US3297843A - Flow-no flow switch - Google Patents

Description

Jan. 10, 1967 Filed NOV. 30, 1964 2 Sheets-Sheet l INVENTOR. MA UR/CE 3. H055 A TTORNE Y Jan. 10, 1967 M. 5. H085 3,297,843

-FLOW-NO FLOW SWITCH Filed Nov. 50, 1964 2 Sheets-Sheet 2 IL V \48 INVENTOR.

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ATTORNEY United States Patent 3,297,843 FLOW-NO FLOW SWITCH Maurice S. Hoss, Tulsa, Okla, assignor to Combustion Engineering, Inc., New York, N.Y., a corporation of Delaware Filed Nov. 30, 1964, Ser. No. 414,775 1 Claim. (Cl. 20081.9)

This application is a continuation-in-part of Serial No. 391,989, filed August 25, 1964.

The present invention relates to devices for manifesting the flow of fluids through a conduit. More particularly, the invention relates to a detector for the intermittent flow of oil well production as the production is pumped.

Pumping oil wells are very individualistic. Each well has its own type of production, with a particular ratio of liquid and gas. Legal restrictions on the amount of production permitted to be taken from each well additionally characterizes the daily cycle of operation.

It is generally desirable that the pumper personnel keep informed as to whether a well has pumped off. It is further desirable that a well which has pumped its allowable quantity of production, or a well which has been relieved of available production for the moment, be automatically shut down to save wear and tear on the pumping equipment as well as fuel to operate the pumping equipment. At the very least, a manifestation of the flow of produced fluids in an oil well is highly desirable.

Quite often the liquids of pumped well production come in slugs, or spurts. Between production of liquid slugs, it may not be desirable to manifest that flow has temporarily' halted, because of the particular characteristics of the well operation. A time-delay mechanism is needed, in combination with a primary element responsive to liquid flow. With a time-delay mechanism the response of the flow detector of the no-flow condition will be manifested to give a true picture of the well condition.

An object of the present invention is to sense the flow of liquids in a conduit and manifest cessation of the flow a predetermined length of time after the flow has stopped.

Another object of the invention is to detect the flow of liquids in the conduit without a great amount of restriction of the flow and to manifest cessation of the flow in predetermined lengths of time after the flow stops.

Another object of the invention is to give a positive manifestation of the flow of liquid from an oil well and to interrupt the operation of the pumping equipment of the well when the well is pumped off.-

The present invention contemplates a valve in the production conduit of an oil well. A time-delay unit is mounted near the stem of the valve element and controlled by the stem in actuating a switch. When the well has pumped off its liquid, a device will be actuated by the switch to manifest this information.

The invention further contemplates that a hydraulic mechanism embody the time-delay unit mounted near the valve stem. This mechanism comprises a simple chamber filled with hydraulic fluid and a shaped body including a magnet within the fluid. The shaped body is arranged within the chamber so as to travel over a fixed path through the fluid. A magnet mounted on the valve stem repulses the magnet in the chamber fluid when the valve stem is moved towards the magnet in the chamber fluid. When the valve stem retreats, gravity returns the magnet in the chamber fluid to its original position. The magnet in the chamber fluid is shaped so the fluid will force it to move at different rates.

The invention further contemplates that the hydraulic mechanism comprise a chamber filled with hydraulic fluid and a magnetic body within the fluid, sized so as to fall under the force of gravity at a fixed rate.

The invention further contemplates that a manifesting device actuated by the magnet in the fluid comprise an electric switch which can, in turn, control the operation of the well pump.

Other objects and advantages of the present invention will become readily apparent from the following detailed description of the invention with a specific reference to the accompanying drawings in which:

FIG. 1 illustrates a complete system in which the present invention is embodied, including the pumping unit delivering production to a conduit in which a detector employing a shaped magnet is mounted, and

FIG. 2 is a sectioned elevation of a detector similar to the detector of FIG. 1, but employing a magnet sized to fall by gravity at a predetermined rate.

Referring to FIG. 1, an oil well pumping unit 1 is shown in perspective. Pumping unit 1 delivers the production to a conduit 2. Conduit 2 takes the produced fluid through a valve body 3 and into a conduit 4. Conduit 4 illustrates the produced liquid being delivered to storage facilities 5. As a practical matter, the production may be delivered to some form of field processing equipment, or a gathering system, before ultimate delivery to storage facilities.

