WO2004045960A2

WO2004045960A2 - Lever actuated closed loop constant volume sampler system

Info

Publication number: WO2004045960A2
Application number: PCT/US2003/036583
Authority: WO
Inventors: Jay Seligman; David J. Anderson
Original assignee: Texas Sampling, Inc.
Priority date: 2002-11-15
Filing date: 2003-11-14
Publication date: 2004-06-03
Also published as: AU2003290963A8; WO2004045960A3; AU2003290963A1

Abstract

This invention relates to a lever actuated sampling system (10) for collecting a constant volume sample in a septum closed container (11). More particularly, this system provides a manual lever (18) and a reservoir (14A) with a predetermined volume which, upon manual lever activation of valves (13, 15) on the inlet and outlet of the reservoir (14A), reliably captures and provides for routing of the captured sample from the reservoir (14A) into the septum closed container (11).

Description

LENER ACTUATED CLOSED LOOP CONSTANT VOLUME SAMPLER

SYSTEM

This invention relates to a lever actuated sampling system for collecting a constant volume sample in a septum-closed container. More particularly, this system provides a reservoir of a predetermined volume which, upon manual lever actuation of valves on the inlet and outlet of the reservoir, reliably captures a sample and provides for routing of the captured sample from the reservoir to the septum closed container.

In the operation of many chemical and other processes, it is often necessary to periodically sample process fluids that are flowing within the process at various points. For a variety of reasons, it is often advantageous and even necessary to collect the fluid in a septum closed container, e.g., the sample is volatile, the fluid presents a safety hazard if released to the atmosphere, or the sample may be sensitive to absorption of air or atmospheric moisture. Various designs of septum closed containers and samplers are known. Examples of such septum closed containers and samplers are shown in U.S. Pat. Nos. 4,174,632 and 4,887,472 to Jansen and U.S. Pat. Nos. 4,651,574, 4,791,821, 4,879,915 and 4,986,138 to Spencer. Improved septum closed containers and samplers are shown in U.S. Pat. Nos. 5,301,506 and 5,431,067.

The systems for collecting a constant volume sample with several of the heretofore known septum closed containers and samplers present several disadvantages. First, heretofore known samplers and associated systems for collecting a constant volume sample in a closed loop system may contain a "dead volume" i.e., a configuration which allows fluid from a previous sample to occupy a part of the system or sampler and to contaminate a later sample, leading to inaccurate analysis. In addition, several heretofore known systems for the collection of a sample typically require the independent operation of several valves. This may lead to error in collecting a representative and consistent sample and is time consuming, as it requires special procedures. For instance, the technician (person catching sample) must allow fluid to flow through the sample line adjacent the septum closed container, then, he must open the valve to the septum closed container which again presents several disadvantages. Here, a technician must attempt to fill the septum-closed container by opening and closing its inlet valve. This leads to a sample which is not of a consistent volume with previous samples, which may make it difficult for laboratory personnel to effectively manage the samples of varying volume. In addition, the technician may have a difficult time in filling the septum closed container without overfilling the container. This is especially a problem with small sample containers. Further, in catching a sample in this manner, the septum-closed container is usually subjected to process pressure. If process pressure is unexpectedly high, it may cause the overpressuring and subsequent rupture of the septum-closed container. This presents a significant safety hazard in that the person catching the sample may be subjected to harmful vapors or fragmented glass or metal portions of the septum closed container.

U.S. Pat. No. 4,987,785 to Spencer discloses a sampling system that provides for constant volume sampling which includes a section of tubing having a predetermined volume with three-way valves on the ends of the tubing. This system provides for the simultaneous operation of the two three-way valves. While this Spencer patent addresses several of the disadvantages presented above, it has several shortcomings that significantly limit its usefulness. First, this patent discloses a chain and sprocket system for simultaneous movement of the two three-way valves. This chain and sprocket system would not reliably function effectively in a chemical plant or refinery environment because the chain and sprocket system would need constant adjustment and maintenance to ensure that the valves are moved simultaneously. In addition, this chain and sprocket system could easily "freeze-up" due to the corrosive nature of these plant environments. Thus, this chain and sprocket valve actuating mechanism would not be viewed as reliable by personnel operating a chemical plant or refinery. Also, the configuration of the Spencer sample system would allow sample fluid to leak into the pressurized gas line used for transferring the sample fluid from the reservoir tubing to the sample container and lead to contamination of the next sample or varying sample volumes. Further, this Spencer system does not provide for ease of operation, i.e., it does not provide the person catching the sample with assurance that the system is functioning properly. Still further, this system does not provide adequate safeguards against equipment or system failures that are required in a chemical plant or refinery environment. U.S. Patent 5,433,120 to Boyd provides a significant improvement to a constant volume sampling system such as Spencer. In the constant volume sampling system of Boyd U.S. Patent 5,433,120 the chain and sprocket valve actuation means of Spencer U.S. Pat. No. 4,987,785 is supplanted by a dual-action pneumatic actuator means for effectuating the catching of a constant volume sample.

