US2163436A

US2163436A - Chemical feeding apparatus and automatic control therefor

Info

Publication number: US2163436A
Application number: US143770A
Authority: US
Inventors: Raymond Gwynne; Walden W Mason
Original assignee: Individual
Current assignee: Individual
Priority date: 1937-05-20
Filing date: 1937-05-20
Publication date: 1939-06-20
Anticipated expiration: 1956-06-20

Description

June v20, 1939. G. RAYMOND ET AL CHEMICAL FEEDING APPARATUS AND AUTOMATIC CONTROL THEREFOR Filed May 20, 1957 4 Sheets-Sheet l June Z0, 1939. G. RAYMOND ETAI. 2,163,436

CHEMICAL TEEDING APPARATUS AND AUTOMATIC CONTROL, THERETOR Filed May 20, 1957 4 Sheets-Sheet 2 l| IHII INVENTORS ynne Raymond, aad 9 72 Ewa/den W yMaso/1A ATToNEY June 20, 1939. G. RAYMOND Al. 2,163,436

CHEMICAL FEEDING APPARATUS AND AUTOMATIC CONTROL THEREFOR Filed May 20, 1937 4 Sheets-Sheet 4 /76 ...MM ai@ /74 les /64 W IN V EN TO R 5 G WW1/le Raymond, ab,

ATTORN EY Patented June 20,A i939 CHEMICAL FEEDING APPARATUS AND AUTOMATIC CONTROL THEREFOR Gwynne Raymond, Oklahoma City, Okla., and

Walden W. Mason, Kansas City, M0.

Application May 20, 1937, Serial No. 143,770

13 Claims.

This invention relates to a chemical feeding apparatus and an automatic control valve gear therefor, whereby a chemical or the like is injccted into a flowing stream of fluid, such as the 5 flow from an oil well, and has for its principal object to provide a simple and relatively inexpensive apparatus which is of positive operation and adapted to function at predetermined intervals.

Other important objects of the invention are to provide an automatic control actuated by a uid pressure medium; to provide a relatively simple adjustment for varying the time interval between the injecting periods; and to provide a i6 toggle mechanism whereby the control valve is instantly moved to and from its respective positions so as to reduce the amount of pressure medium required to operate the apparatus.

In accomplishing these and other objects of 20 the invention, as hereinafter pointed out, we have provided improved detailsof structure, the preferred forms of which are illustrated in the accompanying drawings, wherein:

Fig. l is a. perspective View of .a chemical feeding apparatus, shown in use for injecting a chemical into the ilow line of an oil well and constructed and equipped with an automatic control valve gear embodying the features of the present invention.

the chemical feeder, particularly illustrating the control valve gear and .the actuating mechanism for operating the pump whereby chemical is periodically injected into the ow line.

35 Fig. 3 is a horizontal section on the line 3-3 of Fig. 2.

Fig. 4 is an enlarged detail section through the control valve and the actuating mechanism therefor.

Fig. 5 is a vertical section through the apparatus on the line 5 5, Fig. 4.

Fig. 6 is a horizontal section on the line 5 6, Fig. 4.

Fig. 7 is a sectional view of a modified form of control valve and gear.

Fig. 8 is a plan view, partly in section, of the form of the invention shown in Fig. '7.

Fig. 9 is a section through a. further modified form of control valve.

Fig. 10 is a detail section through a still further modiied form of control valve.

Fig. 1l is a section on the line H-H of Fig. 10.

Fig. 12 is a section through another form of control Valve.

Fig. 13 is a detail View of a portion of the Fig. 2 is an enlarged sectional view through Valve spring employed in the form of invention illustrated in Fig. 12.

Referring more in detail to the drawings:

l designates an oil well having a flow line 2, through which flow from the well is discharged to an oil and gas separator or similar tank (not shown), and wherein the liquid reacts with a chemical to effect breaking of any water and cil emulsion contained in the flow.

