US2693705A - Liquid sampler - Google Patents

Description

NOV. 9, 1954- A CASLER ET AL 2,693,705

LIQUID SAMPLER Filed April 13, 1955 3 Sheets-Sheet l 24 I H" I MW" WM aff/ey Nov. 9, 1954 L A, CASLER ETAL LIQUID SAMPLER 3 Sheets-Sheet 2 Filed April 13, 1953 FUE. E

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NOV. 9, 1954 1 A CASLER ETAL 2,693,705

LIQUID SAMPLER Filed April 13, 1953 3 Sheets-Sheet 3 United States Patent C LIQUID SAMPLER John A. Casler, Royal Oak, Mich., and Harry O. Smith, Lester F. Coleman, and Milton Levenson, Chicago, Ill., assignors to the United States of America as represented by the United States Atomic Energy Commission Application April 13, 1953, Serial No. 348,196

1 Claim. (Cl. 73-421) This invention relates to an apparatus for transferring liquid from one container to another. More particularly it pertains to apparatus for handling samples of radioactive, poisonous, or valuable liquids, for analytical purposes.

The handling of liquid samples for analytical purposes creates various problems. Where the liquids are poisonous or radioactive, precautions must be taken to safeguard personnel. Leakage and unsafe equipment cannot be tolerated. Where the liquids are valuable in themselves, it is apparent that losses cannot be sustained for long. The need for leakproof equipment as well as careful technique is recognized beyond doubt.

One object of this invention is the handling of radioactive liquids without risk of contamination due to leakage.

Another object is the prevention of `loss of valuable liquids.

Still another object is the return of the liquid sample upon completion of the analysis.

in the drawings:

Fig. l is a vertical sectional View of the sampler showing the manner in which it is connected to a source tank of liquid to be sampled;

Fig. 2 is a horizontal sectional view of the sampler taken on the line 2 2 of Fig. l;

Fig. 3 is a vertical sectional view of the sampler taken on the line 3 3 of Fig. 2;

Fig. 4 is a vertical sectional view taken on the line 4 4 of Fig. 2;

Fig. 5 is a vertical sectional View of a support member taken on the line 5 5 of Fig. 2; and

Fig. 6 is a horizontal sectional view taken on the line 6 6 of Fig. 5.

As shown in Fig. l a sampler, generally lindicated at 10, is enclosed within a rectangular housing 12. Within the housing 12 are disposed the operating parts which are connected to a source tank 14 of liquid 16 to be sampled by means of an inlet pipe or tube 18 and an outlet pipe or tube 20. The side of the housing 12 facing the source tank 14 is provided with an upper flat 22 and a lower ap 24 both of which are apertured (Fig. 3) for attachment of the sampler to an upright support member (not shown).

Referring to Figs. 2, 3, and 4, the housing 12 vencloses two separate sampler units which are independently operated. For the purpose of explanation only one of the units will be described in detail, namely, the unit on the right as shown in the drawings, it being understood that the other unit corresponds thereto. Referring to Fig. l the sampler unit to be described is supported by the housing 12 by means of a cylindrical support 'member 26 the upper end of which is fastened to the top of the housing by a screw 28. The lower end of the member 26 is externally threaded at 30 for the attachment of a retainer nut 32 to be described in greater detail below. As shown in Figs. 5 and 6, the lower end of the member 26 is provided with a recess 34. Two bores 36 and 38 extend from the recess 34 generally longitudinally of the member 26 for a short distance. The end of the bore 36 remote from the recess 34 connects with a passage 40 which extends transversely through the member. For ease of fabrication the passage 40 is inclined at an angle of 85 to the bore 36. The bore 38 makes communication with a passage 42, which, as shown in Figs. 5 and 6, extends from the upper end of the bore 38 to the exterior of ice y the support 26 in a direction transverse to the bore 38 and the passage 40. The lower ends of the bores 36 and 38 at the recess 34 are countersunk at 44 and 46, respectively.