Albeit that Boyd U.S. Patent 5,433,120 represents a significant advance over the constant volume closed loop sampling system of Spencer U.S. Pat. No. 4,987,785 in terms of reliability of the constant volume sampling system, it resolves the Spencer problem by a more complex, although a more reliable, mechanism than that of Spencer. In this aspect there still exist in this art a desire for a constant volume sampling system the sample catching mechanism of which is simpler of operation, "dead man" and fool proof, and, if possible, less expensive.

There exists a need for a simplified sampling system for collecting a sample by a closed loop system in a septum closed container which prevents contamination of a sample by fluid from an earlier sample contained in a dead volume, provides a consistent size sample, allows collection of a sample upon the manual operation of a single lever and is also safe to operate in that the sample container is not subjected to process pressure and which allows samples to be obtained without overfilling the septum closed container.

This invention relates to a sampling system for close loop collection of a sample in a septum-closed container. The system includes a reservoir having a predetermined volume and an inlet and outlet, the inlet and outlet having specially modified three-way ball valves. The three-way ball valves have a specialized porting of the valve ball that allows for actuating the three-way valves by only 90° to change the flow through the valves so as to capture a sample in the reservoir. This specialized porting of the valve ball allows for the dual activation of these valves in unison by a single manually operated lever that is spring biased for return to its process flow through non sampling position. In addition, the system includes means for positively diverting a captured sample from the reservoir to the septum closed container.

^"With the present invention, the fluid to be sampled normally flows through the reservoir. When it is desired to obtain a sample, a technician activates a single lever by 90° which in turn actuates in unison the three-way valves to first temporarily contain a sample within the reservoir and then provides for the routing and pressuring of the sample contained in the reservoir from the reservoir to the septum closed container. Further, the pressurized gas purges the system and sampler to remove fluid from any dead volume to ensure that a later sample is not contaminated by fluid from an earlier sample.

The present invention requires a technician to operate but a single lever that effects the actuation in unison of the three-way valves. The sample is automatically captured in the reservoir and then diverted to the septum closed container. This provides for several advantages including a consistent sized sample, easy operation, the avoidance of subjecting the septum closed container to process pressure, and the avoidance of overfilling the septum closed container and the automatic return of the sampling valves to their by-pass position upon release of the lever by the technician.

A better understanding of the present invention can be obtained when the detailed description of exemplary embodiments set forth below is considered in conjunction with the attached drawings, in which:

Figure 1 is a process flow diagram showing an embodiment of the system wherein one lever mechanism (illustrated in Fig. 4) operates both three-way valves.

Figure 2 view A is a sectional view of the valve ball 13' of sample capture valve 13 of Figure 1 and view B is a sectional view of the valve ball 15' of vent valve 15 of Figure 1 and the special modified ports of valve balls 13' and 15' which allows for 90° rotation of the valve balls, as shown in Figure 3 views A and B, to effectuate capture of a sample. In Figure 2 the valve balls are portrayed in the by-pass position.

Figure 3 portrays the valve balls 13' and 15' after 90° rotation of the valve balls to their sample capture position to effectuate capture of a sample.

Figure 4, view A as a front view and view B as a side view, is an illustration of the single lever mechanism by which the capture of a sample is effectuated.

The present invention relates to a sampling system for the closed loop collection of a sample in a septum closed container. While this system allows for the collection of a sample in many varieties of septum closed containers, the preferred septum closed container has a has the needle which passes through the septum, means for venting and purging the sample container and means for holding the sample container as are disclosed in commonly owned U.S. Pat. No. 5,301,560 and U.S. Pat. No. 5,431,067, hereby incorporated by reference.

