US2619037A - Control system for hydraulic apparatus - Google Patents

Description

Nov. 25, 1952 w. J. F. O'CONNOR ETAL CONTROL SYSTEM FOR HYDRAULIC APPARATUS Filed Dec. 5, 1950 {NVENTORS Zara/2117080072011 Fran/t riJZowerz, J1:

Patented Nov. 25, 195 2 iUJNIiTIZED :STATII s CONTROL SYSTEM FORA'HYDRAULIC "APPARATUS v Ward JOGomior and Frank Ai Rowen, Jr.,

: Bayonne, N;J., assignorwtm'llhe hummus Gompany; New.-York; N. Y.,-'-1ai;'=corporation ofmDelaware This invention 'relates '-to control of the opera- I tion of hydraulic appara-tus capable of use in; a variety or services. *An example is the removal ofa hard deposit of coke -from' a coking drum. "-"In such ser-viceit -is common 'practice to use '-'-downwa1"dly directed hydraulic jets to first drill a central passagethroughdhe coke deposit and then use jets directed' laterally-outward from -*said passage'to' cutthe coke' into layers to' facilitate its dislodgement and removal through the ""lower end of the drumf For effective operation of the, jets; hydraulic app iratus capable ofdelivering water "at a pressure of approximately-- 1-500 -"lbs."--per"sq.- in: is-required. In the' operation of the apparatusyvariations" in pressure and changes 'in direction therofsuch as occur in the-start- -ing"and stoppingof the delivery to the jets cause severe shock' and strain upon the pump and the "piping-of theapparatus. "The-present invention *"is"concerned"particularlywith control of the-operation of the apparatus *in a-manner-to eliminate "i sush shock.

Important objectsof theinvention are; topro- *-'vide an improved controlsystem "for' hydraulic apparatus devised 'to eliminate injurious shock m the operation thereof rtoprbvide' such asystem" capable of accomplishingits'f purpose" with minimum attention from the operator ;"'-to provide aisystem responsive to one" setting of a single 'switch d'evice to "cause starting'and build-up of the hydraulic d'elivery'by the" apparatus-without ""shock' and responsive to "another setting or the switch device to cause the apparatus to stop deliverywith'out "shock; and" toprovide such a 'sy'stem"with' -efficient pneumatically operable mechanism responsive to the settings of i the ":swit'chdevice to effecti'said" control of the appa- "Tatus.

TFurther' obj ects" andi'advantages of the invention"Wilfappearfrom the "following description taken in" connection with "the accompanying ""'draiwing.

I "IIn'ithe drawing: Fig." 1 is view: partly dia'grammaticgshowlng the improved control system; operatively connect- "t""edtofhydraulie:apparatus?employed for a' de- "decking". operation.

1 Figi2 is" a'view, partlyidiagrammatic; eta-"porftion of the control system" with the-switch adijiisted to 'stop'hydr'aulic" delivery by the apparatus.

"Accordingrtotheinvention, the normal operai tiono'tith'e'hydraulicfapparatus is under the con- "ftiol:'ot'.a "single air"'switch"which is settablgto eitherioi' two positions for" starting-or stopping -idelivery' o'f hydraulic.v pressure "by the. apparatus. ""For'starting delivery'by'theapparatustheswitch 2 'iss'et in 'one 2'. of said positions and;- rinairesponse to said setting, pneumatically; operable: mechanism is actuated to 'doxthree things namely, -open v.av -valve -in the 'deliver'y line of the-pump, close a walve in A a =by-pass "lineithrough :which -lthecde- 7 livery' line is connected to the. suction line: of the '-pump', and 1 also' cause increase of: the rate of operation'ot the pump. Inresponseito the other setting of the switch the pneumatic mechanism is actuated to cause opening of saidby-passvalve, reduction- I of the s'peed' of the pump and closing I of the valve in the' delivery line. 'ThIOUgh -SUOh =control injurious-"shock is avoided "inAi-both V the starting and'stoppingof the delivery.

In Fig. 1 the improved control system is shown *as operatively. connected: to ihydraulic apparatus *for- "delivery i of water under high pressure to a jet device employed in a decokingoperation; The apparatus' 'includes 1 a pump I driven by a steam turbine Z h'avinga hydraulic governor; indicated siat 3. 'A hydraulic pipe 4 leads toi the governor 1 and-has a: valve 5. delivery pipe 6 leads from the pump and hasa valve'. 1.: :Beyond saidxvalve thepipe -6 is in delivery eonnection(withajet'ide- 25 :vice J 'through the usual rigging-which: enables iilowering and: raising of the: device through; a coke:drum-i D. I The rigging islomitted from vllthe :vridi'awingpto simplify fthe'il-lustration. A=by lpass 1 conduit iormed: of pipe: sections 8': connected -by an angle valve 'il; leads from the delivery-pipe, at--a point between" the-pump and' the valve 'L to ia -tank l 0; The su-ctionorchargeline l l oi'dzhe "pump'--' leads*fromth bottom of -saidtank to the --pump inlet. A water make-up conduit line fla' le'ads to the" tank.

