FORM 2
THE PATENT ACT 1970
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. TITLE OF THE INVENTION:
"Composite Pressure Vessel and Manufacturing Process Thereof
2. APPLICANT
(a) NAME: Autodynamic Engineering Private Limited
(b) NATIONALITY: Indian Company Registered Under the Companies
Act 1956
(c) ADDRESS: H - 402, Pinnae Kanchanganga, D. P. Road, Aundh
Pune-411007 Maharashtra, India
3. PRREAMBLE TO THE DESCRIPTION
COMPLETE
The following specification particularly describes the invention and the manner in which it is to be performed.

Composite Pressure Vessel and Manufacturing Process Thereof
Field of the invention
The present invention relates to composite pressure vessel and manufacturing process for producing the same.
Background of the invention
Existing Pressure Vessels are primarily divided into types:
Type 1 = Pressure Vessels entirely fabricated in Steel (Very High Weight) Type 2 = Pressure vessels primarily with a steel structure and Filament
wound body (Lower Weight & Increase in Cost) Type 3 = Aluminum Liner with Carbon Fiber Winding (Lower Weight
than Type 2 but much higher cost) Type 4 = Blow Molded Liner with Filament Winding usually Carbon Fiber
(Lowest Weight amongst all cylinders but highest Costs)
In case of Composite pressure vessels of nature mentioned above, liner is manufactured by blow molding of high density polyethylene and the reinforcement fiber used is carbon fiber. This makes the pressure vessels lighter than the metal pressure vessel and is much appreciated for the weight reduction of pressure vessel. However to replace the metal pressure vessel to composite pressure vessel by above art is not advantageous due to high cost of raw material and eventually having a very high cost of the product for final user.The present invention is directed to solving the above problem of costs and achieves the target of weight reduction and to make composite pressure vessel viable for commercial application.

Object of the invention
Object of the present invention is to provide a composite pressure vessel and manufacturing process thereof, which is capable of reducing weight by replacing the metal pressure vessel by nonmetallic composite pressure vessel, as well as to achieve the cost target.
Another object of the present invention is to provide a composite pressure vessel and manufacturing process thereof, wherein a pressure vessel is designed with outer shell, manufactured of composite material of impregnated glass / basalt /carbon / Thermo plastic fibers or combination thereof with thermoplastic/thermosetting resin, which has good resistance to permeability and insures joint is leak proof.
Yet another object of the present invention is to provide a composite pressure vessel and manufacturing process thereof, which has reinforcement of laminate.
Summary of the invention
According to the present invention there is provided a composite pressure vessel for holding pressurized fluid, the vessel comprising:
a body of laminate for providing outermost cover;
a liner disposed inside the body of laminate; and
a boss disposed on a side of the body of laminate for communicating with an interior portion of liner.
Typically, wherein the body of laminate is made of impregnated glass / basalt /carbon / Thermo plastic fibers or combination thereof fiber with thermosetting/thermoplastic resin.

Typically, wherein the liner having a liner upper portion and a liner lower portion, wherein the liner upper portion and a liner lower portion are joined with each other by welding / joining/ gluing / sealing/ pasting/ screwing/ coating/ laminating/ banding / sleeveing etc
Typically, wherein the boss is insert-molded in the liner.
Typically, wherein the boss is made of aluminum / copper / brass / Steels/ Other Metals / Alloys / Non - metals.
Typically, wherein the liner is made by injection molding of thermoplastic.
Typically, wherein the boss is hexagonal / slot cut in shape.
Typically, wherein the boss having a plurality of slots configured for providing better grip and leak proof structure to insert molded half of the liner, a boss neck, a boss flange, a threading for cylinder valve and hex nut.
Brief description of the drawings
Figure 1 is model of typical pressure vessel with inner part liner and glass fiber reinforced shell;
Figure 2a is the isometric view of the boss-part of the vessel;
Figure 2b is the side view of the boss;
Figure 3 is the side view of the first part of the Injection Molded liner which comes with insert molded boss;
Figure 4 is the side view of the second part of a liner of the present invention;

Figure 5a and 5b are isometric side view of a winding-cap of the present invention;
Figure 6 is isometric view of first part of liner with insert molded Boss.
Detailed Description of the invention
The foregoing objects of the invention are accomplished and the problems and shortcomings associated with prior art techniques and approaches are overcome by the present invention described in the present embodiment.
The present invention provides a composite pressure vessel and manufacturing process thereof is capable of reducing weight by replacing the metal pressure vessel by nonmetallic composite pressure vessel, as well as to achieve the cost target. Further, the composite pressure vessel has good resistance to permeability and insures joint is leak proof. Furthermore, the composite pressure vessel has reinforcement of laminate.
This present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in bracket in the following description.
Referring now to figure 1, a pressure vessel (100) for holding pressurized fluid therein in accordance with the present invention is illustrated. The vessel (100) includes a body of laminate (2), a liner (3), and a boss (4) (refer figure 2a & 2b). The body of laminate (2) is made of impregnated glass fiber with thermosetting/thermoplastic resin. The liner (3) includes a liner upper portion (9) and a liner lower portion (11) which are joined together with each other by welding /joining/ gluing / sealing/ pasting/ screwing/ coating/ laminating/ banding