FIG. 1 shows one embodiment of a system 10 for collecting a sample in a septum closed container 11. The septum closed container and its associated holding means are preferably of a structure as described in U.S. Pat. No. 5,301,560 and U.S. Pat. No. 5,431,067, hence for further description of the details thereof reference may be made to these patents. Under normal operation, i.e., when a sample is not being caught, i.e., the process fluid is on by-pass flow relative to the septum closed container, that is, the fluid flows through sample inlet line 12 and into valve port 13a of three-way valve 13. As discussed in more detail below, valve 13 is preferably a three-way ball valve having an "T" ported valve body which, in its conventional configuration with an "L" ported valve ball, allows for fluid communication between valve port 13a and valve port 13b or between port valve 13b and valve port 13c as desired. Valve port 13b is the common port, that is, the port in the valve ball 13'b remains in constant registry with valve port 13b. Rotation of the valve ball about the axis of valve port 13b brings the other port of the "L" ported valve ball into or out of registry with valve ports 13a and 13c. The fluid flows from valve port 13a, through valve 13 to valve port 13b, entering line 14. Line 14 combined with sample cylinder 14a, if required, constitutes the constant size "reservoir." The fluid flow continues through line 14 where it passes through valve port 15a and valve port 15b of three-way valve 15. Here, valve 15 is preferably a three- way ball valve having an "T" ported valve body similar in design to valve 13 and modified to have a special porting carried by its valve ball as is valve 13, as hereinafter discussed. The fluid exits sample outlet line 16 and is returned to the process. Normally, the fluid flows in the above-described path on an ongoing basis. The closed loop constant volume sampling system, including piping, valves, etc., is configured to avoid any "dead volume" or "pockets", thus ensuring that the sample taken is representative of the fluid in the process stream at the moment of sampling. Here, inlet line 12 is connected to the process stream at a location providing a higher pressure than where sample outlet line 16 is connected to the process, this so as to maintain the flow described above. For example, it is commonly known to provide a sample line from the discharge of a pump to the suction of the pump or from upstream of a control valve to downstream of the control valve. This ensures that a representative sample is continually flowing through the sample line.

To accomplish this by-pass flow characteristic of the system, i.e., process flow from line 12 through valve port 13a out through valve port 13b into line 14, sample cylinder 14a to valve port 15a and from there through valve port 15b for return to the process by outlet line 16, the conventional valve bodies and valve body ports of valves 13 and 15 are utilized. However, to provide for capture of a sample in septum closed container 11 via a 90° operation of lever 18, the balls of valves 13 and 15 are specially modified. Commercially available 3 -way ball valves configured for 180° activation between fluid flow operative positions have a "T" ported valve body and an "L" ported valve ball. In such commercial 3 -way ball valves the ball ports are of a diameter which is about 70- 75% of the diameter of the valve body ports. In such valves, during the 180° rotation of the valve ball between its first fluid operative position to its second fluid operative position the non-common port of the valve ball is totally seated - hence totally closed to fluid flow - through about a dwell of about 50°. As will be discussed, lever 18 is spring biased to be retained and/or returned to that position whereby process fluid flow by-passes a capture by the septum closed container 11, such by-pass flow is as described above. With a conventional three-way valve having an "T" port arrangement it would be necessary to operate the valve balls thereof through 180° of rotation to close the by-pass loop to process fluid flow and divert fluid trapped in this loop into septum closed container 11. Since this could make lever 18 difficult to fully operate against the spring tension needed to biased lever 18 to a return to its normal by-pass. position, preferably the ball of each of valve 13 and 15 is modified as shown in Figs. 2 and 3.

