrene, polyvinyl chloride, polypropylene, polyethylene terephthalate, high density polyethylene, low density polyethylene, polyurethane, fiber reinforced plastics, natural fiber reinforced plastic composite, carbon fiber reinforced plastic, and combinations thereof.
3. The method as claimed in claim 1, wherein
- the temperature of the mould (202) is in the range of 20 ?C to 35 ?C;
- the temperature of the pressurized fluid is in the range of 20 ?C to 35 ?C;
- the temperature of the parison is in the range of 120 ?C to 320 ?C;
- the mould (202) being cooled by a cooling fluid, wherein the temperature of the cooling fluid being in the range of 10 ?C to 20 ?C; and
- the pressure of the pressurized fluid is in the range of 1 bar to 10 bar.
4. The method as claimed in claim 1, wherein the splitable mould (202)
- comprises two cavities (202c) and is splitable longitudinally;
- is made of a material selected from the group consisting of metal, alloy, non-metal, and a combination thereof; and
- the metal is one selected from the group consisting of iron, steel, aluminium, and combinations thereof.
5. The method as claimed in claim 1, wherein
- the blow moulded pipe having:
o a diameter in the range of 20 mm to 300 mm;
o a wall thickness in the range of 1 mm to 10 mm; and
o an ovality of less than 10 mm;
6. The method as claimed in claim 1, wherein
- the strengthening member (204) comprising
o a semi-circular strip (204a); and
o tabs (204b) extending from an inner surface of the semi-circular strip (204a);
o a neck (204c) extending and connecting each of the semi-circular step (204a) and tabs (204b);
wherein the tabs (204b) being configured to infuse with the walls of the inflated parison tube;
wherein the strengthening member (204) is made of one material selected from the group consisting of polyethylene, polystyrene, polyvinyl chloride, polypropylene, polyethylene terephthalate, high density polyethylene, low density polyethylene, polyurethane, fiber reinforced plastics, natural fiber reinforced plastic composite, carbon fiber reinforced plastic, metal, non-metal, alloy, and combinations thereof;
- the strengthening member (204) having a number in the range of 2 to 5;
- the semi-circular strip (204a) having:
o a wall thickness in the range of 1 mm to 10 mm;
o a radius of curvature in the range of 20 mm to 300 mm; and
o a width in the range of 1 mm to 50 mm;
- the tabs (204b) having:
o a number in the range of 1 to 150;
o a height in the range of 1 mm to 25 mm;
o a wall thickness in the range of 1 mm to 10 mm;
o a perimeter in the range of 1 mm to 50 mm;
o a width in the range of 1 mm to 50 mm;
- the neck portion (204c) having:
o a number in the range of 1 to 10;
o a height in the range of 1 mm to 25 mm;
o a wall thickness in the range of 1 mm to 10 mm;
o a width in the range of 1 mm to 50 mm;
- the tabs (204b) being arranged in one or more row along the inner surface of the strengthening member (204).
7. The method as claimed in claim 1, wherein the pressurized fluid:
- is air, nitrogen, and combinations thereof;
- has a temperature in the range of 20 ?C to 35 ?C;
- a pressure is in the range of 1 bar to 15 bar; and
- is maintained in the parison for a time period in the range of 1 second to 300 seconds.
8. The method as claimed in claim 1, wherein
- a ratio of wall thickness of the blow moulded pipe to the wall thickness of the semi-circular strip is in the range of 0.02 to 50; and
- a ratio of wall thickness of the blow moulded pipe to the wall thickness of the neck portion is in the range of 0.02 to 50.
9. The method as claimed in claim 1, wherein the step of removing the unwanted portions of the inflated parison tube includes the step of cutting a balloon formed at ends of the inflated parison tube during the step of blow molding and cutting non-essential portions.
10. The method (100) as claimed in claim 1, wherein
- the blow moulded pipe (200):
o having a crush strength in the range of 1 MPa to 50 Mpa;
o having an ovality in the range of 0.1 mm to 10 mm when a torque in the range of 2.5 to 10 Nm is applied; and
o sustains leakages at low pressure in the of 0.1 to 0.9 bar;
- the method (100):
o eliminates the step of metal ring fitting;
o eliminates the step of reheating the blow moulded pipe (200) for metal ring fitting;
o eliminates the step of machining the blow moulded pipe (200) for metal ring fitting;
o eliminates cracking the blow moulded pipe (200) during the step of metal ring fitting;
o eliminates the step of cooling the blow moulded pipe (200);
o reduces the cost of manufacturing the blow moulded pipe (200) by a factor of 5 % to 10 %; and
o reduces time required for metal ring fitting, cooling, machining, and reheating; the time being reduced from 10 minutes to 100 minutes.
Dated this 06th day of October 2021
For the Applicant

Deepak Pradeep Thakur
The Applicant’s Patent Agent
IN/PA – 3687
To,
The Controller of Patents
The Patent Office,
At Mumbai