US2979956A - Fluid sampler - Google Patents

Description

April 18, 1961 F. H. WARREN 2,979,956

FLUID SAMPLER Filed Aug. 6, 1958 2 Sheets-Sheet 1 INVENTo-R. Ffn H Warren BYQMQM TIORNEYS April 18, 1961 Filed Aug. 6, 1958 F. H. WARREN FLUID SAMPLER 2 Sheets-Sheet 2 IN VEN TOR. Fred H. Warrcn BY (Qua/(9M ATI'OR NEYS FLUID SAMPLER Fred H. Warren, 327 Glendale Ave., Findlay, Ohio Filed Aug. 6, 1958, Ser. No. 753,558 Claims. (Cl. 73,-f-422) 'Ihis invention relates to apparatus for collecting and dispensing fluids and more particularly to apparatus for obtaining iluid samples, such as oil, from a stream of iluid.

Liquid sampling techniques in the oil industry have undergone vast improvements as the importance of obtaining accurate samples has become recognized. The gravity, sediment, and water content of a sample of oil United States "Patent-() determine the price to be obtained and inaccuracies inthe sample will result in an undue profit or loss. For a truly representative sample, it must be taken from a representative portion of the main body of oil and must be maintained under proper pressure to prevent the escape of the lighter ends of the oil.

Where samples are taken periodically, it is important that the chamber in which the samples are collected be adequately purged between successive samples, inv order to avoid contamination of the latter sample by the remnants of its predecessor. Although many improved samplers are on the marketvwhich have solved the problems discussed in the above paragraph, these samplers do not provide completely satisfactory means for purging the sampling chamber or may not purge the chamber at all. In some cases, an excessively large sample is taken, a first portion of which is used to purge the chamber and deliberately wasted or the chamber is purged by pumping oil continuously through it, in which case the pump of the sampling mechanism must be operated continuously. In either case, the purging oil must then be either wasted or pumped back into the line, which requires additional piping and equipment.

The present invention provides an improved sampler that eliminates the disadvantages found in prior samplers, including those disclosed in my prior patents, 2,692,502 and 2,836,978. The sampler of my first patent did not function Well with sluggish or very cold or viscous oil and also stored the oil under atmospheric pressure which enabled some of the lighter ends of lighter oils to escape by evaporation. The sampler of my `second patent 'overcame these dilllculties by causing a positive ejection of a sample into the sample can but still required that purging oil be pumped back into the oil line or wasted.

A sampler according to the present invention is particularly adapted for sampling oil in -a moving stream but is also suitable for sampling various other fluids. The new sampler has a collecting chamber located directly in the stream of fluid to be tested and has adequate purging means that operate without the necessity of pumping additional fluid for this purpose `and without the necessity of continuously pumping vlluid and veither wasting it or providing an Yadditional line for returning the purging fluid to the stream. The new sampler also pumps the oil sample under positive pressure into a sample container in easily adjusted quantities.

It is, therefore, a principal object of the invention to provide an improved lluid sampler.

It is another object of the invention to provide a fluid angler which has means far ,adequately nursing seal- 2,979,956 Patented Apr. 18, 1961 ICS 2 ple collecting chamber without requiring additional fluid 'for this purpose.

Other objects and advantages of the invention will be apparent from the following detailed description of a preferred embodiment and a modification thereof, reference being made to the accompanying drawings, in which-f- Fig. l is a View in elevation with parts broken away of a sampler according to the invention; Fig. 2 is a fragmentary view of a portion of the apparatus shown in Fig. l, showing a plunger, Valve, and linkage in an intermediate operating position; Fig. 3 is a fragmentary view of a portion of the apparatus shown in Fig. 1, showing the plunger, valve, and linkage in a still different position corresponding to one en'd of an operating stroke; and

Fig. 4 is a view in elevation with parts broken away of a `modified form of a sampler according to the invention.

Referring to the drawings, Fig. 1 shows a sampler N1,1. powered by drive means 12. The sampler 11 comprises a body 13 including a cylindrical member 14 and a heavy flange 15 for attachment to a pipe line. The heavy flange 15 is suitably attached to a mating flange 16 carried. by the pipe line and having a neck 17 extending laterally from the peripheral surface of appipe line section 18 which carries th'e stream of fluid, suchras oil, which is to be periodically sampled. The body of the sampler extends through the neck 17 into a position `well within the stream of iluid flowing in the pipe 18 so that a truly representative sample is taken 'from the main body o'f the stream and not from a portion close to the side or bottom of the pipe. y

A bore 19 is drilled in the main body member 14 to form a working barrel which carries a discharge plunger 20 which is also bored to receive a stem 21 terminating in a sample admitting valve 22 having a face 23 that seats against a beveled portion 24 of the main body member 14.