Fig. 2 views A and B respectively illustrate, in a cross sectional view, the ball 13' of the sample capture three-way ball valve 13 and the ball 15' of vent valve 15 as theses balls are in a by-pass position. For ease of illustration the valve housing and valve ball actuator are not shown. Valve ball port 13'b is continuously in communication with valve port 13b (and line 14 per Fig. 1) irrespective of the rotation of the valve ball. As illustrated in view A, valve ball port 13'a is in communication with valve port 13a (and line 12 per Fig. 1), however it will be realized that a 180° rotation of the valve ball will bring ball port 13 'a into communication with valve port 13c (and the line that feeds septum closed container 11 per Fig.l). The line of view of ball 13' is down the axis of ball port 13'b looking towards valve port 13b which is behind ball port 13'b. In Figure 2 view B valve ball port 15 'a is continuously in communication with valve port 15a (and line 14 per Fig. 1) irrespective of the rotation of the valve ball. Valve ball port 15'b is in communication with valve port 15b (and line 16 per Fig. 1), however it will be realized that a 180° rotation of the valve ball will bring ball port 15'b into communication with valve port 15c (and line 19 through check valve 30 per Fig.l). The line of view of ball 15' is down the axis of ball port 15 'a looking from valve port 15a which is in front of ball port 15'a towards ball port 15'a.

In this respect, as concerns a preferred embodiment of this invention, the ball of the sample capture valve 13 is modified with respect to valve ball port 13'a and a new ball port 13'd is established in the ball. Each of ball ports 13 'a and 13'd intersect ball port 13'b at a 90° angle to communicate with ball port 13'b. Whereas ball port 13'b may be a convention circular cross section configuration and its diameter is about 70 - 75% of the diameter of the valve body port to which it is common, ball port 13 'a is of a smaller dimension across the line about which it rotates, hereafter referred to as its "effective diameter," and preferable is of an oblong or rectangular cross section shape, and new ball port 13'd is also of a smaller dimension and may be of a circular cross section configuration. Since ball port 13 'a passes the fluid being sampled to ball port 13'b, so as to not unduly restrict fluid flow as ball port 13 'a is in full registry with body port 13a, it is preferred that the cross section area of ball port 13'a be at least about 80% of that of ball port 13'b. Hence, for example by reference to a typical " 2 inch three way ball valve" (the conduits which communicate with the valve are ^lA inch outside diameter) wherein the ball is of 0.9375 inch diameter and the valve body ports are of 0.5775 inch diameter, the common ball port 13'b would be of a diameter of about 0.421 inch. In this context ball port 13'a could be formed of a rectangular cross section with an effective diameter of 0.25 inch and a length of 0.50 inch, in which case its cross section area would be 0.25 x 0.50 = 0.125, which is about 90% of the cross sectional area of common ball port 13'b. Ball port 13'd may be of like dimensions and circular without concern for restricting fluid flow since port 13'd, when in its sample capture position, feeds a line that feeds to a needle of even a smaller cross section area.

The angles between the center lines of ball ports 13'a and 13'd will depend upon their effective diameters. Small effective diameters for 13'a and 13'd allow for a wider range of angles whereas larger effective diameters allow for a lesser range of angles. Hence, for example, wherein the effective diameter of ball ports 13'a and 13'd is 50% of that of common port 13'b, the angle between the centerlines of ball ports 13'a and 13'd may range between 40 to 78°, with the 40° separation providing for totally closed ports through a dwell of 28° while being switched from by-pass to sample capture mode. Wherein ball ports 13'a and 13'd are 80% of the diameter of common port 13'b, then the angle between 13'a 13'd may range only between 56- 62,° with the 56° separation providing for totally closed ports through a dwell of 6° while being switched from by-pass to sample capture mode. Surrounding the valve ball, as defined by the valve housing of valve 13, is a valve seat that closes the ball port 13'a to fluid communication except as ball port 13'a comes into registry with valve port 13a and in communication with line 12 or valve port 13c and the line that feeds septum closed container 11. Hence, as illustrated in view A of Figure 3, at 90° rotation of the valve ball, ball port 13'a would be sealed against the valve seat and would not be open to fluid flow. Special valve ball port 13'd is preferably established in a location relative to ball port 13'a such that port 13'd only begins to come into registry with valve port 13c and a line that feeds septum closed container 11 only when ball port 13'a is totally closed to fluid communication by registration to the valve seat of valve 13. The angle between ball ports 13'a and 13'd to ensure total closure of ball port 13'a to fluid flow when ball port 13'd begins to come into registry with valve port 13c is such that the leading edge of ball port 13'd and the trailing edge of ball port 13'a will be encompassed by the valve seat during at least 1° of rotation of the valve ball between the operative positions of the valve 13.

