US3765246A

US3765246A - Fluid sampling device

Info

Publication number: US3765246A
Application number: US00209948A
Authority: US
Inventors: Coy J Mc
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-12-20
Filing date: 1971-12-20
Publication date: 1973-10-16
Anticipated expiration: 1990-10-16

Abstract

A fluid sampling device which is capable of delivering a sample of fluid in a closed, dry vessel which is free of contaminants on its outside surfaces. The sampling device is adapted to be inserted into the fluid flow system to assure sampling accuracy and to be completely withdrawn to leave the system undisturbed and unobstructed between sampling operations. The sampling device is so constructed that its operation is not inhibited by solid material in the fluid.

Description

United States Patent [191 McCo Oct. 16, 1973 FLUID SAMPLING DEVICE Primary ExaminerS. Clement Swisher [76] Inventor: James L. McCoy, Cap Negret l9, Attorney' olsen & Stephenson Altea, Spain [22] Filed: Dec. 20, 1971 [57] ABSTRACT [21] Appl. No.: 209,948 A fluid sampling device which is capable of delivering a sample of fluid in a closed, dry vessel which is free 52 .S. of Contaminants on its Outside surfaces The sampling g 8' 2 412 7 device is adapted to be inserted into the fluid flow system to assure p g accuracy and to be completely [58] Field of Search 73/422 TC withdrawn to leave the System undisturbed and unob [56] References Cited structed between sampling operations. The sampling device is so constructed that its operation is not inhib- UNITED STATES PATENTS ited by solid material in the fluid. 3,084,555 4/1963 Van Dop 73/422 9 Claims, 5 Drawing Figures PATENTEnnm 161975 3.765 246 SHEET 1 BF 2 I Z -/o FLUID SAMPLING DEVICE BACKGROUND OF THE INVENTION In treatment plants for waste or fresh water, continuous control of the process variables is essential to assure economy, quality, and uniformity in the process. Proper control of the treatment process can only be assured if accurate samples of the fluids in process can be collected. The collection of representative samples from various points in the treatment systems may be a difficult task due to the nature of the contents of the system. Many fluids encountered in sampling are not only unpleasant but are unsafe to handle.

The prior art is divided into dipper-type samplers for non-pressurized systems and valve-type samplers for pressurized and non-pressurized systems. The dippertype sampler depends on gravity for its operation and has drawbacks due to the likelihood of the dipper and the sample becoming contaminated. The dipping action tends to disturb the system and thus reduce the repeatability of sampling. Where valve-type samplers are utilized, the valve is merely opened and fluid is allowed to flow out into a receptacle in response to pressure differentials. The quantity of the sample is dependent on the system pressure and the consistency of the fluid sampled. Both parameters may fluctuate during processing. The valve is also susceptible to clogging when solid material is present. Eddy currents may be created by the flow at the valve inlet which would disturb the system and possibly yield erroneous samples.

SUMMARY OF THE INVENTION The present invention is suitable for both pressurized and nonpressurized systems and'overcomes the objections of the prior art.

A slidable piston assembly is mounted in a bore which communicates with the system to be sampled. The piston assembly reciprocates from a retracted position. to a sampling position and back during operation. The piston assembly has a sealing cylinder nested inside a concentric plunger. A cylindrical vessel of a given volume with a cylindrical cover is nested inside the concentric sealing cylinder. All the contiguous surfaces of the nested concentric cylinders are threaded and engage each other so the vessel, the cover, the sealing cylinder, and the plunger can move with respect to each other to provide the desired sampling function. The plunger and the vessel have apertures in their respective walls which align so that fluid can flow through the plunger and into the vessel when the sealing cylinder is retracted and the piston assembly is inserted into the fluid flow. Once the sample has flowed into the vessel, the sealing cylinder is advanced to close the apertures and clean solid materials from the seating surfaces around the apertures on the vessel. The cover is also advanced to close the apertures but the cover is iso lated from the fluid by a flange so that the cover is not contaminated on its outside surface by the fluid. Once the vessel is sealed off and covered, and the piston assembly has been retracted, the vessel and cover can be removed as a unit from the piston assembly for transfer or storage of the sample.

The sampler thus provides a safe, contaminant free container with a specific volume of fluid. The operation is unaffected by the presence of solid matter in the fluid. The sampler does not disrupt the system between sample operations.

Further objects, features and advantages of this invention will become apparent from a consideration of the following description, the appended claims, and the accompanying drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a side elevational view of the fluid sampling device of this invention installed on a conduit for sampling fluid flowing therein;

FIG. 2 is an enlarged sectional view of the device as seen along line 22 of FIG. 1 and showing the device in its loaded configuration;

FIG. 3 is a cross sectional view similar to FIG. 2 and shows the device in its ready configuration;

FIG. 4 is a cross sectional view similar to FIG. 2 and shows the device in its engaged position; and

FIG. 5 is a cross sectional view similar to FIG. 2 and shows the device in its sample position.