Each sampler unit within the housing 12 is provided with a suction means or aspirator 48 as shown in Figs. l and 2. As shown in Fig. 4, each aspirator consists of a body 50 and a cap 52. yThe body 50 is provided with a longitudinal bore 54 having varying diameters throughout its length. At 'the upper end of the bore the diameter is larger in order to provide a chamber 556 the upper end of which is threaded at 58. Below the chamber 56 the bore 54 has the configuration ofI a Venturi tube having its minimum diameter at 60. The lowermost end of the bore 54 is threaded at 62 in order to receive a threaded fitting 64 by which the outlet pipe` 20 is connected. The cap 52 is provided with a longitudinal bore 66 of varying diameters having its upper end threaded at 68 for connection with an air-supply tube 70. As is shown in Fig. 4, the bore 66 is disposed along the axis of the bore 54 of the aspirator body. Midway of the cap 52 the exterior surface is threaded at 72 for the purpose of securing the cap to the body 50 at the thread 58. An annular gasket 73 is disposed between the cap and the body. The lower tip of the cap is provided with a nozzle 74 which passes through and slightly below the chamber 56 into the Venturi portion of the bore 54. A passage 76, formed in the body 50, opens into the chamber 56 above the end of the nozzle 74. The passage 76 is connected to the passage 42 in the member 26 by a short segment of p ipe or tubing 78 the ends of which are threaded for attachment purposes (Figs. 2, 5 and 6).

Referring to Figs. 2 and 3, several pipes are connected to the member 26. Nipples 79 and 80 are connected to opposite ends of the passage 40. The nipple 80 is attached to an elbow 82 which, in turn, is connected to a hand valve k84 having a handle 85 located outside the upper side of the housing 12 (Figs. 3 and 4). The valve 84 is connected to a pipe 86 which extends upwardly through the top of the housing 12 to a source of wash water (not shown). The nipple 79 is connected to the inlet tube 18 by conventional fittings.

lt was indicated above that the retainer nut 32 would be set forth in greater detail below. As shown in Figs. l and 3 the nut supports three vertical leaf springs 88 which are equally spaced from each other about the periphery of the nut and have their upper ends attached to the nut by screws 90. The lower end of each spring 88 is bent outwardly and inwardly in order to support an object therebetween. The nut 32 is attached to the member 26 by means of an internal thread on the nut which engages the lower threaded end 30 of the member 26. The nut is provided with a radially inwardly extending frange 92 which forms a central aperture 94. Between the ilange 92 and the lower surface of the member 26 is disposed a needle assembly 96 (Fig. 5 The asscmbly includes a circular element 98 having a diameter less than that of the countersunk recess 34 into which the element 98 iits. The element has off-center openings which receive two sleeves 100 and 102 which are secured to the element 98 in a fluid-tight manner such as welding. The sleeves 100 and 102 support the upper ends of a pair of tubes or tubular needles 104 and 106, respectively, which may be similar to hypodermic needles in size and structure. These tubes are secured to the element 98 by a suitable method such as shrink tting. ln addition the needle 106 is longer than the needle 104 so that the lower end of the needle 106 is about 1/16 inch lower than that of the needle 104. The lower end of each needle is sharpened to a point and is open for the passage of uids. In order to simplify the maintenance and replacement of the needles, the assembly 96 is detachably enclosed between the ange 92 of the nut 32 and the member 26. The upper end of each sleeve 100 and 102 is inserted, respectively, into the countersunk portions 46 and 44 of the passages 38 and 36. The shorter needle 104 is connected to the aspirator 48 Via the bore 38 and the pipe 78, and the longer needle 106 is connected to the inlet tube 18 via the bore 36 and the passage 40.

In order to retain` any samples removed from the source tank 14-ar-receptacle -108-is provided. -YAs'shown in Figs. 3 and 5, the receptacle comprises a base 110, an upright cylinder 112 attached to the base, and a detachable;cap.1114.which.is.= securedlto the..cylinder, preferablyqin a .threadedtconnection findicated atY 116. The center ofthe .cap.114 isfapertured at 118 and is in alignment with the aperture 94 in the nut 32. Within thereceptacle is a.glass.yial.120. .':The1base,: cylinder, and cap ofthe receptaclef 108 arevpreferably made of ,Lucite, a polymer ofmethyhmethacrylate.' Between the.1ower endof the vial-120 and the base v110 is a padding 122. The upper end tof the vial contacts a puncturable flexible seal 124 formed of a..suitable material such as rubber, whichY is yclampedgbetween'.the.capY and cylinder. The thickness of the-padding.122. isV sufficient to cause the vial 120 to, clamp z:the.;seal 124.. tightly against the cap 114. Because .-of the relative lightness? of the materials in the receptacle 108;;1he` leaf springs 88 will support the receptacle-as AshowngingFig. 3... When the receptacle 108 is brought to the supported .positionishown in Fig. 3, the needles 104 and 106 pass through the aperture 118 in the cap 114 andfpuncturethe seal 124. When removing the assembly from.the..position shown it is necessary merely to `apply enough Vforce'to the receptacle to lower it from between the springs 88 and continue lowering until the seal is pulled oif the needles.