In order that the chemical will have as long a contact with the fluid as possible, it is best practice to introduce the chemical directly at the point of the well. Means is, therefore, provided whereby the chemical is introduced in measured amounts, and which permits suitable adjustment whereby the amount of chemical admitted may be regulated substantially in accordance with the volume of well flow. An apparatus constructed in accordance with the present invention is particularly adapted for this purpose and we have, therefore, illustrated and described our improved apparatus for this use, and since it is adapted for other purposes, we do not wish to be limited to the specific application of the invention as described.

Connected into the flow line 2 is a ow 'regulating valve 3, whereby the flow of the well is limited to a given amount over a certain time period, and connected into the line, in the inlet side of the Valve, is a conduit 4, leading from a chemical feeder generally indicated 5, and which is shown as including a substantially cylindrical tank 5 having an annular wall 'l closed at the ends by upper and lower disk-

shaped heads

8 and 9. Depending circumferentially of the wall l is a cylindrical skirt i0, forming a diaphragm and pump compartment Il to which access is had through suitable door openings I2, which are normally closed by hinged doors i3. Formed in the top 8 is a fill opening I4 having a depending strainer l5, through which the chemical is poured into the tank. The fill opening i6 is normally closed by a threaded plug I6, having a lateral ange il engaging a gasket I8 that is carried on an annular seat i9 to provide a gas-tight joint.

The plug 9S has a pressure release port 2U, normally closed by a spring loaded valve 2i to relieve excessive pressures that may occur in the tank. The valve 2| has a port 22 that is closed by an inwardly opening valve 23 which is kept closed by a spring 24, but which is adapted to open in case a vacuum should be drawn in the tank.

Chemical. is discharged from the bottom of the tank through an outlet pipe 25, leading to the inlet of a pump 26 -that is located in the compartment Il. Pressure is maintained in the tank through a. conduit 21 that is connected with the top thereof, and which leads from a pressure reduc-ing valve 28 also located within the compartment the iiow through the line being con- .trolled by a stop or shut-off valve 29.

The mechanism within the compartment is supported upon a frame 39, comprising vertical leg portions 3| and 32, carried on a disk-like plate 33 forming the bottom of the compartment. The leg portions 3| and 32 are provided with foot or flange portions 34 which are secured to the plate 33 by fastening devices, such as bolts, 35. Connected at the top of the leg portions 3| and 32 is an annular ring 3'6, forming a seat for the periphery of a flexible diaphragm 31. The diaphragm 31 is covered by a cap 38, having an annular flange 39 cooperating with the seat to clamp the periphery of the diaphragm therebetween, the cap being secured by fastening devices, such as cap screws, 40 extending through suitable openings in the anges and through aligning openings in the diaphragm, as'shown in Fig. 2. The central portion of the cap is offset from the attaching portion of the diaphragm to form a diaphragm chamber 4|, into which a pressure medium is discharged from a pipe 42 which is connected with the outlet connection 43 of a control valve 44. The inlet 45 of the control valve is connected by a pipe 46 leading from the pressure reducing valve 28. 'Ihe pressure medium is supplied to the reducing valve 28 by a connection 41 with a trap 48, wherethrough gas is delivered from a` supply pipe 49 leading from the casing head 50 of the well 'I'he trap 48 includes a cylindrical tank carried by the supporting brackets 5| and 52 whereby the chemical tank is anchored to a post 53, the axis of the tank being arranged vertically. The gas inlet line 49 opens tangentially into the tank at a point below a perforated partition 54 that supports a body of filtering material 55 to lter the -gas on its way to the connecting line 41 that is connected with the top of the tank. Any entrained liquid or solid matter carried in the gas gravitates to the bottom of the tank and is drawn off from time to time through a drain valve 56.

