Split valve seat plastic liner composite pressure vessel and manufacturing method thereof

Abstract

The present invention discloses a split valve seat plastic liner composite pressure vessel and a manufacturing method thereof, and belongs to the technical field of storage and transportation pressure vessels. The pressure vessel comprises a plastic liner, a split valve seat installed on the plastic liner, and a fiber reinforcement layer wrapped around the outer surface of the plastic liner and the split valve seat. The split valve seat comprises a pre-tightening valve seat and a supporting valve seat. The flange portion of the pre-tightening valve seat is arranged inside the plastic liner, and the external thread portion of the pre-tightening valve seat extends from the hole at the end of the plastic liner. The supporting valve seat is arranged outside the plastic liner and is connected to the pre-tightening valve seat through the external thread portion. The present invention places the pre-tightening valve seat inside the storage and transportation container through the split valve seat design, and pre-tightens the plastic liner of the storage and transportation container through the connection with the supporting valve seat, thereby constraining the relative displacement between the plastic liner and the metal valve seat, and effectively improving the strength and fatigue life of the interface between the plastic liner and the metal valve seat.

Description

Technical Field

[0001] The invention belongs to the technical field of storage and transportation pressure vessels, and in particular relates to a split valve seat plastic liner composite material pressure vessel and a manufacturing method thereof. Background Art

[0002] In recent years, hydrogen production and storage equipment has made great progress. Compressed hydrogen generally uses plastic as the plastic liner, and several layers of carbon fiber are wrapped around its outer surface, making it not only strong but also lightweight.

[0003] Storage and transportation containers need to be equipped with valve seats and external connections for gas delivery. In order to meet the effective connection between the external valve, the end of the plastic liner needs to be designed with a metal valve seat to meet the structural integrity under loads such as high sealing preload force and axial tension. However, the connection between the existing metal valve seat and the end of the plastic liner is too dependent on the development of interface adhesive materials, and the adhesive has always been unable to effectively meet the requirements of interface strength and interface fatigue life caused by complex deformation of the valve seat caused by temperature and pressure changes. Summary of the invention

[0004] In order to solve the above technical problems, the present invention proposes a split valve seat plastic liner composite pressure vessel, which has high reliability, simple structure and convenient installation.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a split valve seat and plastic liner composite pressure vessel, comprising a plastic liner, a split valve seat installed on the plastic liner, and a fiber reinforced layer wrapped around the plastic liner and the outer surface of the split valve seat, the split valve seat comprising a pre-tightening valve seat and a supporting valve seat, the flange portion of the pre-tightening valve seat being arranged inside the plastic liner, the pre-tightening valve seat also being provided with an external threaded portion, the supporting valve seat being arranged outside the plastic liner and fixedly connected to the external threaded portion of the pre-tightening valve seat by threads.

[0006] Furthermore, a concave portion, an arc surface portion and a column surface portion which are connected in sequence are provided at a connection point between the plastic liner and the split valve seat.

[0007] Furthermore, the supporting valve seat has a flange portion adapted to the recessed portion of the plastic liner, and the outer arc surface of the flange portion is smoothly transitionally connected to the arc surface portion.

[0008] Furthermore, the preload valve seat and / or the support valve seat are made of aluminum alloy, titanium alloy, stainless steel, carbon steel or plastic through a machining process.

[0009] Furthermore, the fiber reinforcement layer is a solidified mixture of carbon fiber, glass fiber or Kevlar fiber and resin.

[0010] Furthermore, an adhesive is provided between the plastic liner and the preload valve seat and the support valve seat.

[0011] Furthermore, a sealing filler is provided between the external threaded portion of the pre-tightening valve seat and the supporting valve seat.

[0012] Furthermore, the thread of the external threaded portion is a tapered pipe thread, the taper of the tapered pipe thread is 1:16, and the tooth angle of the tapered pipe thread is 55° or 66°.

[0013] Furthermore, the thread of the external thread portion is a left-hand thread.