QperazionA The valve 84 is closed, and air-under pressure is supplied through the tube :70 to the aspirator 4 8. The air passing at high velocity lthrough the nozzle 74 and the restricted portion of the passage 54 has a low pressure and creates a low pressurey within the chamber 56. The chamber 56 communicating with interior of the vial 120 through passage;76, pipe 78passages 42 and 38, and needle 104, a low pressure is created inthe interior of the vial 120,.which is lower than that in the space over the liquid 16y in the receptacle 14. Thus part of the liquid 16 is drawn through pipe 18, nipple 79, passages 40 and 36, and needlep106 .into the vial,120. With the continued operationofxthe aspirator the liquid accumulates in the.vial .until the topsurfaceof the liquid encounters the lowerA end. of the higher Vneedle 104. vThe liquid is then drawn through. the higher needle and into the associated passages; including.y theaspirator, until it is returned to the source tank 14 via Ythe outlet tube 20. Circulation continues inxthismanner for such time as a representative sample of the liquid source is contained in the vial 120. tained, becauseintroduction of the liquid at one level in the vial and withdrawal of the liquid at a higher level in the vial produce agitation of the liquid. The fact that the lower ends of the needles are at dilerent levels means that liquid is not withdrawn from the vial as soon as it is introduced therein. When adesired sample is obtained the aspirator is shut oii'. The liquid in the needle 104 and the passage 38 drains into the vial 120. Time is now taken to allow the liquid in the vial above the lower end of the needle 106 to siphon back to the source tank 14 via thepipe 18. lThis takes place, because the vial isat a .higherlevel than the level of the liquid 16 in the tank 14. The volume of the sample in the vial 120 is determined by the distance between the bottoni of the Vial and the lower end of the needle 106.

The vial is removed by lowering it from the needles 104 A more representative sample is obmaim'ng liquid is returned to the sampler by again forcing the needles 104 and 106 through the diaphragm 124.

The aspirator 48 is again turned on and the valve 84 is opened in order to permit a wash liquid to enter the vial through the needle 106, and the liquid to be sampled is gradually washed out of the vial and returned to the source tank 14 via the outlet pipe 20 until only a wash liquid remains in the vial. After the wash liquid is circulated through the system a suicient length of time in order to warrant a complete return of the liquid to be sampled to the wash tank, the valve is closed, the aspirator turned off, and the vial may be removed from the sampler. At this point the vial contains only the wash liquid which is disposable.

The front face of the housing 12 is apertured at 126 for easy access to the sampler units. A window panel 128 is placed over the face where it is retained by four hollow heated members 130 and 130a. Two of the members 130 are disposed adjacent the upper corners of the panel 4128 and two members 130a are centrally dis- The Amembers posed near the lower edge of the panel. are retained in the panel 128 by screws 131 which'are threaded into the'members. A lift 132 is provided centrally at the lower edge of the panel where it is retained by the two lower members 130a. By lifting and withdrawingthe-lowerlfmembers130a from contact with the lower edge of-the aperture 126, lthe panel 128 may be lowered vertically from the aperture until the upper members 130 come to rest upon said lower edge. The upper headed members 130, being adjacent the corners of the panel 128, extend over theside edges of the opening 126, so as to keep the panel 128 in position at the opening 126, whetherthe panel -is in the position of Fig. l or in the lowered position just described in whichfth'e upper headed members-130c ome to' rest on the lower edge of the 'opening 126.; I. Y

Since the foregoing sampler is intended -for use with liquids that are eitherpoisonous or only slightly radioactive the comparative; thickness 'of the housing and the receptacle shown is sufficient. f-ln -the event that the liquids to ybey sampled -are highly radioactive, it is apparent that the housing maybe constructed of relatively thick plates of materialwhich absorb radioactivity and Ithedreceptacle may be replaced by a removablev cask of ea f,

Many equivalent devices employing the teachings will readily be devised by persons skilled inthe art. Accordingly the present invention shall be deemed to be limited only by the appended claim;-

What is claimed is:

A combination comprising two pipes for withdrawing liquid from and returning liquid to a container holding liquid to be sampled, two tubes connected to the two pipes, and 'a Vsampling vessel enclosing open ends of the tubes and haying itsl basenear said open ends, the tube connected to the withdrawing pipe having its open end nearer thebase ofthe vessel than is the open end of the other tube, and means in communication with the 'returning pipe and the tube with the/higher open end for sucking liquid into the vessel through the withdrawing pipeand the tubeL with the loweropenend.

References Cited in the iileof this'pate'nt UNTTED STATES PATENTS Number Name Y Date i V1,325,991 King Dec. 23, 19 9 1,799,591 i Kiefer Apr. 7, 19 l 1,842,134 Waite Jan. y19, 19,3l2

2,531,953 i vSmith et al. ..v Nov. 28, 1 950

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