In like manner to valve 13, the ball 15' of vent valve 15, as illustrated by Figure 2 view B, is preferably modified with respect to valve ball port 15'b and a new ball port 15'd is established in the ball. Each of ball ports 15'b and 15'd intersect ball port 15'a at a 90° angle relative to the centerlines of the ball ports and communicate with ball port 15'a. Whereas ball port 15'a may be a convention circular cross section configuration and its diameter is about 70 - 75% of the diameter of the valve body port to which it is common, ball port 15'b is of a smaller dimension across the line about which it rotates, hereafter referred to as its "effective diameter," and preferable is of an oblong or rectangular cross section, and new ball port 15'd is also of a smaller dimension and may be of a circular cross section configuration. Valve port 15a is the common port, i.e. the port 15'a in the valve ball 15' remains in constant registry with valve port 15a. Rotation of the valve ball about the axis of valve port 15a brings the other port of the valve ball 15' into or out of registry with valve ports 15b and 15c. Surrounding the valve ball, as defined by the valve housing of valve 15, is a valve seat that closes the ball port 15'b to fluid communication except as ball port 15'b comes into registry with valve port 15b and in communication with line 16. Hence, at 90° rotation of the valve ball 15' of valve 15 ball port 15'b would be sealed against the valve seat and would not be open to fluid flow. Special ball port 15'd is preferably located relative to ball port 15'b such that ball port 15'd only begins to come into registry with valve port 15c and line 19 only when ball port 15'b is totally closed by registration to the valve seat of valve 15. The angle between ball ports 15'b and 15'd to ensure total closure of ball port 15'b to fluid flow when ball port 15'd begins to come into registry with valve port 15c is such that the leading edge of ball port 15'd and the trailing edge of ball port 15'b will be encompassed by the valve seat during at least 1° of rotation of the valve ball between the operative positions of the valve 15. As before discussed with reference to valve ball 13' the angles between the center lines of ball ports 15'b and 15'd will depend upon their effective diameters. In the case of vent valve 15 ball port 15'd, when in the sample capture position, passes only pressurized gas hence its effective diameter may be much smaller and the angle between it and port 15'b may be greater.

With reference to a ^XA inch three way ball valve, as an example, the ball 13' of the sample valve 13 would preferable have ball ports 13'a and 13'd that relative to their center lines are angled at about 50° to each other and in the by-pass position ball port 13'a would be relative to the center lines of valve port 13a angled at 16°. That is, from the center line of valve port 13a and with reference to the direction of rotation of the ball the center line of ball port 13'a is at a 16° angle and the center line of ball port 13'd is at a 66° angle. The effective diameter of each of ball ports 13'a and 13'd is about 0.25 inch. In this example the ball 15' of vent valve would preferable have ball ports 15'b and 15'd that relative to their center lines are angled at about 65° to each other and in the by-pass position ball port 15'b would be relative to the center lines of valve port 15b angled at 19°. That is, from the center line of valve port 15b and with reference to the direction of rotation of the ball the center line of ball port 15'b is at a 19° angle and the center line of ball port 15'd is at a 77° angle. The effective diameter of ball port 15'b is about 0.30 inch whereas the effective diameter of ball port 15'd is about 0.2 inch. In this example from the by-pass position of 0° of ball rotation, 38° of rotation of both balls simultaneously will just close process flow through both of valves 13 and 15, all ball ports remain closed through another 8° of rotation (total rotation to this point is 46°), through another 15° of rotation ball port 15'd of vent valve begins to come into registry with valve port 15c while flow through valve 13 remains closed (total rotation to this point is 61°), and during the final 29° of rotation ball port 13'd of sample valve comes into registry with valve port 13a to allow capture of the sample from the reservoir as motivated by pressurized gas admitted through port 15'd of the ball of the vent valve 15 (total rotation to this point is 90°).