The diaphragm 31 is caused to pulsate for operating the chemical feeding pump 26, now to be described. The pump 26 is mounted on the plate 33, and includes a block 51 having a piston chamber 58 in which a reciprocating piston 59 is mounted, the piston being operable through a suitable packing gland 60, and has its stem 6| connected by means of a. yoke 62 with a diaphragm stem 63. The stem 63 is reciprocably mounted within a threaded bushing 64 that is threaded through a boss 65 on a cross bar 6'6 of the frame 30. The stem 6| extends freely through a washer 62 fixed to the yoke 62 and carries a nut 6| that engages the upper face of the washer. The stem 6I also carries jam-nuts 6| that are adjustable to and from `the lower face of the washer 62'. Movement of the'pump piston can, therefore, be adjusted from maximum, when the nuts 6I' and 6| are tightly engaging the respective sides of the Washer 62', to a minimum when the spacing between the nuts is regulated to approach the stroke of the diaphragm. Threaded on the upper end of the stem is a backing plate 61 engaging the under side of the diaphragm. The diaphragm is normally retained inits uppermost position and the piston at the upper end of its stroke, by a coil spring 68 that is sleeved over the bus-hing and has its lower end bearing against the boss '65 and its upper end against the backing plate 61. It is thus obvious that when gas is admitted into the diaphragm, through the pipe 42, the diaphragm is moved downwardly against action of the spring 68, and causes the piston 59 to move downwardly in the cylinder, displacing some of the chemical that has been previously drawn therein by the preceding upstroke of the piston.

The chemical line 25 is connected to the pump by a valve bushing 69, having an inlet portion 10 controlled by a spring pressed intake valve 1|. 'I'he valve 1| is normally retained in seated position but is adapted to open on the upstroke of the piston to allow flow of chemical into the piston chamber. As soon as the piston reaches the upper end of its stroke, incidental to action of the spring 68 and release of gas from the diaphragm chamber, the valve 1| is closed by its spring to trap the indrawn chemical in the piston chamber. Upon the downstroke of the piston, responsive to pressure of the gas, when admitted to the diaphragm chamber, the chemical is displaced from the pump cylinder through a lateral port 12, leading to an outlet port 13 that is in communication with -a valve port 14 in a dis-` charge valve bushing 15. The bushing 15 is threaded into the pump block 51, andv has a seat 16 for a ball valve 11 to prevent back ow through the pump. Also formed in the bushing, above the valve 11, is a seat 18 that is normally engaged by a spring pressed valve 19. Threaded in the bushing is an outlet fitting 80, having a lateral branch 8| connected with the conduit 4, previously mentioned. The fitting is also provided with a suitable pressure gauge 82.

The pressure reducing valve 28 is adjusted so that the gas is supplied to the diaphragm chamber at substantially constant pressure, andA at sufiicient 4value to effectively operate the diaphragm and piston against action of the spring 68 and the pressure of the fluid moving through the ilow line 2. Since gas pressure is supplied to the chemical tank through the pipe 21 to act upon Athe body of chemical therein, a steady ow of chemical is effected to the pump under an initial pressure, thereby tending to reduce the power required bythe pump in injecting the chemical under ow line pressure.

'Ihe control valve 44 forms an important part of the present invention, and isillustrated in detail in Figs. 4, 5 and 6. The valve includes a valve body 83, having a valve chamber 84 communicating with the pipe 42 through a lateral port 85. Formed in the valve chamber, on opposite sides of the port 85, are annular, oppositely vfacing shoulders 86 and 81 for supporting

valve seat members

88 and 89, having

ports

90 and 9| for ow of gas to and from the pipe 42 and through an exhaust line 92. The connection 46 of the control valve communicates with the valve chamber at a point above the valve seat 88, through a port 93, which is under control of a needle valve 94. The needle valve has its stem threaded in a lateral extension oi the valve body and -is manipulated to adjust the effective area of the port 93 by means of a knurled head 96, the needle valve being retained in adjustment by a jamnut 91 threaded upon the stem and engaging against the lateral extension 95. The exhaust line 92 is threaded into a fitting 98, having a portion 99 projecting into a chamber |80 formed as a part of the valve body, the projecting portion the cross bar ||9. A portion of one side wall being provided with ports |0| communicating with the interior of the chamber |00. The seat member 88 is of plug-like character and is threaded in the upper end of the valve chamber to seat against the shoulder 86, and the seated end thereof has an annular valve seat |02 encircling a bore |03 which forms a gas passageway communicating through lateral openings |04 with the port 93. The other member 09 is of sleeve-like character and is threaded into the opposite end of the valve chamber, from within -the chamber |00, to engage the shoulder 81. The member 89 has an annular valve seat |05 encircling a reduced bore |06 of `thesleeve. Located between the seats is a ball valve |01 that is adapted to engage either of said seats under control of a I trip mechanism, now to be described.

