MONOBLOCK BALL VALVE AND MANUFACTURE METHOD THEREOF

• US 20110017932A1
• Filed: 03/07/2008
• Published: 01/27/2011
• Est. Priority Date: 03/07/2008
• Status: Abandoned Application

• Current Assignee: Celula 3PP, S.A.
• Original Assignee: Celula 3PP, S.A.
• Inventors: Domingues Matos, Arnaldo
• Application Number:
  US12/921,371
• Publication Number:
  US 20110017932A1
• Time in Patent Office: Days
• US Class Current: 251/315.16
• CPC Class Codes: B29C 2045/1601 the injected materials not being adhered or bonded to each other B29C45/0017 takes precedence
• CPC Class Codes: B29C 45/0017 moulding interconnected elements which are movable with respect to one another, e.g. chains or hinges
• CPC Class Codes: B29C 45/14754 being in movable or releasable engagement with the coating, e.g. bearing assemblies
• CPC Class Codes: B29C 45/1704 the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles B29C45/1732 and B29C45/1734 take precedence; injection blow-moulding B29C49/06
• CPC Class Codes: B29C 45/4421 using expansible or collapsible cores
• CPC Class Codes: B29C 45/4457 using fusible, soluble or destructible cores
• CPC Class Codes: F16K 27/067 with spherical plugs

Abstract

A manufacture method of monoblock ball valve is based on overmoulding techniques and integral assembly of plastic components inside the injection moulds, in a sequential manufacturing process, wherein the component which is injected in the first stage of the process will be sequentially introduced in moulds which will in turn inject other components, thus resulting in the end in a single body that ensures the functional features of a piece obtained by several components'"'"' assembly. The hydraulic ball valve according to the invention comprises at least the following components: a ball filling element or valve filling core with a valve control stem,—a ball that involves the ball filling element; a sleeve-type sealing element, which covers the entire ball and the whole interior part of the valve body, and a valve body.

Claims

1. A manufacture method of monoblock ball valves, wherein its components are overmoulded onto each other in a mould with several cores or in successive moulds, forming a single and solid body, comprising sequence injection moulding, wherein each subsequent component is injected onto the previous component thus involving it, wherein the following components are moulded at least in the following order:

A ball filling element with a valve control stem;

A ball which is moulded onto the ball filling element;

A single sealing element which involves the ball and the inside of the valve, also promotes the sealing at the stem and at the valve'"'"'s inlet and outlet area; and

A valve body.

2. The manufacture method according to claim 1, wherein the ball filling element integrated with the stem is produced by methods such as:

lost-core injection, by introducing mechanisms in the mould such as retractile cores, gas or water assisted injection, by using foaming or nucleation agents or even being injected and submitted to surface finishing procedures to remove imperfections, being later assembled into the sealings and overmoulded with the valve body, thus forming a single body.

3. The manufacture method according to claim 1, wherein the ball being integrated with the ball filling element, produced by methods such as:

gas or water assisted injection, or using foaming agents allowing the combination in a single piece, the ball and the ball filling element, eliminating a component of the process.

4. The manufacture method according to claim 1, wherein the overmoulded ball has an uniform thickness, preferably a thickness between 2.5 mm to 3 mm, which doesn'"'"'t compromise its mechanical performance.

5. A manufacture method according to claim 1, wherein the ball and filling element, are manufactured by the following processes:

as lost-core injection, by introducing mechanisms in the mould such as retractile cores, gas or water assisted injection or by using foaming or nucleation agents wherein the ball filling element is replaced by an equivalent piece produced in material that can later be removed, such as;

low melting-point metal or soluble polymers with the aim of removing thickness from the ball.

6. The manufacture method according to claim 1, further comprising a rotative mechanism of the valve ball inside the injection mould of the valve body and wherein the rotation of the ball is carried out, even still in hot conditions.

7. The manufacture method according to claim 6, wherein the rotative mechanism of the valve ball inside the injection mould of the valve body consists of a hydraulic cylinder that is fixed in the lower side of the mould, a rack that drives the toothed wheel (connected to the piston rod of the hydraulic cylinder already inside the mould), an associated toothed wheel (driven by the rack) and finally the rotative core associated with the toothed wheel, that promotes the connection of the stem, thus rotating the ball.