[0014] A method for manufacturing a split valve seat plastic liner composite pressure vessel comprises the following steps:

[0015] S1: applying adhesive to the outer surface of the concave portion of the plastic liner and the flange portion of the supporting valve seat respectively, positioning the outer surface of the plastic liner and the flange portion of the supporting valve seat and applying a pressing force until the adhesive is completely cured;

[0016] S2: Adhesive is applied to the inner surface of the concave part of the plastic liner and the flange part of the pre-tightening valve seat respectively, the pre-tightening valve seat is rotated to connect the external thread part of the pre-tightening valve seat with the supporting valve seat, and a pre-tightening force is applied to make the contact surfaces between the pre-tightening valve seat and the plastic liner contact each other, and the adhesive on the contact surface is solidified, and a press fit is achieved between the pre-tightening valve seat and the plastic liner under the action of the pre-tightening force;

[0017] S3: welding the end cap of the plastic liner to the cylinder of the plastic liner;

[0018] S4: coating the outer surface of the container formed by the plastic liner and the split valve seat with a transition agent, and winding a fiber reinforcement layer on the outer surface of the container;

[0019] S5: placing the wound container in an oven and rotating and curing under pressure, and finally preparing a split valve seat fiber fully wound composite pressure vessel.

[0020] Beneficial technical effects of the present invention:

[0021] From the perspective of structural innovation, the present invention adopts a split valve seat design to place the pre-tightened valve seat inside the storage and transportation container, and locks the plastic liner of the storage and transportation container through the connection with the supporting valve seat, thereby constraining the relative displacement between the plastic liner and the metal valve seat, effectively improving the interface strength and fatigue life between the plastic liner and the metal valve seat.

[0022] The split valve seat of the present invention has the advantages of simple structure, convenient installation, etc., which greatly improves the production efficiency of lightweight high-pressure pressure vessels and reduces production costs.

[0023] The invention also discloses a method for manufacturing a split valve seat plastic liner composite material pressure vessel, which has simple procedures and high yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solution of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0025] Figure 1 It is a schematic diagram of the overall structure of the split valve seat plastic liner composite pressure vessel of the present invention;

[0026] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0027] Figure 3 It is a schematic diagram of the structure of the plastic liner of the present invention;

[0028] Figure 4 This is a schematic diagram of the pre-tightening valve seat structure of the present invention;

[0029] Figure 5 It is a structural schematic diagram of the support valve seat of the present invention;

[0030] Figure 6 It is a schematic diagram of the sealing structure of the present invention;

[0031] Figure 7 It is a schematic diagram of the connection between the present invention and an external valve.

[0032] Among them, 1-plastic liner, 11-recessed part, 12-arc part, 13-column part, 14-support part, 2-fiber reinforced layer, 3-pre-tightened valve seat, 31-flange part, 32-external thread part, 33-internal thread part, 4-support valve seat, 41-flange part, 42-extending part, 5-adhesive, 6-sealing packing, 7-external valve, 8-sealing ring. DETAILED DESCRIPTION

[0033] The present invention will now be further described in conjunction with the accompanying drawings. These drawings are simplified schematic diagrams that only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0034] like Figure 1 and Figure 2As shown, a split valve seat and plastic liner composite pressure vessel includes a plastic liner 1, a split valve seat installed on the plastic liner 1, and a fiber reinforced layer 2 wrapped around the plastic liner 1 and the outer surface of the split valve seat. The split valve seat includes a pre-tightening valve seat 3 and a supporting valve seat 4. The flange portion 31 of the pre-tightening valve seat 3 is arranged inside the plastic liner 1, and the external threaded portion 32 of the pre-tightening valve seat 3 extends out from the hole of the plastic liner 1. The supporting valve seat 4 is arranged outside the plastic liner 1 and is fixedly connected to the external threaded portion 32 of the pre-tightening valve seat 3 through its own internal thread. The pre-tightening valve seat 3 and the supporting valve seat 4 clamp the cylinder wall of the plastic liner 1 and apply a certain pre-tightening force to improve the sealing effect between the plastic liner 1 and the split valve seat. Figure 4 and Figure 5 As shown, the flange portion 31 and the flange portion 41 both play a role of limiting, and the two sandwich the plastic liner 1 and the cylinder wall in the middle, making the structure of the split valve seat stronger. In addition, the fiber reinforcement layer 2 wraps the plastic liner 1 and the split valve seat inside, which can limit the plastic liner 1 and the split valve seat from opening outward, providing a greater restraining force.

[0035] Preferably, the thread at the external thread portion 32 is a conical pipe thread, which has better sealing performance. More preferably, the taper of the conical pipe thread is 1:16, and the tooth angle of the conical pipe thread is 55° or 66°.

[0036] In addition, the thread at the external thread portion 32 is a left-hand thread, which is also called a reverse thread. The reverse thread here plays a role in preventing loosening.