loosely movable through the valve seat to lift the ball from the seat |05 to valving engagement with the seat |02. When the ball is seated on the seat |05, the lower end of the member |00 rests upon the stop 99. ball valve is normally urged against the rod-like end |09, or the seat |05, by a coil spring ||0 that is mounted in the bore of the valve seat member 8B, and has one end bearing against the ball and its other bearing against the closed end of the bore. The member |08 has a collar-like guide provided with gas passage` ways ||2. To provide snap action, the member |08 is reciprocated through a trip mechanism l|3 that includes a yoke-shaped lever ||4, having a hub portion ||5 that is pivotally mounted von a cross pin ||6 carried by the opposite side walls of the chamber |00 at one end thereof. The yoke also includes spaced arms ||1 and ||8 projecting from the ends of the hub portion ||5, on opposite sides of the member |08, and the free ends thereof are connected by a. cross bar ||9 at ya point spacedinwardly from the ends thereof. The cross bar has a web-like flange provided with a slot |20 to engage the stem of an actuating rod |2 whereby the yoke is rocked upon the pin ||6.

The bar member |08 is provided on its lower end with V-shaped grooves |22 and |23 respectively, aligning with grooves |24 and |25 that are provided in the hub portion ||5 and the cross bar ||9. Seated within the pair of grooves |22-|24 and |23;|25 are pairs of knife edge bearing members IZB-|21 and. |28|29 of toggles |30 and |3|. The toggles |30 and |3| also include springs |32 and |33 shaped to form spaced arms |34 anchored to the ends of the pairs of bearing members and` provided with yieldable coil portions |35. The total length of the toggles is greater than the 'spacing between the bottoms of the grooves |24 and |25 sothat the pivotal points of the knife edge bearings are normally offset to one side or the other of a plane extending through the bearing points of the grooves |24 and |25. The actuating rod |36 is carried by the diaphragm backing plate, and projects downwardly through a packing box |31 into the chamber |00 to engage in the slot |20. The rod has stop collars |38 and |39 thereon, adapted to engage the respective sides of the flange of the bar ||9, to effect movement of the lever ||4 responsive to movement of the diaphragm.

Movement of the lever ||4 is limited under throw of the toggles by pads |40 and |4| respectively carried by the top and bottom walls of the chamber |00 and adapted to be engaged by tom of the tank so that gas may be discharged into the chemical to effect agitation thereof, the line |49 being provided with a shut-off valve |50.

An apparatus constructed and assembled as described operates as follows:

Assuming that a quantity of chemical has been inserted in the chemical tank, and that the lines 49 and |49 are connected with the casing head of the Well and the line 4 with the ow line 2, gas is supplied from the casing head through the line 49, into the trap.48, Where the entrained liquid and solid matter gravitate to the bottom thereof. The separated gas passes upwardly through the ltering material and is discharged -through the line 41 to the pressure reducing valve which is set to pass the gas through the

lines

21 and 46 at the desired pressure. Pressure of the gas admitted to the tank, through the line 21, is indicated on the gauge |48, and

acts on the body of chemical in the tank to effect positive feed thereof through' the pipe 25 to the inlet of the pump 26. Should excessive pressures occur in the chemical tank they .are relieved' through lifting of the valve 2| until the pressure is dropped to the point where the valve spring will effect closure thereof. Likewise should minus pressures occur in the tank, the valve 23 will open to allow entrance of air to relieve the vacuum. The stroke of the pump is adjusted by spacing the jam-nuts 6| ,from thewasher of the yoke 62 the desired amount to produce the desired movement of the piston relatively to the full stroke of the diaphragm.