The special porting established in the valve balls of valves 13 and 15 thus allows lever 18 to manually operate the valves for sample capture by a rotation of only 90°. Figure 4 illustrates the spring returnable lever actuator unit by which valves 13 and 15 are simultaneously actuated for the capture of a constant volume sample in septum closed container 11. The lever actuator unit comprises a housing 20, which carries spring retainer 22. The unit is provided with a lever arm 18d one end of which is securely affixed to a shaft 18a and the other end of which is affixed with a handle or knob 18c. Shaft 18a is carried by and secured with openings 21 in housing 20 such that shaft 18a is rotateable therein and each end 18e of shaft 18a extends beyond the housing limits and are free to be operatively connected to the ball valve actuator stems 13s andl5s of valves 13 and 15. Spring 18b is a spiral wound spring composed of spring steel each end of which carries a tab. One end tab 24 of spring 18b is positioned within a slot 25 cut into shaft 18a and secured therein by a retaining cover 25a that is secured to steml 8a by any securing means, such as screws 25b. The other end 26 of spring 18b, after spring 18b is brought into a state of spring tension sufficient to insure a return of lever arm 18b to that position wherein process fluid flow is on a by-pass flow as to septum closed container 11, is affixed against and retained by spring retainer 22. Movement of lever arm 18b is limited to 90° by suitable stop limits, such as the top and bottom walls of the housing 20.

When a sample is desired, a technician need only place the septum closed container and its respective holder and activate lever arm 18d. The activation of lever arm 18d rotates shaft 18a, which activates the two three-way valves 13 and 15 as described below. Preferably, actuator 18 is a 0°-90° actuator. Actuation of lever arm 18d turns shaft 18a through a rotation of 90°. This rotation of shaft 18a in turn rotates by 90° the balls in three-way valve 13 and three-way valve 15. This rotation of the balls in valve 13 and valve 15 momentarily captures the fluid contained in line 14 and sample cylinder 14a and isolates it from the fluid in inlet line 12 and outlet line 16. This manipulation of valve 13 aligns ball port 13'd with valve port 13c and line 11a such that fluid may flow from line 14 and sample cylinder 14a into the septum closed container 11. Manipulation of valve 15 aligns ball port 15'd with valve port 15c and line 19 such that a pressurized gas may flow through line 19, into ball port 15'd, out ball port 15'a, out valve port 15a and pressure the sample contained in the reservoir, i.e., line 14 and sample cylinder 14a, from the reservoir into the septum closed container 11.

Returning to Figure 1, as seen, line 14 and sample cylinder 14a provide a reservoir of constant volume. Here, the volume is predetermined as desired to correspond with the volume of the sample container 11 and meet other considerations such as the requirements of laboratory testing equipment. It is seen that the simultaneous manipulation of valve 13 and valve 15 momentarily captures the fluid to be sampled in the reservoir, line 14 and sample cylinder 14a, and then this captured sample is diverted to the septum closed container 11 and, in fact, is pressured into the septum closed container 11 by the pressurized gas in line 19. The pressurized gas further serves to purge all fluid from the reservoir and the sampler, including the needle, such that these components are cleared of all fluid to avoid the contamination of a later sample. This pressurized gas is vented from the septum-closed container 11 via a vent passageway to line 27 to prevent overpressuring the septum-closed container 11.

Preferably, the outlet of the sample cylinder 14a includes an interior conical-shaped section 14b on the outlet of the sample cylinder 14a to the septum closed container 11, such that when the sample is pressured into the septum closed container 11, the liquid is funneled from the cylinder 14a into the container 11 such that no liquid is left in the cylinder 14a. This conical-shaped section 14b prevents the pressurized gas from blowing through the cylinder 14a, and leaving sample material in the cylinder 14a, which may contaminate the next sample taken.

After the sample has been obtained in the septum-closed container 11, the activation lever arm 18d is returned to its presampling position. As described below, this actuates shaft 18a such that valve 13 and valve 15 are returned to their presampling by-pass position, allowing the fluid to flow through the "sample line", consisting of flow through inlet line 12, through port 13 a, exiting valve 13 through port 13 b, through line 14, through sampler cylinder 14a, continuing through line 14 and exiting through valve 15 and sample outlet line 16. This allows the fluid to flow through the sample line such that the sample line will contain a representative sample for the next sample to be taken.

The present inventive system is designed for ease of operation in obtaining a sample and also to provide a fail safe/fail closed "dead man's" handle acturator. First, to catch a sample one only needs to operate one lever, i.e., activation lever arm 18d. This captures the predetermined volume of the sample in the reservoir and automatically diverts this captured sample into the septum-closed container 11. In addition, a flow indicator, e.g., a rotameter 23 may be installed in a pressurized gas stream to assure the technician that the pressurized gas is flowing and that the system is operating correctly. Further, the technician can see the septum closed container filling and is thus assured that the system is operating correctly.

