GB2058220A

GB2058220A - Flow fluctuation damper

Info

Publication number: GB2058220A
Application number: GB7931551A
Authority: GB
Original assignee: APV Corp Ltd
Current assignee: SPX Flow Technology Crawley Ltd
Priority date: 1979-09-11
Filing date: 1979-09-11
Publication date: 1981-04-08
Also published as: GB2058220B

Abstract

In order to reduce pulsations in a pipeline 1, a tube 2 is closed at its top end and filled with air in the space 3 between the liquid level 4 and the top end of the tube. The liquid level 4 is controlled by a probe 5, and when the liquid level reaches the probe an air supply is switched on to supply incoming air via an inlet line 7 which is helically coiled around the outside of the pipe 2 and within a steam jacket 10. The incoming air is thus sterilized before being released at the free open end of the line 7 within the space 3. In this way, a pre-set level of the liquid level 4 can be maintained and the sterility of the air within the space 3 is also maintained. To prevent possible thermal damage to the liquid flowing in the line 1, a considerable space is left between the bottom of the jacket 10 and the level 4. <IMAGE>

Description

SPECIFICATION Flow fluctuation damper This invention relates to dampers for reducing pulsations in pipelines, which pulsations may arise from the uneven flow inherent in reciprocating pumps, e.g. an homogenizer.

One known way of reducing the level of pulsations is to provide a so-called stand pipe, i.e.

a pipe extending upwardly from a pipeline, with air trapped in a cavity at the upper end of the pipe.

However, since the air trapped in the cavity is in contact with the flowing fluid, of which the pressure fluctuates, there is, in operation, a gradual loss of air from the cavity so that eventually the effectiveness of the damping is significantly reduced.

According to the present invention, there is provided a flow fluctuation damper comprising pipe adapted to extend upwardly from a liquid flow line and to have a column of air or other gas trapped between the flow line and a closed end of the pipe, the damper further including supply means for make-up air or gas to the column, and means for controlling the supply means in response to changes in the level of liquid in the pipe below the air column.

Where the liquid in the flow line is being processed under aseptic or sterile conditions, it is necessary to provide means for ensuring that the make-up air or gas is sterilized before admission to the column. To this end, the supply means may include a long, e.g. helically coiled, air supply duct contained in a steam jacket whereby the incoming air or gas is thermally sterilized prior to entry to the column. An aseptic filter may also be included in the supply means.

The steam jacket, for reasons of space economy is preferably arranged to surround part of the pipe and to ensure that thermal damage to the liquid in the flow line is minimised, a substantial space is preferably left between the jacket and the position of the liquid level near the lower end of the pipe.

The invention will be further described with reference to the accompanying drawing, of which the single figure is a diagrammatic section of a flow fluctuation damper according to a preferred embodiment of the invention.

A line for a liquid flow subject to fluctuation pressure is shown at 1, and extending generally vertically upwards therefrom is a so-called stand pipe 2 to receive a column of air in a space 3 extending from a desired level 4 of liquid extending up the stand pipe to a closed upper end of the stand pipe 2. In order to define the level 4, a liquid level probe 5 extends down the stand pipe 2 from the upper end, where it is connected into a control box 6 which transmits signals indicating the presence and/or absence of liquid at the lower end of the probe 5, which signals are used to control a supply of make-up air to the column within the space 3 of the stand pipe 2.

This make-up air is supplied via a duct 7 which is formed into a helical coil 8 extending over a substantial part of the length of the stand pipe 2 with its upper end indicated at 9 feeding into the interior of the stand pipe 2. This coil 8, and the associated part of the stand pipe 2 is enclosed within a steam jacket 10 having a steam entry 1 1 and exit 12, so that air passing up the coil 8 is subjected to steam heating so that it is sterilized before it enters the stand pipe via the entry 9.

Where necessary the interior of the stand pipe 3 is sterilised by the steam jacket and/or liquid in the flow line.

In addition, a sterilizing filter may be provided in the air supply line.

In order to prevent thermal damage to the liquid in the pipe 1, there is a substantial spacing between the lower end of the jacket 10 and the liquid level 4.

It will be seen that if the pressure of the liquid increases to a level where the liquid level 4 rises above the bottom of the probe 5, or if the air is absorbed in the flowing liquid, giving rise to the same position, the air supply will be switched on by the liquid level probe and make-up air supplied and sterilized.

Various modifications may be made within the scope of the invention.

1. A flow fluctuation damper comprising a pipe adapted to extend upwardly from a liquid flow line and to have a column of air or other gas trapped between the flow line and a closed end of the pipe, the damper further including supply means for make-up air or gas to the column, and means for controlling the supply means in response to changes in the level of liquid in the pipe below the air column.

2. A flow fluctuation damper as claimed in claim 1, wherein means is provided for ensuring that the make-up air or gas is sterilized before admission to the column.

3. A flow fluctuation damper as claimed in claim 2, in which the supply means also includes an aseptic filter.

4.-A flow fluctuation damper as claimed in claim 2 or 3, in which the supply means includes a air supply duct of extended length contained in a steam jacket whereby the incoming air or gas may be thermally sterilized prior to entry to the column.

