Valve stem with head covered by covering material and method of making valve stem

• US 10,612,671 B2
• Filed: 04/30/2018
• Issued: 04/07/2020
• Est. Priority Date: 04/30/2018
• Status: Active Grant

• Current Assignee: Alfa Laval Shell, Inc.
• Original Assignee: DSO Fluid Handling Co., Inc. (ALFA Laval AB)
• Inventors: Kotarski, Ed, Cabrera, Joel
• Primary Examiner(s): Murphy, Kevin F
• Application Number:
  US15/967,388
• Publication Number:
  US 20190331232A1
• Time in Patent Office: 708 Days
• Field of Search: 251357
• CPC Class Codes: B23P 15/001 valves or valve housings welding B23K; valve housings per se F16K
• CPC Class Codes: B29C 43/006 Pressing and sintering powders, granules or fibres
• CPC Class Codes: B29C 43/14 in several steps
• CPC Class Codes: B29C 43/18 incorporating preformed parts or layers, e.g. compression moulding around inserts or for coating articles B29C43/206 takes precedence
• CPC Class Codes: B29K 2027/18 PTFE, i.e. polytetrafluorethene , e.g. ePTFE, i.e. expanded polytetrafluorethene
• CPC Class Codes: B29K 2705/00 Use of metals, their alloys or their compounds, for preformed parts, e.g. for inserts
• CPC Class Codes: B29L 2031/7506 Valves
• CPC Class Codes: B29L 2031/773 Dome-shaped igloos B29L2031/106, frameless domes B29L2025/00
• CPC Class Codes: F16K 1/36 Valve members for double-seat valves F16K1/44 ; for butterfly valves F16K1/222, F16K1/223
• CPC Class Codes: F16K 1/46 Attachment of sealing rings
• CPC Class Codes: F16K 1/487 by a fixing element extending in the axial direction of the spindle, e.g. a screw
• CPC Class Codes: F16K 25/005 Particular materials for seats or closure elements
• CPC Class Codes: F16K 41/04 with at least one ring of rubber or like material between spindle and housing

Abstract

A valve head engageable and disengageable with a valve seat of a valve comprises a valve body that includes a recess, a disk at one axial end of the recess and a flange at the other axial end of the recess so that the recess is positioned axially between a portion of the disk and a portion of the flange. The outermost portion of the flange extends outwardly beyond the outermost portion of the disk. A covering made of a material different from and more elastic than the material forming the valve body entirely covers the disk. A portion of the covering is positioned in the recess to mechanically connect the covering to the valve body. The outermost portion of the flange is in direct contact with the covering.

Claims

1. A valve stem movable into engagement with a valve seat of a valve to close a passageway defined by the valve seat and prevent fluid flow through the passageway and movable out of engagement with the valve seat of the valve to open the passageway defined by the valve seat to permit fluid flow through the passageway, the valve stem comprising:

a one-piece valve body made of metal, the one-piece metal valve body including a portion that is recessed to define a recess in the valve body, the recess possessing opposite axial ends, the one-piece metal valve body also including a disk positioned at one of the axial ends of the recess and a flange positioned at the other of the axial ends of the recess, the recess being positioned axially between a portion of the disk and a portion of the flange, the flange and the disk each including an outermost portion, the outermost portion of the flange extending outwardly beyond the outermost portion of the disk;

an elongated stem connected to the valve body and extending in a direction away from the flange, the outermost portion of the flange and the outermost portion of the disk extending outwardly beyond an outermost portion of the elongated stem; and

a covering compression molded onto the valve body, the covering made of a material different from and more elastic than the metal forming the one-piece valve body, the covering comprising polytetrafluoroethylene, the covering comprised of the polytetrafluoroethylene entirely covering the disk, a portion of the covering comprised of the polytetrafluoroethylene being positioned in the recess to mechanically connect the covering to the valve body, the outermost portion of the flange being in direct contact with the covering comprised of the polytetrafluoroethylene.

2. The valve stem of claim 1, wherein the metal forming the one-piece valve body comprises steel.

3. The valve stem of claim 1, wherein the outermost portion of the flange is thinner than a portion of the flange positioned inwardly of the outermost portion of the flange.

4. The valve stem of claim 1, wherein the valve body further includes a connection portion projecting axially away from the flange, the elongated stem being connected to the connection portion.

5. The valve stem of claim 4, wherein the connection portion comprises a hollow cylinder defining a female thread threadedly connected to a male thread of the elongated stem.

6. The valve stem of claim 1, wherein the outermost portion of the flange is bent or curved toward the covering.

7. A valve head engageable with a valve seat of a valve to close a passageway defined by the valve seat and prevent fluid flow through the passageway and movable to be disengaged from the valve seat of the valve to open the passageway defined by the valve seat to permit fluid flow through the passageway, the valve head comprising:

a valve body made of a first material and including a dome-shaped portion, a cylindrical portion, and a flange portion, the cylindrical portion being positioned axially between the dome-shaped portion and the flange portion;

the dome-shaped portion, the cylindrical portion and the flange portion each possessing an outermost diameter;

the outermost diameter of the dome-shaped portion being greater than the outermost diameter of the cylindrical portion and less than the outermost diameter of the flange portion;

the dome-shaped portion being disposed at a first end of the cylindrical portion and the flange portion being disposed at a second end of the cylindrical portion opposite the first end so that the cylindrical portion is positioned axially between the dome-shaped portion and the flange portion; and

a covering made of a second material, the second material being more elastic than the first material, the covering being compression molded onto the valve body and entirely covering the domed-shaped portion and the cylindrical portion.

8. The valve head of claim 7, wherein the first material comprises steel.

9. The valve head of claim 7, wherein the second material comprises polytetrafluoroethylene.

10. The valve head of claim 7, wherein the valve body further includes a connection portion disposed at the second side of the cylindrical portion, the connection portion being configured to connect the valve head to an elongated stem.

11. The valve head of claim 10, wherein the connection portion comprises a hollow cylinder that includes a female thread.

12. The valve head of claim 7, wherein the flange portion possesses an outer periphery that is bent or curved toward the covering and in direct contact with the covering.