System 10 of Figure 1 contains a continuous purge through line 26 and rotameter 23. Here, the technician may observe rotameter 23 to assure himself that the pressurized gas is continually flowing and that the system is operating correctly. Here, the pressurized gas from line 26 serves to purge the septum closed container 11 of any air or moisture before the sample is taken and purges the fluid from the needle after the sample is taken. Purging in this manner is particularly applicable when a small sample is to be obtained.

In addition, the system provides for the advantage of consistent size samples. Here, it is preferred that the field technicians, i.e., the operators of the process equipment, work with the laboratory or testing services personnel to determine the specific needs or desires for the size of the sample container and the volume of the sample caught. The laboratory or testing services personnel should consider the equipment that analyzes the sample. For example, an automated gas chromatograph may be designed for operation with a certain sized sample container filled with a certain volume of sample. Here, the inventive sampling system would be designed to fill that container to the predetermined volume such that the same sample container may be used to catch the sample and to automatically analyze the sample in the laboratory. This avoids the errors associated with transferring the sample from one sample container to another sample container for analysis and also requires less manpower.

The inventive sampling system further has the advantage of using the pressurized gas stream, preferably nitrogen from line 19, to push the sample into the sample container 11 rather than relying on process pressure. As shown in Figure 1, a back pressure regulator 25 controls the pressure of the pressurized gas in lines 19. Here, the pressure regulator 25 controls the pressure of the gas stream that pushes the captured sample from the reservoir to the septum closed container 11. Preferably, the back pressure regulator 25 would be set at approximately 5 to 10 psig and the pressurized gas would be nitrogen. This 5 to 10 psig of pressure is sufficient to push the sample from the reservoir to the septum-closed container 11 while ensuring that the septum closed container is not overpressured. Any excess pressurized gas that flows into the septum- closed container 11 is simply vented through vent line 27. Other sampling systems which rely on the process pressure to push the sample into the septum closed container may subject the septum closed container to much higher and unexpected pressure, thus overpressuring and rupturing the septum closed container and possibly injuring the technician due to the release of hazardous sample material or the shattering of the septum closed container.

Preferably, the pressurized gas to valve 15 is provided with a check valve 30, which prevents sample fluid from flowing or otherwise being collected in line 19. In addition, preferably line 19 and the check valve 30 are located vertically on top of valve 15 to further prevent sample fluid from moving into line 19. Without this check valve 30 and its position on the vertical top of valve 15, sample fluid may enter line 19 so as to vary the amount of sample collected in the septum closed container 11 or contaminate a sample with old sample fluid contained in line 19.

The Figure 1 embodiment provides for a purging of the needle by an inert gas, preferably nitrogen, entering through line 26. Purging in this manner accomplishes several functions. First, it provides a clean needle, empty of any sample material, such that the next sample taken will not be contaminated by previous sample material remaining in the needle from the previous sample. Also, purging removes any sample material from the needle that may act to corrode or otherwise plug the needle. Further, purging eliminates moisture and oxygen from the septum closed container 11 that may serve to contaminate fluid contained therein. Purge gas may be supplied continuously to the sampler, the flow rate being controlled by any convenient means. Any excess purged gas is simply vented through vent line 27.

Although the invention has been described with reference to its preferred embodiments, those of skill in the art may from this description appreciate changes and modifications which can be made therein which do not depart from the scope and spirit of the invention as described and claimed hereafter.

Claims

1. A sampling system for collecting a fluid sample from a process into a septum closed container, comprising: a reservoir having a first end and a second end, the first end having a first three-way valve connectable to a first line of the process to be sampled and the second end having a second three-way valve connectable to a second line of the process for return of fluid to the process, the first and second valves having a first position wherein the process fluid is allowed to flow from the process through the reservoir and a second position wherein flow of process fluid through the reservoir is stopped and process fluid captured in the reservoir is diverted from the reservoir to a septum closed container; an actuator having a lever for simultaneously actuating the first and second valves from their first position to their second position by movement of the lever from a first position to a second position and resilient means biased to return the lever from its second position to its first position thereby actuating said first and second valves from their second position to their first position.