DESCRIPTION OF THE PREFERRED EMBODIMENT Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

Referring to the drawings, the fluid sampler 10 of this invention is shown in FIG. 1 attached to a conduit 12 for taking samples of fluid flowing in the conduit either under pressure or by gravity. The device 10 has a hollow body 14 which attaches to the conduit 12 to form a T-section with the conduit 12. The hollow body 14 has a bore 16, as shown in FIG. 2, which communicates with the conduit 12 at essentially a right angle to the center line of conduit 12.

The device 10 also includes a piston assembly 18 which is slidably supported for reciprocation within the bore 16. A retaining ring 19 is threaded onto the hollow body 14 to retain the piston assembly 18 within the bore 16. The piston assembly 18 includes a plunger 20 which is essentially cylindrical and has a smooth external surface 22 for sliding within bore 16. The plunger 20 is sealingly supported in the bore 16 against leakage by means of sealing rings 24. The plunger 20 has a lower end 28 with a concave surface 30 which forms a part of the conduit 12 when the piston assembly 18 is retracted, thus leaving the conduit opening free and unobstructed. The plunger 20 is hollow and has a threaded internal surface 32. A short internal cylinder 34 extends upward from the lower end 28. The short cylinder 34 has internal and external threaded surfaces 36 and 38 respectively. The purpose of the short cylinv der 34 will be explained presently. The plunger 20 also has side openings 40 transversely aligned with each other (FIGS. 2 and 5), only one of which is shown in the drawings. The piston assembly 18 also includes a sealing cylinder 42 with internal and external threaded

surfaces

44 and 46, respectively, which is nested within the plunger 20 so that relative rotation between the plunger 20 and the sealing cylinder 42 results in relative axial displacement. A collar 43, attached to one end 45 of the sealing cylinder 42, is provided so that the sealing cylinder 42 can be rotated by manipulation of the collar 43. The sealing cylinder 42 has an inwardly extending annular flange 48 near its lower end. The annular flange 48 has an internal threaded surface 50. When the sealing cylinder 42 is in its lowest position as shown in FIG. 2, the annular flange 48 is seated against the top of the short cylinder 34 and the threaded surfaces 36 and 50 form a continuous thread bore 52.

The device also includes a cover 54 in the form of a hollow cylinder with internal and external threaded

surfaces

56 and 58, respectively, which is nested within the sealing cylinder 42 above the annular flange 48 so that relative rotation between the sealing cylinder 42 and the cover 54 results in relative axial displacement. A collar 55, attached to one end 57 of the cover 54, is provided so that the cover 54 can be rotated by manipulation of the collar 55. When the cover 54 is in its lowest position as shown in FIG. 2, it is seated against the annular flange 48 and its internal surface 56 aligns with surface 50 of the annular flange 48 to form an extension of continuous thread bore 52.

The device 10 also includes a vessel 60 in the form of a cylinder with external threaded surface 62 sized to be threaded into the internal threaded surface 56 of cover 54 and continuous thread bore 52. A collar 61, attached to one end 63 of the vessel 60, is provided so that the vessel 60 can be rotated by manipulation of the collar 61. The vessel 60 has an internal cylinder 61 with transversely aligned inlet ports 64, only one of which is shown in the drawings. The chamber 61 is configured so that it is larger than ports 64, thus forming faces 65 inside the chamber 61 around each port 64. The inlet ports 64 are situated so as to align with side openings 40 when the vessel 60 is in its lowest position, as shown in FIGS. 3-5. In this lowest position, the external threads 62 of vessel 60 are threaded into the internal threads 36 of short cylinder 34. A seal is thus provided between the fluid in conduit 12 and the bottom surface 66 of vessel 60 which is seated against seating surface 68 on the lower end 28 of plunger 20.

In operation, assume that the device 10 is in its loaded configuration as shown in FIG. 2 in which the plunger is retracted and the sealing cylinder 42 and the cover 54 are in their lowest position to form the continuous thread bore 52. The vessel 60 is then rotated so as to thread it downwardly to a position in which its bottom surface 66 is seated against the seating surface 68 on lower end 28 of the plunger 20. The device 10 is now in its ready configuration as shown in FIG. 3. A force is then applied to the plunger 20 so as to move the piston assembly 18 downwardly into the conduit 12 so as to project the plunger 20 into the fluid in the stream to be sampled. The device 10 is now in its engaged position as shown in FIG. 4. In this position of the device 10, fluid in the conduit 12 cannot enter the chamber 61 in the vessel 60 because the sealing cylinder 42 overlies the inlet ports 64 for the chamber 61.

The sealing cylinder 42 is then threaded upwardly in the plunger 20, without moving the vessel 60 or the plunger 20, so as to simultaneously raise both sealing cylinder 42 and cover 54 to place the device 10 in its sample position as shown in FIG. 5. In this position of the device 10, fluid in the conduit 12 can flow into the vessel chamber 61 through the aligned side openings 40 and inlet ports 64 in the plunger 20 and the vessel 60 respectively.