- Assumingv that the diaphragm and piston are in their uppermost position, as shown in Fig. 2,

ment of the diaphragm against action of the.

spring 66. When the washer 62' engages the upper jam-nut the diaphragm becomes effective to move the piston to displace chemical from the piston lchamber out through the

ports

12 and 13, 4

and past the

valves

11 and 19, and through the line 4 into the fluid flowing from the oil well. Downward movement of the diaphragm carries the stop collar |38 on the rod- |36 into engagement with the web of the.connecting bar on the yoke-like lever, to move the lever downwardly until the contact points of .the outer knife bearings have passed the off-center position relatively to the inner knife point bearing members, whereupon stored up tension in the spring will snap the bar member in an upward direction, lifting the ball into engagement with the upper seat, thereby suspending flow of gas through the upper valve seat and opening communication-between Il the diaphragm chamber and the exhaust pipe through the lower valve seat and chamber |00. The spring 68 then comes into play to' cause retractive movement of the diaphragm, which carries the piston therewith on the succeeding intake stroke, allowing an additional quantity of vchemical to be'drawn into the pump cylinder.

When the collar |39 engages the yoke-like lever, the lever is carried in an upward direction until the outer knifeI edge bearings pass dead center position relative to the inner knife edge bearings, whereupon the springs again come into play to cause downward snap movement of the valve control bar, thereby allowing the ball to engage the seat on the exhaust side, and to open communication through the seat on the pressure side to again estabish flow of gas to the diaphragm chamber. The apparatus will thus `continue to operate at definite, predetermined periods, according to the flow rate of .the gas as regulated by the needle valve 94.

later described. The valve also includes a pilot |64 guidingly supported within the inlet port |65. Extending laterally from the side of they valve body is a bore |66, having a threaded outer portion |61 to accommodate the threaded shank |68 of a needle valve |69. The inner end of the bore communicates through a port |10 with the inlet port |1| and through an axial port |12 with the port |65.' The needle valve includes a pointed end |13 that is adapted to control the effective area of the port |10 sopas to regulate the rate of flow of gas admitted to the diaphragm chamber upon opening of the valve from the seat |59 and closing of the -valve on the seat |58. The threaded shank of the needle valve projects from the valve body, and sleeved thereover is a coil spring |14 having one end engaging against the valve spring providing sufficient resistance'to retain .body and the other against a disk-like collar |15. The head |16 of the shank is provided with a transverse slot wherein a-screwdriver may be inserted to effect rotaiion of the valve, the

the valve in adjusted position.

When the diaphragm is in its uppermost position the toggle yoke is engaging the stop 282. In this position the valve plug is engaging the seat |58 to close communication of the diaphragm will then ow past the needle valve, into the diaphragm chamber. When a sufficient amount of pressure medium has been admitted to the diaphragm chamber so that the pressure acting on the diaphragm overbalances its spring, the diaphragm is. moved downwardly, effecting a displacement stroke of the pump pist'on. The toggle lever swings downwardly toward the lower stop 203. As soon as the spring 20| has passed dead center position relatively to the shafts |99 and |19, the spring becomes effective to throw the lever |8| in the opposite direction, causing closure of the port |65 and opening of the vent port so that the supply of pressure medium is shut off and the pressure medium in the diaphragm chamber is allowed to exhaust to atmosphere. The

-valve thus will continue to operate in substan- The valve body in the form of the invention illustrated in Fig. 9 is substantially the same as that illustrated in Fig. 7', however, the valve 285 thereof does not directly control the supply port 206. In this form of the invention, the valve body is provided with a single threaded plug 201, having an external valve seat 208 through which pressure medium from. the diaphragm chamber,-

is vented to atmosphere, and onwhich the valve 205 seats under control of the toggle mechanism. In the form illustrated in Figs. 10 and 11, the