8. The manufacture method according to claim 1, wherein an innocuous and volatile substance or a slip-type antiadherent mould-removable substance is applied around the ball when the component passes from the ball into the mould that will inject the sealing element.

9. The manufacture method according to claim 1, wherein internal reinforcements and are introduced over the sealing element or over the ball seats.

10. The manufacture method according to claim 1, wherein the partition line (x) of all moulds, is placed in a central position to the diameter of the ball body and aligned in the direction of the fluid'"'"'s passage opening.

11. Monoblock ball valve manufactured according to the method of claim 1, comprising at least the following components:

a ball filling element with a valve control stem, which has an essentially spherical shape with a cylindrical channel whose axis crosses the ball centre and is essentially transversal to the control stem'"'"'s axis;

a ball with a hollow spherical shape that involves the ball filling element;

a single sleeve-type sealing element involving the entire ball and the whole internal part of the valve, comprising two cylindrical-section openings coincident to the inlet and outlet areas of the valve body, the said sleeve having a sealing element opening in the area involving the diameter of the stem; and

a valve body with an essentially cylindrical hollow shape, comprising inlet and outlet areas in its ends and a radial opening in the middle of the body for the rolling passage of the stem, wherein quick coupling systems are provided both in the inlet and outlet areas.

12. The valve according to claim 11, wherein the quick coupling systems of the valve body comprise in its inlet and outlet areas:

an abutment element of the sealing with an essentially annular shape comprising a recto radial abutment surface which receives the end of the tube in its interior and abuts it to the valve body close to the end of the sealing element, and has a longitudinal extension to hold the o-ring and the tube clamping element;

an o-ring that is assembled in the grove of the abutment element of the sealing;

a tube clamping element, essentially conical and annular-shaped and extending longitudinally, comprising teeth in the interior surface and a slot projected in order to reduce its diameter and to absorb variations in the tubes'"'"' diameter; and

an essentially annular-shaped nut extending longitudinally which comprises an interior thread in one end that will promote the coupling to the valve body as well as a conical interior surface which by being clamped, presses the abutment element of the sealing and the o-ring against the wall and the tube clamping element close so as to press the teeth against the tube.

13. The valve according to claim 11, wherein the longitudinal movement of the nut is absorbed by flexible abutment tabs located in the contact area with the abutment element of the sealing and also by flexible abutment tabs in the end of tube clamping element.

14. The valve according to claim 11, wherein the tube clamping element comprises a metal washer, that substitutes one of its teeth and carries out fastening/indentation of hard tubes, in high-pressure applications.

15. The valve according to claim 11, further comprising an anti-particle filter inside the valve body.

16. The valve assembly according to claim 12, further comprising the following stages:

assembling up the o-ring in the grove of the abutment element of the sealing;

assembling the tube clamping element in the abutment element of the sealing

slipping on the tube clamping element in the nut;

starting the nut clamping such that the o-ring and the abutment element of the sealing are not yet pressed;

introducing the tube until it leans against the bottom surface of the abutment element of the sealing;

proceeding with the nut clamping until the abutment element of the sealing is adjusted and pressed against the wall of the sealing.

17. The valve according to claim 11, wherein the convectional coupling system of the valve body comprise in the inlet and outlet areas:

an essentially annular-shaped end-element (connector) extending longitudinally, wherein the tube is attached by gluing, welding, threading or thermofusion, which receives the end of the tube in its interior and leans against the valve body at the end of the sealing element;

an essentially annular-shaped nut extending longitudinally, which comprises an interior thread in one end that will promote the coupling to the valve body, as well as an interior surface corresponding to the shape of the end-element of the tube.

18. The valve according to claim 11, wherein the ball filling element and the ball are made of a material consisting of a certain chemical affinity, preferably Polypropylene, PVC, PVDF, PPSU, PSU, ABS, POM and PEx.

19. The valve according to claim 11, wherein the single sealing element is made of a TPE—

thermoplastic elastomer, with compositions that might have thermoplastics or thermosettings as base matrix, such as Polypropylene (PP), Polyethylene (PE), Polyester (UP), Polyamide (PA), Silicone (SI) and Polyester (UP), preferably TEEE polyester based thermoplastic rubber.

20. The valve according to claim 11, wherein the valve body is made of PVC-U, PVC-C, PVDF, PP-H, PP-R, PP-R+30% GF, PP-CRT, ABS, PSU, PPSU, PE, PEx, POM, PPO, or others.