After the expiration of a time period sufficient to fill the chamber 61, the sealing cylinder 42 and the cover 54 are threaded downwardly to the positions shown in FIG. 4 in which they close and seal the inlet ports 64. During movement of the cylinder 42 and the cover 54 along the external threaded surface 62 of the vessel 60, the cover 54 and the sealing cylinder 42 act also to clean and remove all foreign material from the external surface 62 of the vessel 60. It is to be noted that the external threaded surface 58 of the cover 54 and the bottom surface 66 of the vessel 60 have at all times been prevented from contacting fluid in the conduit 12.

After the inlet ports 64 have been closed and sealed by the sealing cylinder 42, the piston assembly 18 is retracted to the position shown in FIG. 3. The vessel 60, filled with fluid from conduit 12 is then rotated upwardly to the position shown in FIG. 2 in which the inlet ports 64 are sealed by the cover 54. The cover 54, supporting the vessel 60, is then rotated upwardly out of the sealing cylinder 42 and removed from the piston assembly 18. The fluid in the chamber 61 can then be stored or transferred without any danger that the fluid in the chamber 61 will be contaminated or exposed. During storage and transfer, the container formed by the vessel 60 and the cover 54 is sealed and the external surfaces of the container are free of contamination by the fluid in the conduit 12 so that the container can be freely handled.

A second cover 54, supporting another vessel 60, can then be threaded into the sealing cylinder 42 and the above sequence can be repeated when desired to obtain another sample of fluid from conduit 12.

What is claimed is:

l. Fluid sampling apparatus for extracting a discrete sample of fluid from a fluid containing member, said apparatus comprising a plunger having an axis, means supporting said plunger for movement in a direction axially thereof between a retracted position and a position projecting into said fluid containing member, said plunger having a side opening therein, a vessel having an internal chamber and side entrance port means communicating therewith, means mounting said vessel in said plunger for movement in a direction extending axially of said plunger to a position in which said port means communicates with said plunger opening so that fluid can flow into said chamber in said projecting position of said plunger, and means on said vessel operable to close said port means and support said vessel for removal from said plunger.

2. The fluid sampling apparatus that is defined in claim 1, wherein said means supporting said plunger is a hollow body member having an essentially cylindrical bore and said vessel, said plunger, and said means mounting said vessel in said plunger are essentially cylindrical in shape, are nested within each other and within said bore, and are axially movable with respect to each other.

3. Fluid sampling apparatus according to claim 2 wherein said fluid containing member is a conduit of substantially circular cross section having an axis extending normal to said plunger axis, said plunger having a concave face closing the lower end of said body member bore in said retracted position of said plunger.

4. Fluid sampling apparatus according to claim 1 wherein said means mounting said vessel in said plunger includes a cylindrical sealing member arranged in a removable covering relation with said vessel support means so as to protect said vessel support means against Contact with said fluid.

5. The fluid sampling apparatus that is defined in claim 4, wherein said plunger is hollow and cylindrical in shape and has a threaded bore with a closed end and an open end, said sealing member is hollow and cylindrical in shape and has a threaded external surface engageable within said threaded bore of said plunger and a threaded internal bore with both ends thereof open, said vessel support means is hollow and cylindrical in shape and has a threaded external surface engageable within said threaded bore of said sealing member and a threaded bore with both ends thereof open, and said vessel has a threaded external surface engageable within said threaded bore of said vessel support means.

6. The fluid sampling apparatus that is defined in claim 5 wherein said port means and said side opening are in communication when said vessel is seated against said closed end of said plunger.

7. Fluid sampling apparatus according to claim 6 wherein said closed end of said plunger has an internally threaded projection aligned with the internally threaded bore of said vessel support means so that said vessel can be threaded into said internally threaded projection to a stop position engaged with said closed end.

8. The fluid sampling apparatus that is defined in claim 7 wherein said sealing member has a radially inwardly directed flange having a threaded internal surface aligned with and positioned between said internally threaded projection on said closed end of said plunger and the threaded bore in said vessel support means.

9. The fluid sampling apparatus that is defined in claim 8 wherein said vessel is adapted for retraction into said support means so that said support means and said vessel can be removed as a unit from said plunger.

Claims

1. Fluid sampling apparatus for extracting a discrete sample of fluid from a fluid containing member, said apparatus comprising a plunger having an axis, means supporting said plunger for movement in a direction axially thereof between a retracted position and a position projecting into said fluid containing member, said plunger having a side opening therein, a vessel having an internal chamber and side entrance port means communicating therewith, means mounting said vessel in said plunger for movement in a direction extending axially of said plunger to a position in which said port means communicates with said plunger opening so that fluid can flow into said chamber in said projecting position of said plunger, and means on said vessel operable to close said port means and support said vessel for removal from said plunger.