A sample discharge passage 25 is provided through the member 14 and the heavy ilange 15 to connect a counter? bored recess 26 with the bore 19 at a point near the valve seat 24. A hollow threaded member 27 having a port 28 is screwed into the recess 26 and a ball check valve 29 is urged against the lower end of the port 28 by a spring 30 which seats against a follower 31 screwed into the member 27, thus enabling the follower to'bfe turned in and out to vary the force exerted on the ball check valve 29 through the spring 30. The fluid pressure at which the check valve 29 will allow iluid to pass downwardly through the port 28 is determined by the force exerted on the ball by the spring 30, as regulated by the position of the follower 31, which position is se'- cured by a lock nut 32. A pipe 33 is attached to tlie follower 31 and is connected to a sample container (not shown). 'f

The outer portion of the member 14 has an enlarged counterbore 34 in which there is disposed a 'spring 35 bearing against a seating ring 36 and a flange 37 of the plunger 29. The stem 21 of the sample admitting valve extends through the flange 37 and is reciproeable separately from the plunger. For this purpose the stem may be threaded as -at 38 and screwed into a clevis 39 pivotally attached at 40 to a first link 41. The threaded portion 3-8 is also provided with a locknut 42 which secures the stern 21 in any given position with respect toy the clevis 39. The upper end of the first link 41 is pivoted to an end of a connecting link 43, the other end of which is pivoted to the midpoint of a second link 44. The upper end of the link 44 is pivotally held to a stationary member such as an ear 45 attached to the heavy flange 15 and the lower end of the link 44 is operatively connected to the plunger 20, and for this purpose is pro- :means of their linkages.

nordsee vided with a recess 46 which coacts with pins 47 radially extending from the flange 37 of the plunger 20.

The lower end of the rst link 41 is the power receiving end and is pivotally attached to a clevis 48, which is screwed to a threaded portion 49 of a piston rod 50 and is secured by means of a locknut 51. The pistonrod 50 has an adjustable stop 52, held in place by a locknut 53, which limits the distance the rod 50 can extend into a cylinder 54.

The cylinder 54 is pivotally supported in trunnions 55 and a yoke 56 which is attached to the heavy flange 15.

Driving uid is supplied to each end of the cylinder 54, on each side of a piston 57, through conduits 58 and 59 connected toa four-way valve 60. Fluid is supplied ,to the four-way valve 60 from a supply line 61 and uid is vented from the cylinder 54 and the valve 6G through a discharge line 62. The valve 60 is operated by a solenoid 63 actuated at regular intervals by a program timer or by a liquid volume meter which can be made to supply current to the solenoid 63 upon passage of a predetermined quantity of liquid or upon elapse :of a predetermined time period. Current will be sup- .pled to the solenoid 63 for several seconds during each period of operation to rst admit fluid to the rod end .of the cylinder 54 and then to the blind end of the cylinder when the solenoid 63 is de-energized. The piston 57 is thereby driven to the blind end of the cylinder 54 and then back to the rod end where it remains until ,the solenoid 63 is again energized.

In operation, with the sampler 11 and operating mechanism 12 in the position shown in Fig. 1, the solenoid 63 is energized, when a sample is desired, to open the valve 60 to the line 58. Fluid is then admitted to the rod end of the cylinder 54 to force the piston 48 toward .the blind end of the cylinder, moving the piston rod t) in the same direction. The lower end of the iirst link .41 is thereby pulled bythe rod S0 which moves the valve stem 21 and the plunger 20 in the same direction by The plunger 2i) and the valve 22 thereby move into and toward the member 14 together, thus establishing a sample collecting chamber in vthe working barrel between the end of the plunger 20 and the rear face of the valve head 22 (see Fig. 2). This .collecting chamber remains in open communication with the pipe 18 until the plunger 20 reaches the end of its lstroke at the position shown in Fig. 2. This occurs when the face 23 of the valve 22 seats against the valve seat 24, thus forming an enclosed chamber filled with fluid. The valve stem 21 can no longer move toward the member 14 and the pivot point 4t) then becomes xed. As the piston rod 50 moves further toward the blind end of the cylinder 54, the rst link 41 rotates around the pivot 40 with the lower end moving toward the cylinder 54 with the piston rod 50, and the upper end moving in the opposite direction. This moves the lower end of the second link 44 toward the member 14. The link 44 thus causes the pin 47, the ange 37, and the plunger 20 to reverse its initial movement in the working barrel and to move toward the valve 22 to decrease the size of the collecting chamber formed in the bore 19. This forces uid in the chamber to flow through the passage 25, past the ball check valve 29 and into the sample container. The pressure exerted on the fluid is entirely independent of the pressure of the stream in the pipe 1S and thus the pressure in the sample container can be maintained either above or below the pressure of the stream at the selection of the operator.

