Hygienic tank seal

Patent metadata

Field	Value
Publication number	US-11965767-B2
Application number	US-201917604534-A
Country	US
Kind code	B2
Filing date	Apr 23, 2019
Priority date	Apr 23, 2019
Publication date	Apr 23, 2024
Grant date	Apr 23, 2024

Abstract

A guided wave radar level gauge adapted for mounting on a nozzle of a tank, including an attachment collar with an opening configured to be aligned with the nozzle and to be secured by means of an annular clamping device, and a transmission line probe attached to an exterior end of a probe connector. The GWR level gauge further comprises an annular sealing gasket fitted in the collar opening, the annular sealing gasket having a central opening through which the central probe connector extends, and a distancing sleeve arranged around the exterior end of the probe connector and having a radially protruding collar portion, wherein processing circuitry is configured to detect an impedance change caused by tank content or condensate which has passed through the central opening of the sealing gasket and collected in an annular space immediately surrounding the radially protruding collar portion.

First claim

The invention claimed is:

1. A guided wave radar level gauge for determining the filling level of product in a tank, said level gauge being adapted for mounting on a nozzle of a tank, said level gauge comprising:
transceiver circuitry configured to generate and transmit an electromagnetic transmit signal S T and receive an electromagnetic return signal S R from the tank, the electromagnetic return signal caused by a reflection from a surface of said product,
a transmission line probe electrically connected to said transceiver circuitry, said probe in use extending from the level gauge to a bottom of the tank, and being adapted to allow the microwave transmit signal to propagate along the probe toward said product and return the electromagnetic return signal,
processing circuitry configured to determine the distance between a reference position and the surface of the product based on a relationship between the transmit signal and the return signal,
an attachment collar with an opening configured to be aligned with the nozzle and to be secured by means of an annular clamping device, and
a coaxial probe connection comprising a central probe connector suspended in a dielectric sleeve mechanically secured in the attachment collar, said central probe connector having an exterior end extending outside the dielectric sleeve beyond said collar opening, wherein said probe is attached to said exterior end of the probe connector,
characterized by:
an annular sealing gasket fitted in said collar opening, said annular sealing gasket having an outer periphery configured to be sandwiched between the attachment collar and a flange of said nozzle, and a central opening through which said central probe connector extends, and
a distancing sleeve arranged around the exterior end of the probe connector, said distancing sleeve having a radially protruding collar portion between the dielectric sleeve and the sealing gasket, such that, when the probe is attached to the probe connector, an inner periphery of the sealing gasket will be sandwiched between the radially protruding collar portion and an end of the probe,
wherein said processing circuitry is configured to detect an impedance change caused by tank content or condensate which has passed through the central opening of the sealing gasket and collected in an annular space immediately surrounding said radially protruding collar portion.

2. The gauging instrument according to claim 1 , wherein the annular clamp is a tri-clamp.

3. The level gauge according to claim 1 , wherein the attachment collar includes:
an annular sealing surface,
an annular abutment surface located radially outside said sealing surface and configured to abut an outer periphery of the tank nozzle, and
a ridge located radially outside said abutment surface;
such that, when the gauging instrument is mounted on a tri-clamp flange of a tank nozzle, said ridge surrounds the outer periphery of the tri-clamp flange to thereby ensure radial alignment, said annular abutment surface abuts the periphery of the tank nozzle to ensure a precisely defined axial relation, and the sealing gasket is sandwiched between said sealing surface and the tri-clamp flange.

4. The gauging instrument according to claim 1 , wherein the nozzle flange is provided with an annular groove, and wherein the sealing gasket comprises an annular protrusion configured to be received in said groove.

5. The gauging instrument according to claim 1 , wherein the sealing gasket is made of rubber.

6. The gauging instrument according to claim 1 , wherein a gap is formed radially outside the sealing gasket.

Assignees

• Rosemount Tank Radar Ab

Inventors

• Fredriksson Håkan
• Lindblad Björn
• Eriksson Mikael

Classifications

• G01F23/284 Primary

  Electromagnetic waves · CPC title

• F16L23/003

  Auxiliary devices · CPC title

• F16L23/08

  connection by tangentially arranged pin and nut · CPC title

• F16L23/22

  made exclusively of a material other than metal · CPC title

• F16L41/008

  for connecting a measuring instrument · CPC title