Shear valve with silicon carbide member

Patent metadata

Field	Value
Publication number	US-9316324-B2
Application number	US-60672609-A
Country	US
Kind code	B2
Filing date	Oct 27, 2009
Priority date	Oct 29, 2008
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

A shear valve, for use in a high performance liquid chromatography system, comprises a first shear valve member and a second shear valve member. At least one of the first and second shear valve members is adapted to be moved with respect to the other. One of the first and second shear valve members comprises a plurality of ports, and the other comprises at least one fluid path for fluidly coupling respective ones of the ports in dependency on a relative movement position of the first and second shear valve members with respect to each other. The first shear valve member is at least partially coated with or comprised of silicon carbide.

First claim

The invention claimed is:

1. A shear valve for use in a high performance liquid chromatography system, the shear valve comprising:
a first shear valve member;
a second shear valve member; and
a housing for housing one of the first and the second shear valve members, wherein the housing is shrink-fit to the one of the first and second shear valve members and is prestressed against the housed shear valve member to achieve sealing in pressurized applications,
wherein at least one of the first and second shear valve members is configured to be moved with respect to the other, one of the first and second shear valve members comprises a plurality of ports, and the other comprises at least one fluid path for fluidly coupling respective ones of the ports in dependency on a relative movement position of the first and second shear valve members with respect to each other,
wherein the first shear valve member is at least partially coated with or comprised of a ceramic material.

2. The shear valve of claim 1 , wherein the ceramic material is a sintered silicon carbide material.

3. The shear valve of claim 1 , wherein the shear valve is a rotary valve, and the first and the second shear valve members are rotatably movable with respect to each other.

4. The shear valve of claim 1 , wherein the shear valve is a translational valve, and the first and the second shear valve members are translationally movable with respect to each other.

5. The shear valve of claim 1 , wherein the second shear valve member is at least partially coated with or comprised of a material tribologically matching to the first shear valve member.

6. The shear valve of claim 1 , wherein the second shear valve member is at least partially coated with or comprised of at least one of: a polymer material, polyetheretherketone (PEEK), a blend of PEEK/PBI (polybenzamidazole), PTFE (polytetrafluoroethylene), molybdenum disulfide, titanium dioxide, carbon, and nano-particles, SSiC, SiC, SSiC CVD coated, a blend of PEEK/PBI/PTFE, a blend of PEEK/PBI/Carbon/PTFE, and a blend of PEEK/PBI/Carbon/TlO 2 /PTFE.

7. The shear valve of claim 1 , wherein
the first shear valve member is the housed shear valve member; or
the housing is made of or comprises at least one of: a stainless steel, a DLC coated stainless steel, SiC, SSiC, or SiC CVD coated.

8. The shear valve of claim 1 , wherein the fluid path comprises a groove.

9. The shear valve of claim 1 , wherein one or more of the ports comprise a through hole having an opening fluidly coupling with the fluid path dependent on the moving position.

10. The shear valve of claim 1 , wherein
the first shear valve member comprises the plurality of ports, and
the second shear valve member comprises the at least one fluid path for fluidly coupling respective ones of the ports of the first shear valve member in dependency on a relative movement position of the first and second shear valve members with respect to each other.

11. The shear valve of claim 1 , wherein the second shear valve member is configured to be moved with respect to the first shear valve member.

12. The shear valve of claim 1 , further comprising at least one of:
a drive for moving the one of the first and second shear valve members to be moved; and
a valve control unit configured to control a movement of the first and second shear valve members with respect to each other.

13. The shear valve of claim 1 , wherein
the shear valve is configured to conduct a liquid in the at least one fluid path at a high pressure at which compressibility of the liquid becomes noticeable, or
the shear valve is configured to conduct a liquid in the at least one fluid path at a high pressure in a range of 20-200 MPa, and particularly 50-120 MPa.

14. The shear valve of claim 1 , wherein the shear valve is one of:
a sample injection valve for injecting a liquid sample into a high pressure flowing stream of liquid;
a high-pressure purge valve for a positive displacement pump; or
a flow path switching valve for switching from one flow path to another flow path.

15. A sample injector configured to introduce a sample fluid into a mobile phase, wherein the mobile phase is driven by a mobile phase drive through a separation unit for separating compounds of the sample fluid in the mobile phase, the sample injector comprising:
a sample loop for receiving the sample fluid, and
the shear valve of claim 1 for switching the sample loop between the mobile phase drive and the separation unit.

16. A fluid separation system for separating compounds of a sample fluid in a mobile phase, the fluid separation system comprising:
a mobile phase drive configured to drive the mobile phase through the fluid separation system,
separation unit, preferably a chromatographic column, configured to separate compounds of the sample fluid in the mobile phase, and
the shear valve of claim 1 for switching from one flow path to another flow path within a fluid separation flow path between the mobile phase drive and the separation unit.

17. The fluid separation system of claim 16 , further comprising at least one of:
a sample injector configured to introduce the sample fluid into the mobile phase;
a detector configured to detect separated compounds of the sample fluid;
a collection unit configured to collect separated compounds of the sample fluid;
a data processing unit configured to process data received from the fluid separation system; or
a degassing apparatus for degassing the mobile phase.

Assignees

• Berndt Manfred
• Agilent Technologies Inc

Inventors

• Berndt Manfred

Classifications

• Y10T137/86863

  Rotary valve unit · CPC title

• F16K25/005

  Particular materials for seats or closure elements · CPC title

• G01N2030/202

  rotary valves · CPC title

• F16K11/074 Primary

  with flat sealing faces · CPC title

• B01D15/16

  relating to the conditioning of the fluid carrier · CPC title