As shown in Fig. 3 the rod 41 reaches the end of its stroke when the stop 52 abuts the rod end of the cylinder 54 and this determines the extent to which the plunger 20 moves back toward the valve 22 when closed and, hence, determines the amount of uid that is forced into the passage 25. This enables the size of the sample to be varied over a wide range simply by adjusting the stop nut 52. Once this adjustment is made, however,

4 l all samples taken will be of completely uniform volume since the parts that enter into the variation of sample size are mechanically positioned.

After completion of this inward stroke, the piston 57 Will remain at rest only until the solenoid 63 is de-energized and the valve 60 again directs fluid to the bhnd end of the cylinder 54 and moves the piston 57 toward the rod end. The valve 22 and the plunger 2G will then be moved toward their initial position in which they stand between rthe taking-of samples and in'which the valve 22 is opened andthe plunger 20 has filled the bore of the working barrel. `Movement of the plunger 2t] in this direction will expel any fluid remaining in the collecting chamber formed in the bore 19. When the llange 37 abuts the flange 15, the second link 44 is held in a fixed position because both of its ends are now lixed. The intermediate'pivot of the link 44 thereby is xed and the links 41 and 42 move about this pivot and further extend the valve 22v until the rod 50 has completed its stroke away from the cylinder 54. The parts remain 1n this position between cycles.

It will be readily apparent that after the valve 22 is seated and the plunger 20 has forced fluid in the collecting chamber through vthe passage 25, any remaining iluid in the chamber is expelled upon the return stroke of the piston 57 to the rod end of the cylinder 54, which moves ushed by the moving stream of fluid in the pipe 18.

Thus, no lluid from a prior sample can contaminate a subsequent sample because of the action of the plunger 20 and the flushing action of the moving stream of fluid.

This overcomes the contamination problem without the Yusual necessity of pumping additional uid through the chamber as is true for the known devices in which the sample or collecting chamber is located remotely from a pipe which carries the uid to be tested. Further, with the new sampler, the sample is taken immediately from the pipe and is known to be a true sample at that moment because there are no long intervening passages or conduits between the sample chamber and the pipe which can contain uid from a prior portion of the stream flowing through the pipe. In the drawings, the size of passage 25 is exaggerated to show it clearly. In practice this passage can be made small and thus of very limited capacity.

Fig. 4I shows the sampler mechanism 11 driven by a modified operating mechanism 64, which includes a motor 65 operated at intervals by means of a program timer or by a liquid volume meter, as previously discussed, which controls the ow of current or hydraulic iluid through a line 66. When the motor 65 is actuated, it drivesv a shaft 67 through one complete revolution at which time the motor 65 will be stopped, for example, by means of a limit switch, and the motor will then remain at rest until again actuated. The shaft 67 has a cam 68 affixed thereto which rotates with the shaft 67 and reciprocat'es a pitman 69. A rod 71 is carried in a bore 72 of the pitman 69 and has a lost motion connection therewith. The rod is held against the pitman by a stop 73 which is urged against the end of the pitman 69 by a spring 74. The spring 74 is located between washers 75 and 76, the latter being held by a nut 77 and a locknut 78 and serves to permit a separating motion of the stop 73 and the adjacent face of the pitman as hereinafter described. The rod 71 is pivotally attached by a clevis 79 to a link 80, which is similar to the rst link 41 of Figs. 1-3 except for an extended lower arm portion 851. Rearward movement of the link 80 and the arm portion 81 is adjustably limited by means of a threaded stop 82 held with the aid of a locknut 83 in a support 84. The stop 82 enables variation n the size of the sample taken in the same manner as the stop 52, as previously discussed. The support 84 may be located on a platform 85 which also serves to locate and support the sampler 11 and the operating mechanism 64.