Pumping unit 1 is essentially a conventional linkage between a prime mover 10 and a reciprocated polish rod 11. The fuel system for engine 10 is of no present concern and is not illustrated. Engine 10 is indicated as linked to reciprocate polish rod 11. Polish rod 11 is shown extending into a common stufiing box 12 for connection with the pump downhole of the well.

Obviously, there is much equipment at the well head which could be illustrated. However, the present invention does not require this disclosure to illustratethe concepts embodied.

Valve body 3 is included in the production conduit by attachment between conduit 2 and conduit 4. Within body 3 a seat member 15 is placed in the opening of Web 16 so that all of the production from the well flows through seat member 15.

A valve element 17 is arranged to engage seat member 15. More specifically, valve element 17 is mounted on stem 18, and stem 18 is re-ciprocated to engage, and disengage, valve element 17 with seat 15.

The arrangement disclosed in FIG. 1 shows how the flow of fluid from conduit 2 will travel upward through seat member 15 and exert a lifting force on valve element 17. It is desired that valve element 17 descend and engage seat member 15 when the flow of production from conduit 2 stops. When the force from the production fluid is removed from valve element 17, gravity carries stem 18 and valve element 17 downward, engaging element 17 and seat 15.

The foregoing reciprocation of valve element 17 and stem 18 actuates a time delay mechanism which controls an electrical switch. On the upper end of stem 18 is mounted a magnet. The reciprocation of stem 18 causes magnet 20 to reciprocate, travel, over a fixed path.

Above magnet 20, a body of liquid 21 is contained. A second magnet 22 is placed Within liquid body 21. As magnet 20 travels upward, toward magnet 22, magnet 22 is repulsed, the poles of the two magnets being arranged to cause this repulsion. Magnet 22 travels upward, through liquid 21. When magnet 20 travels downward, away from magnet 22, gravity causes magnet 22 to fall through liquid 21.

Switch 23 is mounted on the external surface of the container of liquid 21. Switch 23 is adjustable so that it will be actuated by magnet 22 at a predetermined point in the travel of magnet 22.

Magnet 22 is moved upward and downward within liquid 21 by the forces of gravity and the magnetic field of magnet 20. The rate of travel of magnet 22 through liquid 21 is fixed by the rate of travel of magnet 20, to some degree. However, the basic rate of travel is determined by the resistance provided by the surface of magnet 22 moved through liquid 21.

The magnet 22 is provided with a shape which causes the magnet to move in one direction at a rate greater than its movement in its second direction. More specifically, magnet 22 is shaped to move upwardly at a greater rate than it moves downwardly. To provide this differential in rate, the magnet 22 is given an effective shape which is conical, the base of the cone pointing downward.

It is possible to provide the complete magnet 22 with the desired conical shape. However, it is more feasible to encase the magnet in a plastic material with the desired shape. The casing 24 is more easily shaped initially and its shape more easily altered as may be later desired.

As stem 18 is reciprocated, causing magnet 22 to reciprocate, switch 23 is actuated at predetermined points in the travel of magnet 22. More specifically, the switch 23 is mounted at a position where it will be actuated by magnet 22. The present disclosure shows switch 23 as attached to control pump engine 10. One mode of operation would result in grounding the magneto or pump engine a predetermined length of time after fluid ceases to flow through valve body 3.

To gain access to seat member 15, body 3 has an opening 30 in its side and a bonnet member 31 is mounted over opening 30. A casing 32 is extended through an opening in bonnet 31.

The stem 18 is given a cross-sectioned multi-sided shape to act as a guide within the bore of casing 32 with minimum friction and magnet 20 is mounted on the top of the stem. The lower end of casing 32 acts as an upper limit stop for valve element 17. The casing 32 extends upward to form the container for liquid 21 above the reciprocating end of stem 18.

To form container 35, casing 32 is counterbored from its top. The upper and lower counterbores are of the lengths to leave a wall 36 between them to form the bottom of container 35. The top of container 35 is a cap 37 which may be screwed into, and sealed to, casing 32. Liquid 21, magnet 22 and casing 24 are then sealed within container 35, the magnet 22 moving up and down to actuate switch 23 -at predetermined points in its travel.

The operation of the structure embodying my invention has been fairly well described as the particular parts have been designated. The general plan is to place the indicator in a pumping well production conduit to provide a pumper with definite information on the flow of production from the well. Many pumped wells are operated for unnecessary periods of time after they have pumped off. Often the pumper has no alternative to opening some valve in the production conduit to observe if fluid is still flowing from the pumped well. This is not only a great inconvenience, but a waste of production while promoting an unsightly condition around the well head.