/ sleeveing. The boss (4) (refer figure 2a,2b & 6) is provided at an end portion of the vessel (100) to provide port communicating with an interior of the vessel (100) thereof.
Referring now to figures 2a & 2b, various views of the boss (4) in accordance with the present invention. The boss (4) is insert-molded in the liner upper portion (9) of the liner (3). In an embodiment, the boss (4) is made of metal / non metal. The boss (4) includes a plurality of slots (5), a boss neck (8), a boss flange (6), a threading for cylinder valve (18) and a hex nut (7). The plurality of slots (5) configured on the boss (4) for providing better grip and leak proof structure to insert molded half of the liner (3). During injection molding process, a molten thermoplastic material is injected to takes a shape of the boss part (4) and get integrated with liner (9) thereby forming rigid bonded portion (10) refer figure 3. The hexagonal shape (7) of the boss (4) is to aid the fitment of valve part of the vessel (100).
Edges (16) and (17) of the vessel (100) (as shown in figures 3 and 4) are connected together to form a leak proof strong joint to form the hollow liner (3) of the present invention. The liner (3) is made of thermoplastic material. The boss (4) is made of metal / non metal. An extended portion (12) of the lower liner (11) is provided to fit in to undercut portion (15) (refer figure 6) of a winding cap (13) (refer fig 5). The winding cap (13) aids to mount and provide support to the liner (3) during winding process. The winding cap (13) is made up of thermoplastic or metal material.
The vessel (100) of the present invention enables to manufacture cost effective Composite Pressure Vessels wherein the process of using Injection Molded Polymer Liner with Built in Boss Part and filament winding. So that potential product cost of the vessel can be minimized.

The present invention also includes a process for manufacture the vessel (100). The liner (3) produced by using an injection molding process wherein the boss (4) is inserted during the injection molding process of the liner (3). The material used for the liner (3) is either Polyamide or HDPE. The design of the Boss (4) is such that it forms an integral part of the liner (3) during the injection molding process. This integration is achieved by the slots (5) configured on the boss (4), which allows the plastic material to flow in between the slots (5). The insert molding of the boss (5) helps to achieve the following advantages:
a. The joint provides better sealing between the Boss (4) and the Liner
(3).
b. Jt reduces costs as no additional operations need to be done for
fixing of the boss (4).
c. It forms a robust joint for mounting of valves to the pressure vessel.
Further, the two injection molded parts of the liner upper liner (9) and the lower liner (11) are then joined together to form the liner (3) wherein this joining / gluing / sealing/ pasting/ screwing/ coating/ laminating/ banding / sleeveing can be done by any of the following process:
a) Using the Patented Hot Gas Welding Technology.
b) Vibration Welding
c) Hot Plate Welding
d) Spin Welding
e) Gluing
0 IR Welding
During process flash or extra unwanted material is removed from welded cylinder. The joint is then leak tested by using air/hydro pressure. Once liner (3) passes the leak test it goes for the filament winding to form laminate part of the vessel (100). The advantage of using Glass Fiber over Carbon Fiber is that it reduces the overall cost of the cylinder up to 60% as compared to conventional composite pressure vessels. Though there is an increase in the weight over the conventional carbon

Fiber composite Type 3 & Type 4 Cylinder / pressure vessels , there is a weight saving up to 50% over Type 1 Steel cylinder & Type 2 Steel Composite Cylinder having similar capacity.
Further, the laminate winding is done using either of the two processes:
a. Robotic Arm Winding
b. Conventional Gantry Type Filament Winding Machine.
The vessels (100) are then cured in an oven to complete the lamination process. The vessels (100) are finally finished with a lacquer coating. The vessels (100) are then tested as per the different test specifications prevalent in the different markets.
Detailed descriptions of the preferred embodiments are provided herein; however, it is to be understood that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in art to employ the present invention in virtually any appropriately detailed system, structure, or matter.
The embodiments of the invention as described above and the methods disclosed herein will suggest further modification and alterations to those skilled in the art. Such further modifications and alterations may be made without departing from the spirit and scope of the invention.

We Claim:
1. A composite pressure vessel for holding pressurized fluid, the vessel
comprising:
a body of laminate for providing outermost cover; a liner disposed inside the body of laminate; and a boss insert-molded in the liner and disposed on a side of the body of laminate for communicating with an interior portion of the liner.
2. The composite pressure vessel as claimed in claim 1, wherein the body of laminate is made of impregnated glass/ basalt /carbon / Thermo plastic fibers or combination thereof with thermosetting/thermoplastic resin.
3. The composite pressure vessel as claimed in claim 1, wherein the liner having a liner upper portion and a liner tower portion, wherein the liner upper portion and a liner lower portion are secured with each other by welding /joining/ gluing / sealing/ pasting/ screwing/ coating/ laminating/ banding / sleeveing
4. The composite pressure vessel as claimed in claim 1, wherein the boss is made of aluminum / metal / non-metal.
5. The composite pressure vessel as claimed in claim 1, wherein the liner is made by injection molding of thermoplastic.
6. The composite pressure vessel as claimed in claim 1, wherein the boss is hexagonal / slot cut in shape.

7, The composite pressure vessel as claimed in claim 1, wherein the boss having a plurality of slots configured for providing better grip and leak proof structure to insert molded half of the liner, a boss neck, a boss flange, a threading for cylinder valve and hex nut.