2. The sampling system of claim 1, further including pressure means for diverting process fluid from the reservoir into the septum closed container by aligning the third port of the second three-way valve with a supply line of a gas to push the process fluid captured in the reservoir into the septum closed container.

3. The sampling system of claim 2, wherein process fluid is diverted from the reservoir to the septum closed container by alignment of the third port of the first three-way valve with the valve port that feeds to the septum closed container to allow the process fluid captured in the reservoir to flow into the septum closed container.

4. The sampling system of claim 3, wherein said first three-way valve is a ball valve the ball of which has a first and second port that are positioned at an angle of 90° relative to each other and communicate with each other and a third port positioned at an angle of 90° relative to said first port and an angle of from about 40 to about 78° relative to said second port and communicating with said first port, said second and third port being of an effective diameter that is less than the diameter of said first port, said first port being in permanent aligmnent and communicating with the first end of the reservoir.

5. The sampling system of claim 4, wherein said second three-way valve is a ball valve the ball of which has a first and second port that are positioned at 90° relative to each other and communicate with each other and a third port positioned at an angle of 90° relative to said first port and communicates with said first port and at an angle of about 40 to about 78° relative to said second port, said second and third ports being of an effective diameter that is less than the diameter of said first port, said first port being in permanent alignment and communicating with the second end of the reservoir.

6. The sampling system of claim 5 wherein said first and second valves are actuated from their first position to their second position by movement of the lever through 90°.

7. The sampling system of claim 6 wherein said second and third port of said first three-way valve is a ball valve have an effective diameter of about 50% of that of the diameter of said first port.

8. The sampling system of claim 7 wherein said second and third port of said second three-way valve is a ball valve have an effective diameter of about 50% of that of the diameter of said first port.

9. The sampling system of claim 8 wherein said second and third port of said first three-way valve have an effective diameter of about 80% of that of the diameter of said first port and said second and third port are at an angle of about 56 to about 62 ° to each other.

10. The sampling system of claim 9 wherein said second and third port.of said second three-way valve have an effective diameter of about 80% of that of the diameter of said first port and said second and third port are at an angle of about 56 to about 62 ° to each other.

11. The sampling system of claim 1, wherein said reservoir is of a predetermined volume that corresponds to the sample size desired.

12. The sampling system of claim 6, wherein said resilient means is a spring biased to return the lever.

13. A method for collecting a sample of a process fluid into a septum closed container, comprising the steps of:

allowing process fluid to flow in the sample system, the sample system having: a reservoir having a first end and a second end, the first end having a first three-way valve connectable to a first line of the process to be sampled and the second end having a second three-way valve connectable to a second line of the process for return of fluid to the process, the first and second valves having a first position wherein the process fluid is allowed to flow from the process through the reservoir and a second position wherein flow process fluid through the reservoir is stopped and process fluid captured in the reservoir is diverted from the reservoir to a septum closed container; said first three-way valve is a ball valve the ball of which has a first and second port that are positioned at an angle of 90° relative to each other and communicate with each other and a third port positioned at an angle of 90° relative to said first port and communicates with said first port and an angle of about 40 to about 78° relative to said second port, said second and third port being of a diameter that is less than the diameter of said first port, said first port being in permanent alignment and communicating with the first end of the reservoir; said second three-way valve is a ball valve the ball of which has a first and second port that are positioned at 90° relative to each other and communicate with each other and a third port positioned at an angle of 90° relative to said first port and communicates with said first port and at an angle of about 40 to about 78° relative to said second port, said second and third ports being of a diameter that is less than the diameter of said first port, said first port being in permanent alignment and communicating with the second end of the reservoir; pressure means for diverting process fluid from the reservoir into the septum closed container by aligning the third port of the second three-way valve with a supply line of a gas to push the process fluid captured in the reservoir into the septum closed container; an actuator having a lever for simultaneously actuating the first and second valves from their first position to their second position by movement of the lever from a first position to a second position and resilient means biased to return the lever from its second position to its first position thereby actuating said first and second valves from their second position to their first position;

manipulating the lever through 90° from a first position to a second position to capture process fluid in the reservoir and to align the third port of the first three-way valve with the septum closed container to allow the process fluid captured in the reservoir to flow into the septum closed container.