dvalve actuating lever 289 has a collar portion 2|0 fixed to a threaded diaphragm actuated rod 2|I. The lever 289 is secured on the rodby nuts 2I2 and 2|3 engaging the respective sides thereof. Extending upwardly from the valve body is a guide post 2M, carrying a stop 215 to resist movement of a bow-shaped spring 2|6 during upward movement of the lever 209. When the diaphragm is in its uppermost position, the exhaust port 2H is closed by a valve 2|8 that is carried by the spring. 'I'he pressure medium being admitted through the valve is then effective in building up pressure in the diaphragm chamber. As the diaphragm moves downwardly the lever 209 is moved therewith, storing up tension in the spring 2I6. As soon as the lever n209 is moved downwardlyv a sutilmente-distance, the stored up tension in the bow-shaped spring causes the spring to reverse its curvature and engage the stop 2I5, thereby providing quick opening of the exhaust port 2H and allowing the pressure medium to exhaustfrom thel diaphragm chamber. As soon as a sufficient amount'of pressure has escaped through the port 211, movement of the diaphragm is reversed to again cause seating of the valve so that the pressure medium is again effective in operating the diaphragm.

The form of the invention illustrated in Figs. 12- and 13 employs a valve 2I9 that is carried by a leaf type spring 220, having a deformation 22| to cause snap movement of the valve when the operating lever 222 has moved a predetermined distance.

While the structures illustrated in Figs. 9 to 13 inclusive are slightly more wasteful of gas, this wastage is not excessive and they are entirely practicable for the purposes for which they are intended.

From the foregoing it is obvious that I have provided an automatic feeder and control valve gear therefor, which may be used for feeding chemical into a flow line, and that the controlling apparatus is of simple and relatively inexpensive construction, and adapted to function at predetermined intervals so as to maintain the feed of the chemicals in proportiony to the amountof liquid being discharged from the oil well.

What we claim and desire to secure by Letters Patent is:

1. In an apparatus for introducing treating chemical into the owfrom an oil and gas well, a chemical supply means, a reciprocatory pump, means connecting the chemical supply means with the pump, means connecting discharge of thepump withthe well flow, means for delivering gas from said well to the chemical supply means whereby chemical is delivered to the pump at approximately the pressure of the flow, a diaphragm actuator' coiected with the pump, means supplying gas to the diaphragm actuator for operating the pump to inject a charge of Achemical into the well flow, and means for controlling said ga's supply to the diaphragm actuator for automatically effecting reciprocation of the pump.

2. In an apparatus for introducing treating` chemical into the flow from an oil and gas well, a .chemical supply means, a reciprocatory pump, means connecting the chemical supply means with the p ump, means connecting discharge of the pump with the well flow, means for delivering gas from said well to the chemical supply means whereby chemical is delivered to the pump at approximately the pressure of the ow, a diaphragm actuator connected with the pump, means supplying gas to the diaphragm actuator for operating the pump `to inject a charge of whereby chemical is delivered to the pump at approximately the pressure of the flow, a diaphragm actuator connected with the pump, means supplying gas to the diaphragm actuator for operating the pump to inject a charge of chemical into the well ow, a valve in said gas supply means for bleeding gas from the diaphragm actuator to eifect charging of the pump, and means for actuating the valve responsive to movement of said actuator, said connection between the diaphragm actuator and pump having an adjustable lost motion connection for selectively varying the stroke of the pump relative to the movement of the diaphragm actuator.

4. In an apparatus for introducing treating chemical into the fiow from an oil and gas well, a chemical supply means, a reciprocatory pump, means connecting the chemical supply means with the pump, means connecting discharge of the pump with the well ow, means for delivering gas from said well to the chemical supply means whereby chemical is delivered to the pump at approximately the pressure of the flow, a diaphragm actuator connected with the pump, means supplying gas to the diaphragm actuator for operating the pump to inject a charge of chemical into the well ow, a valve in said gas supply means for bleeding gas from the diaphragm actuator to e'ect charging of the pump, means for actuating the valve responsive to movement of said actuator, and a trip mechanism connected with the diaphragm actuator for operating the valve.