[0037] like Figure 4 As shown, in order to achieve better effects, a recess 11 is provided at the end of the plastic liner 1, and is connected in sequence with an arc surface 12 and a column surface 13. The recess 11 of the plastic liner 1 forms a plurality of folded edges, which are similar to the effect of reinforcing ribs and can effectively improve the structural strength of the recess 11. A support portion 14 is also provided at the end of the plastic liner 1, and the external threaded portion 32 of the pre-tightening valve seat 3 passes through the support portion 14, so that the contact area between the pre-tightening valve seat 3 and the plastic liner 1 is larger and the strength is better.

[0038] like Figure 5 As shown, the support valve seat 4 has a flange portion 41 and a protruding portion 42, the flange portion 41 is adapted to the recessed portion 11, and the outer surface of the flange portion 41 is smoothly connected to the arc portion 12. The smooth transition between the outer surface of the flange portion 41 and the arc portion 12 can make the entire cylinder wall smooth and flat, and the force is evenly applied.

[0039] The plastic liner 1 is preferably made of high-density polyethylene or polyamide through injection molding, rotational molding or blow molding, which can meet the requirements of lightweight pressure vessels.

[0040] In order to improve the strength of the split valve seat, improve the sealing reliability and the number of repeated uses, the preload valve seat 3 and the support valve seat 4 are preferably made of high-strength metal materials, such as aluminum alloy, titanium alloy, stainless steel, carbon steel, or high-strength plastic materials. The split valve seat is generally manufactured by machining technology, which can ensure the manufacturing accuracy and surface roughness of the split valve seat parts.

[0041] The fiber reinforced layer 2 here plays a very important role. It effectively improves the strength of the pressure vessel with a very small weight and is an effective means to achieve lightweight pressure vessels. The fiber reinforced layer 2 is made of carbon fiber or glass fiber or Kevlar fiber mixed with resin and fully wound on the plastic liner 1 and the split valve seat, and then cured.

[0042] like Figure 6 As shown, adhesive 5 is applied between the plastic liner 1 and the pre-tightening valve seat 3, and adhesive 5 is also applied between the plastic liner 1 and the supporting valve seat 4. Applying adhesive 5 can not only facilitate the installation of the pre-tightening valve seat 3, the supporting valve seat 4 and the plastic liner 1, but also achieve better sealing between the three. In addition, a sealing filler 6 is provided between the threaded connection of the pre-tightening valve seat 3 and the supporting valve seat 4, so that the threaded connection can achieve a better sealing effect.

[0043] like Figure 7 As shown, when the split valve seat plastic liner composite pressure vessel of the present invention is connected to the external valve 7, the external valve 7 is connected to the internal thread portion 33 of the pre-tightening valve seat 3, and the internal thread portion 33 can be set as a conical pipe thread or a cylindrical thread. A sealing ring 8 is set between the external valve 7 and the supporting valve seat 4 to achieve better sealing.

[0044] like Figure 1 As shown, the plastic liner 1 is usually composed of end caps at both ends and a straight tube portion in the middle. The split valve seat is usually installed on the end caps at both ends of the plastic liner 1, and the two end caps and the straight tube portion are assembled together by welding.

[0045] The present invention also discloses a method for manufacturing a split valve seat plastic liner composite material pressure vessel, the steps of which are as follows:

[0046] S1: applying adhesive to the outer surface of the concave portion 11 of the plastic liner 1 and the flange portion 41 of the supporting valve seat 4, respectively, positioning the outer surface of the plastic liner 1 and the flange portion 41 of the supporting valve seat 4 and applying a pressing force until the adhesive is completely cured;

[0047] S2: Adhesive is applied to the inner surface of the recessed portion 11 of the plastic liner 1 and the flange portion 31 of the pre-tightening valve seat 3, respectively, and the pre-tightening valve seat 3 is rotated to connect the external threaded portion 31 of the pre-tightening valve seat 3 with the supporting valve seat 4, and a pre-tightening force is applied to make the contact surfaces between the pre-tightening valve seat 3 and the plastic liner 1 contact each other, and after the adhesive on the contact surface is cured, a press fit is achieved between the pre-tightening valve seat 3 and the plastic liner 1 under the action of the pre-tightening force;

[0048] S3: welding the end portion of the plastic liner 1 to the straight tube portion of the plastic liner 1;

[0049] S4: coating the outer surface of the container formed by the plastic liner 1 and the split valve seat with a transition agent, and winding a fiber reinforcement layer on the outer surface of the container;

[0050] S5: placing the wound container in an oven and rotating and curing under pressure to finally prepare a fiber fully wound composite pressure vessel.