The sampler 11 in Fig. 4 is shown in an inactive position, ready to take a sample. As the shaft 67 rotates in either direction, it causes the rod 71 to retract and thereby retract the plunger 20 and the valve 22 in the same manner as with the previous embodiment. After the valve 22 seats on the beveled portion 24 of the body 14, the pivot point 40 becomes iixed and further retraction of the rod 71 forces the plunger back toward the valve 22, thus forcing liquid in the void to liow into the passage 25. This action occurs until the lower end81 of the link 80 abuts the stop 82, at which` time no further movement of any parts of the sampler occurs until the rod 71 again moves away from the motor 65. After the portion 81 ofthe link 80 hits the stop 82, further rotation of the shaft 67 merely serves to compress the spring 74 until the shaft has been rotated 180, after which the lost motion connection between the pitman 69 and rod 71 will be taken up and the rod will move the valve Z2 and the plunger 20 towards the initial position in which the reopened valve extends into the pipe 18, and the plunger acts to expel any remaining liquid in the collecting chamber. The parts of the sampler are ready to take another sample when the shaft 67 has completed one revolution.

Various modifications of the invention will be suggested from the above description and accompanying drawings and it is understood that such modifications may be made without departing from the invention as dened in the accompanying claims.

What I claim is:

1. A sampler for taking successive samples from a stream of moving iluid, said sampler comprising a hollow member extending into a stream of uid to be sampled, a plunger slidably carried in said member, a valve at the end of said member extending into the stream for opening the hollow member to the stream and for closing off the hollow member from the stream, means forming a passage outside the hollow member, an end of which passage communicates with the hollow member near the valve for connecting the hollow member with a sample container or the like, and means for closing the valve and retracting the plunger to draw uid into the member until the valve is closed and for extending the plunger toward said valve while the valve remains closed to expel at least part of said fluid through said passage.

2. A sampler for taking successive, discontinuous samples from a stream of moving uid, said sampler comprising a hollow member extending into a stream of uid to be sampled, a plunger slidably carried in said member, a valve stem extending through the plunger, a valve attached to the stem, means forming a passage outside the member, an end of which passage communicates with the hollow member near the end of the member extending into the stream for connecting the member with a sample container or the like, and means for positioning said plunger to substantially fill the hollow member when the valve is spaced from the end of said member and for retracting said plunger and said valve until the valve seats on the inner end of said member to form a collecting chamber in said hollow member, and draw iluid thereinto, and means to move said plunger into said collecting chamber while said valve remains closed and thereby expel fluid from said chamber through said passage.

3. Apparatus according to claim 2 and means for lineally varying the distance said plunger extends toward said valve, when closed.

4. A sampler for obtaining a sample from a stream of uid, said sampler comprising a hollow member extending into a stream of luid to be sampled, a plunger slidably carried in said member, a valve stem extending through said plunger, a valve attached to said stem, means forming a passage outside said hollow member, an end of which passage communicates with said hollow member near the end of said member extending into the stream for connecting said member with a sample container or the like, a rod, means for reciprocating said rod, and linking means connecting said rod to said plunger and said valve stem to cause said plunger to substantially lill said hollow body and said valve to be spaced from the inner end of said body when said rod is at one end of a stroke, to retract said plunger and said valve until said valve seats against said end of said member, and for extending said plunger when said valve is closed until said rod reaches the other end of a single stroke.

5. A sampler for taking successive samples from a stream of fluid, said sampler comprising wall means forming a chamber substantially wholly located within the stream, a valve means at one end of the chamber, means forming a passage outside said chamber, one end of which passage communicates with said chamber near said valve means and extends away from the stream for connecting said chamber with a sample container or the like, a plunger at the other end of the chamber, means for moving said plunger to trap liquid from the stream in said chamber, and means for moving one of said plunger and valve means toward the other to expel the liquid trapped in said chamber into said passage.

References Cited in the le of this patent UNITED STATES PATENTS 2,205,875 Colley et al.` June 25, 1940 2,794,344 Boren June 4, 1957 2,836,978 Warren June 3, 1958 2,872,817 Pitts Feb. 10, 1959

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