5. In combination with an oil flow line and a gas supply, a chemicalfceding means connected with the flow line, pressure actuated means for.

operating said feeding means, means connecting the pressure actuated means with the gas supply for supplying gas thereto, means regulating ow of the gas to the pressure actuated means, and an operating connection between the gas regulating means and the pressure actuated means for effecting automatic periodic actuation of the feeding means.

6. In combination with an oil and gas well having a flow line and a gas take-01T connection, a chemical feeder including a pump, means supplying a chemical to the pump, means connecting the pump with the flow line, pressure actuated means, means connecting the lpressure actuated means with the pump, means supplying gas from said take-off connection to the pressure actuated means for effecting` operation of the pump, and gas control means in said supply means for effecting periodic actuation of said.

pump.

7.. In combination with an voil ow line and a gas supply, a chemical tank, a pump housing, a pump in the pump housing, means connecting the tank with the pump, a diaphragm chamber ply with the diaphragm chamber, a valve in said gas supply connecting means for controlling flow of gas to and from the diaphragm chamber, and valve operating means actuated by the diaphragm for operating said valve to effect automatic operation of the pump and periodic injection of chemical into said oil flow line. 1

8. In combination with an oil flow line and a gas supply, a chemical tank, a pump housing, a

pump in the pump housing, means connecting.

the tank with the pump, a diaphragm chamber in the pump housing, a diaphragm in said chamber, means operably connecting the diaphragm with the pump, means connecting the gas supply With the diaphragm chamber, a valve in said -gas supply connectingV means for controlling ow of gas to-and from the diaphragm chamber, valve operating means actuated by the diaphragm for operating said valve to effect automatic operation of the pump and periodic injection of chemical into said oil flow line, and means connecting the gas supply with the chemical tank to supply the chemical to the pump under pressure of said gas supply.

9. An apparatus of the character described, including a flow line of an oil and gas well, a chemical feeding apparatus, including a tank, pressure actuated means for feeding chemical from the tank into the flow line, means supplying gas from the Well to said pressure actuated means, and means supplying, said gas to the tank whereby a chemical in the tank is delivered to the pressure actuated' means to facilitate injection of the chemical into the flow line.

10. An apparatus of the character described including a flow line of an oi1`and gas Well, a chemical feedingapparatus, including a tank, a chemical pump having connection with the tank, pressure actuatedmeans foroperating the pump, means connecting discharge side of the pump with lthe flow line, means supplying gas from said Well to the pressure actuated means to operate the pump, and means supplying said gas to the tank wherebyv a chemical in the tank is delive'red to the pump under pressure to facilitate injection of the chemical into the ow line.

. 11. In an apparatus of the character described, a pump having a piston, pressure-actuated means for operating the piston, means operably connecting the pressure actuated means with the pump piston, means supplying a pressure mevlatlng theeffective movement of the piston in response to movement of the pressure actuated means. 4

12. In an apparatus of the character described, a pump having a piston, pressure actuated means for operating the piston, means operably connecting the pressure actuated means with the pump piston, means supplying a pressure medium to the pressure actuated means, a valve controlling flow of pressure medium to the pressure actuated means, means operated by the pressure actuated means for operating the valve to adjust periodic operation of the pump piston, a lost motion connection in said connecting means, and means in said connecting means for regulating the effective movement of the piston in response to movement .of the pressure actuated means.

13. In combination with an oil flow line and a gas supply', a chemical tank, a pump housing, a pump in the pump housing, means connecting the tank with the pump, a diaphragm chamber in the pump housing, a diaphragm in said chamber, means operably connecting the diaphragm chamber with the pump, means connecting the gas supply with the diaphragm chamber, a valve in said gas supply connecting means'for controlling ow of gas to and from the diaphragm chamber, valve operating means actuated by the diaphragm lfor operating said valve to effect automatic operation of the pump and periodic injection of chemical into said oil flow line, means connecting the gas supply with the chemical tank to supply the chemical to the pump under pressure of said gas supply, and pressure reducing means in said gas supply connecting means for reducing the pressure of the gasdelivered to said' diaphragm chamber.

' GWYNNE. RAYMOND.

WALDEN W. MASON.