Of course, the production of fluids from these pumped wells is often quite erratic. Each well has its own personality in this regard. My invention provides the pumper the very convenient means with which to continually sense any fluids that are produced from the well and to manifest when the production of fluid slugs have slowed to a predeterminend frequency.

FIG. 2 illustrates another form for the time-delay mechanism which controls an electrical switch. It has been found that if the magnet in the fluid is properly sized it is not necessary to encase the magnet in a plastic material with the desired shape to obtain the rate of fall required.

In FIG. 2, a valve body 40 is shown, included in a conduit 41. Within body 40 a seat member 42 is placed in the opening of web 43 so that all of the production from conduit 41 flows\through the seat member 42.

A valve element 44 is arranged to engage seat member 42. More specifically, valve element 44 is mounted on stem 45, and stem 45 is reciprocated in housing 45A to engage, and disengage, valve element 44 with seat 42.

The arrangement disclosed in FIG. 2 shows how the flow of fluid from conduit 41 will travel upward through seat member 42 and exert a lifting force on valve element 44. It is desired that valve element 44 descend and engage seat member 42 when the flow of production from conduit 41 stops. When the force from the production fluid is removed from valve element 44, gravity carries stem- 45 and valve element 44 downward, engaging element 44 and seat 42.

The reciprocation of valve element 44 and stem 45 in housing 45A actuates the particular time delay mechanism of FIG. 2 which controls an electrical switch. On the upper end of stem 45 is mounted a magnet. The reciprocation of stem 45 causes magnet 46 to reciprocate, travel over a fixed, linear, path.

Above magnet 46, a body of liquid 47 is contained in chamber 50 which is integral with the upper end of housing 45A. A second magnet 48 is placed within liquid body 47. As magnet 46 travels upward, toward magnet 48, magnet 48 is repulsed, the poles of the two magnets being arranged to cause this repulsion. Magnet 48 travels upward, through liquid 47. When magnet 46 travels downward, away from magnet 48, gravity causes magnet 48 to fall through liquid 47.

Switch 49 is mounted on the external surface of the container 47. Switch 49 is adjustable so that it will be actuated by magnet 48 at a predetermined point in the travel of magnet 48.

Magnet 48 is moved upward and downward within liquid 47 by the forces .of gravity and the magnetic field of magnet 46. The rate of travel of magnet 48 through liquid 47 is fixed by the rate of travel of magnet 46, to some degree. However, the basic rate of travel is determined by the resistance provided by the clearance between the walls of chamber 50 and magnet 48 in which fluid 47 flows as the force of gravity pulls downward on magnet 48 and the repelling force of magnet 46 pushes upward on magnet 48.

The force of magnet 46 is made great enough to push magnet 48 to the top of chamber 50 quickly. When magnet 46 is lowered, the force of gravity pulls magnet48 downward at a slower rate. The rate of travel in each direction is dependent upon the viscosity of the fluid 47, A

the clearance between magnet 48 and the walls of chamber 50 and the force of magnet 46. The operation otherwise is similar to the operation of the structure of FIG. 1.

From the foregoing it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the apparatus.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. contemplated by and is within the scope of the claim.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

The present invention having been described, what is claimed is:

A fluid flow indicator including,

a conduit through which the flow of fluid is indicated,

a valve seat in the conduit through which the fluid flows,

a valve element adapted to cooperate with the valve seat as the fluid flows through the seat,

a housing connected to the conduit,

a first magnet within the housing and connected to the valve element so as to travel a fixed path as the valv element cooperates with the valve seat,

This is' 6 a liquid filled chamber integral with one end of the and a circuit actuated by the switch to indicate when housing, fluid flows through the conduit. a second magnet arranged within the chamber so as to move linearly and sized to have a predetermined References Cited y the Examine! clearance with the internal walls of the housing where- 5 UNITED STATES PATENTS by the linear movement is at a first rate through the liquid when the second magnet is repulsed by the fi 200 87 [first magnet and at a second rate through the liquid 1 5 aswde 2 4 when the second magnet is moved by gravity, 7 3/ 96 Bree 00 3 X a switch positioned adjacent the path traveled by the 10 BERNARD A GILHEANY Prima Examiner second magnet so as to be operated by the second ry magnet as the second magnet reaches a predetermined G. MAIER, Assistant Examiner. position in its path,

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