5. A flow fluctuation damper as claimed in claim 4, in which the supply duct is helically or otherwise coiled in the steam jacket.

6. A flow fluctuation damper as claimed in claim 4 or 5, in which the steam jacket is arranged to surround part of the pipe.

7. A flow fluctuation damper as claimed in claim 6, in which a substantial space is left between the jacket and the position of the liquid level near the lower end of the pipe.

8. A flow fluctuation damper substantially as hereinbefore described with reference to the accompanying drawing.

New claims or amendments to claims filed on 4th August 1980.

Superseded claims: 1 to 8.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Flow fluctuation damper This invention relates to dampers for reducing pulsations in pipelines, which pulsations may arise from the uneven flow inherent in reciprocating pumps, e.g. an homogenizer. One known way of reducing the level of pulsations is to provide a so-called stand pipe, i.e. a pipe extending upwardly from a pipeline, with air trapped in a cavity at the upper end of the pipe. However, since the air trapped in the cavity is in contact with the flowing fluid, of which the pressure fluctuates, there is, in operation, a gradual loss of air from the cavity so that eventually the effectiveness of the damping is significantly reduced. According to the present invention, there is provided a flow fluctuation damper comprising pipe adapted to extend upwardly from a liquid flow line and to have a column of air or other gas trapped between the flow line and a closed end of the pipe, the damper further including supply means for make-up air or gas to the column, and means for controlling the supply means in response to changes in the level of liquid in the pipe below the air column. Where the liquid in the flow line is being processed under aseptic or sterile conditions, it is necessary to provide means for ensuring that the make-up air or gas is sterilized before admission to the column. To this end, the supply means may include a long, e.g. helically coiled, air supply duct contained in a steam jacket whereby the incoming air or gas is thermally sterilized prior to entry to the column. An aseptic filter may also be included in the supply means. The steam jacket, for reasons of space economy is preferably arranged to surround part of the pipe and to ensure that thermal damage to the liquid in the flow line is minimised, a substantial space is preferably left between the jacket and the position of the liquid level near the lower end of the pipe. The invention will be further described with reference to the accompanying drawing, of which the single figure is a diagrammatic section of a flow fluctuation damper according to a preferred embodiment of the invention. A line for a liquid flow subject to fluctuation pressure is shown at 1, and extending generally vertically upwards therefrom is a so-called stand pipe 2 to receive a column of air in a space 3 extending from a desired level 4 of liquid extending up the stand pipe to a closed upper end of the stand pipe 2. In order to define the level 4, a liquid level probe 5 extends down the stand pipe 2 from the upper end, where it is connected into a control box 6 which transmits signals indicating the presence and/or absence of liquid at the lower end of the probe 5, which signals are used to control a supply of make-up air to the column within the space 3 of the stand pipe 2. This make-up air is supplied via a duct 7 which is formed into a helical coil 8 extending over a substantial part of the length of the stand pipe 2 with its upper end indicated at 9 feeding into the interior of the stand pipe 2. This coil 8, and the associated part of the stand pipe 2 is enclosed within a steam jacket 10 having a steam entry 1 1 and exit 12, so that air passing up the coil 8 is subjected to steam heating so that it is sterilized before it enters the stand pipe via the entry 9. Where necessary the interior of the stand pipe 3 is sterilised by the steam jacket and/or liquid in the flow line. In addition, a sterilizing filter may be provided in the air supply line. In order to prevent thermal damage to the liquid in the pipe 1, there is a substantial spacing between the lower end of the jacket 10 and the liquid level 4. It will be seen that if the pressure of the liquid increases to a level where the liquid level 4 rises above the bottom of the probe 5, or if the air is absorbed in the flowing liquid, giving rise to the same position, the air supply will be switched on by the liquid level probe and make-up air supplied and sterilized. Various modifications may be made within the scope of the invention. CLAIMS

7. A flow fluctuation damper substantially as hereinbefore described with reference to the accompanying drawing.

New claims or amendments to claims filed on 4th August 1980.

Superseded claims: 1 to

8.

New or amended claims

1. A flow fluctuation damper comprising a pipe adapted to extend upwardly from a liquid flow line and to have a column of air or other gas trapped between the flow line and a closed end of the pipe, the damperfurtherincluding supply means for make-up air or gas to the column, means for controlling the supply means in response to changes in the level of liquid in the pipe below the air column, and means for sterilizing the make-up air or gas before admission to the column.

2. A flow fluctuation damper as claimed in claim 1, in which the sterilizing means includes an aseptic filter.

3. A flow fluctuation damper as claimed in claim 1 or 2, in which the supply means includes a air supply duct of extended length contained in a steam jacket whereby the incoming air or gas may be thermally sterilized prior to entry to the column.

4. A flow fluctuation damper as claimed in claim 3, in which the supply duct is helically or otherwise coiled in the steam jacket.

5. A flow fluctuation damper as claimed in claim 3 or 4, in which the steam jacket is arranged to surround part of the pipe.

6. A flow fluctuation damper as claimed in claim 5, in which a substantial space is left between the jacket and the position of the liquid level near the lower end of the pipe.