[0051] Preferably, the sealing portion and the straight tube portion of the plastic liner 1 are welded together by heat-melt welding, laser welding or ultrasonic welding.

[0052] The above embodiments are only descriptions of the preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary engineering and technical personnel in the field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A split valve seat plastic liner composite pressure vessel, characterized in that: It comprises a plastic liner (1), a split valve seat mounted on the plastic liner (1), and a fiber-reinforced layer (2) wound around the plastic liner (1) and the outer surface of the split valve seat, the split valve seat comprising a pre-tightening valve seat (3) and a supporting valve seat (4), the flange portion (31) of the pre-tightening valve seat (3) being arranged inside the plastic liner (1), the pre-tightening valve seat (3) also being provided with an external threaded portion (32), and the supporting valve seat (4) being arranged outside the plastic liner (1) and fixedly connected to the external threaded portion (32) of the pre-tightening valve seat (3) via threads; The connection between the plastic liner (1) and the split valve seat is provided with a recessed portion (11), an arcuate portion (12) and a cylindrical portion (13) which are connected in sequence; The supporting valve seat (4) has a flange portion (41) adapted to the recessed portion (11) of the plastic liner (1), and the outer arc surface of the flange portion (41) is smoothly transitionally connected to the arc surface portion (12); The thread of the external thread portion (32) is a conical pipe thread, the taper of the conical pipe thread is 1:16, and the tooth angle of the conical pipe thread is 55° or 66°; the thread at the external thread portion (32) is a left-hand thread; The fiber reinforcement layer (2) wraps the plastic liner (1) and the split valve seat therein, thereby limiting the plastic liner (1) and the split valve seat from opening outwards; a support portion (14) is also provided at the end of the plastic liner (1), and the external threaded portion (32) of the preloaded valve seat (3) passes through the support portion (14); The split valve seat plastic liner composite material pressure vessel is connected to an external valve (7); the external valve (7) is connected to the internal thread portion (33) of the pre-tightening valve seat (3); the internal thread portion (33) is configured as a conical pipe thread; a sealing ring (8) is provided between the external valve (7) and the supporting valve seat (4); An adhesive (5) is provided between the plastic liner (1), the preload valve seat (3) and the support valve seat (4); A sealing filler (6) is provided between the external threaded portion (32) of the pre-tightening valve seat (3) and the supporting valve seat (4).

2. The split valve seat plastic liner composite pressure vessel according to claim 1, characterized in that: The preload valve seat (3) and / or the support valve seat (4) are made of aluminum alloy, titanium alloy, stainless steel, carbon steel or plastic through a machining process.

3. The split valve seat plastic liner composite pressure vessel according to claim 1, characterized in that: The fiber reinforcement layer (2) is a solidified mixture of carbon fiber, glass fiber or Kevlar fiber and resin.

4. A method for manufacturing a split valve seat plastic liner composite pressure vessel according to claim 1, characterized in that: The following steps are involved: S1: applying adhesive to the outer surface of the recessed portion (11) of the plastic liner (1) and the flange portion (41) of the supporting valve seat (4), respectively, positioning the outer surface of the plastic liner (1) and the flange portion (41) of the supporting valve seat (4), and applying a pressing force until the adhesive is completely cured; S2: applying adhesive to the inner surface of the recessed portion (11) of the plastic liner (1) and the flange portion (31) of the pre-tightening valve seat (3), respectively, rotating the pre-tightening valve seat (3) so that the external threaded portion (32) of the pre-tightening valve seat (3) is connected to the supporting valve seat (4), applying a pre-tightening force so that the contact surfaces between the pre-tightening valve seat (3) and the plastic liner (1) are in contact with each other, and after the adhesive on the contact surface is cured, a press fit is achieved between the pre-tightening valve seat (3) and the plastic liner (1) under the action of the pre-tightening force; S3: welding the end cap of the plastic liner (1) to the cylinder portion of the plastic liner (1); S4: coating the outer surface of the container formed by the plastic liner (1) and the split valve seat with a transition agent, and winding a fiber reinforcement layer on the outer surface of the container; S5: placing the wound container in an oven and rotating and curing under pressure, and finally preparing a split valve seat fiber fully wound composite pressure vessel.

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