'The control "system includes a; manually operable'air switch I 2- mounted" for shiftingof one end thereof between' positions A and' B. "The fswitch may be mounted in a positionadjacent 40- the 'top" of -the coking drum for convenient oper- 'ation. 1 It is shown; however; displaced from said i i position -for convenient illustration. air "supply li-ne l 3" leads to 'the- -switchposition--B and has a-manually setta-blepressure regulating'valve "H. "'An air line 15 leads"- from 'the' switch" to pneumatic mechanism for causing operation '-of thehydraulimvalves 5, '1 and 9. "Diaphragm 'motors" l6, '|1 'and I8 areoperatively connected to the valves 5; 1 and-' 9 respectively;and* are'op- 5Q-erable in"responseto *theswitch settings. Motor I 6" is conn'ected -by an'" air line I 9 to the line '1 5 whichleadsirom the" switch. Said linel5-also leads-toi a four-way' valve device 20. This device "includes-a" plunger type valve' 2 lreciprocable' to 'control air flow through two spaced-"ports 22 and-'ziiinthe valve'casingand" diaphragm motors Each of the motors I1 and I8 which operate the valves 1 and 9 respectively, has chambers at opposite sides of its diaphragm. An air line 30 leads from the port 22 of the four-way valve device 20 to the inner diaphragm chamber of motor H. A branch line 3| leads from line 30 to the outer diaphragm chamber of motor l8. Another air line 32 leads from port 23 of the four-way valve device to the inner diaphragm chamber of the motor l8, and a branch 33 of line 32 leads to the outer diaphragm chamber of motor l1.

Provision is made for stopping the turbine 2 in an emergency. For that purpose, a solenoid device 34 is operatively connected to a valve device 35 for controlling admission of steam from the steam line 36 to the turbine. The line 35 also has a manually operable valve 31. The circuit 33 of the solenoid has a push-button switch 39 located adjacent the air switch l2 for convenient operation,

air gauge device 40 is associated with the air switch |2. This device has a dial and two pointers 4| and. The pointer 4| is movable in response to pressure variations in the line l and the pointer 42 is movable in response to pressure variations in the line l3.

Preparatory to operating the apparatus, the air line I3 is supplied with air at a pressure of, say lbs. p. s. i. g., and the reducing valve I4 is adjusted to reduce said pressure to adesired loading of say 15 lbs. p. s. i. g. Air pressure at, say 35 lbs. p. s. i. g., is supplied to the line 26 leading to the four-way valve device 29, and'the reducing valve 29 reduces the pressure going to the diaphragm motor 25, to, say 5 lbs. p. s. i. g. Then, with the valve 31 of the steam supply line 36 to the turbine closed, the air switch |2 is set in the position indicated at A which may-be identified as the Minimum position. Fig.2 shows the switch in thisposition. In this position the switch registers with a vent V to atmosphere and the air escapes from above the diaphragm of,

motor 24 through the line l5, the switch and; said vent. The air pressure beneath the diaphragm of motor then forces the diaphragm and the valve 2| upward with reference to the drawing. In its elevated position the valve admits pres- 1 sure from the line 26, through the port 23 and the lines 32 and 33- to the inner chamber of the motor l8 and the outer chamber of motor ll. Simultaneously, the valve 2| vents to'atmosphere the outer chamber of motor |8-and the inner chamber of motor I! through the lines 3|, 30,

the valve port 22 and past the upper portion of valve 2| to atmosphere. Thereby,- the hydraulic by-pass valve 9 is opened and the delivery valve "l isclosed. When the air switch is in the position-shown in Fig. 2, air pressure beneath the diaphragm of the motor i6 escapes through the line I9, the line-|5, theair switch l2 and the vent The valve 5 is then operated toward closed 4 air switch I2 is set in the B position, as shown in Fig. 1. This position may be designated the Maximum position. Air from the line I3 is then admitted through the switch l2, and the line l5 to the upperside of the diaphragm of the motor 24. Thereby, the diaphragm and the valve 2| are forced downward against the resistance of the inferior pressure beneath the diaphragm of the motor 25. In its depressed position, the valve 2| exhausts to atmosphere the pressure within the outer diaphragm chamber of the motor ll, through the lines 33 and 32, the port 23 and the lower portion of the valve casing. The inner diaphragm chamber of motor I8 is also vented to atmosphere through the line 32. At the same time, pressure from the air supply line 2'6 is admitted through the port 22 and the lines 30 and 3| to the inner diaphragm chamber of motor I1 and the outer diaphragm chamber of motor l8, to cause opening of the hydraulic delivery valve 1 and closing of the by-pass valve 9. In its said Maximum position the air switch also admits pressure from the line |3 through the switch, the line l5 and the line I9 to the under side of the diaphragm of the governor valve motor 5. Thereby, the valve 5 is opened to increase the speed of the turbine and obtain th required working delivery by the pump through 'the line 8 to the jet device J. i

In order to stop delivery by the hydraulic apparatus it is merely required that the air switch 12 be shifted back to the Minimum position. The pneumatic control system then responds to cause opening of the by-pass valve 9, closing of the delivery valve 1 and'operation of the governorvalve 5 to reduce the speed of the turbine and the rate of operation of the pump In the intervals between decoking operations the valve 5 may reducethe pump delivery to one-third of the working delivery and the reduced delivery is by-passed to the pump inlet. Thereby, the load upon the pump during said intervals is reduced,

with a reduction in discharge pressure from say 1500 lbs. to 175 lbs. per sq. in.

' quickly by pressing the push-button switch 39 to close the circuit of the solenoid 34 and cause operation of the device 35 to stop delivery of steam to. the turbine 2.

.The delivery valve 1 is designed for closure mainly by hydraulic pressure within the delivery line 6 when the diaphragm motor IT is conditioned by the setting of the air switch 2 for closure of the valve. Also, the angle valve-9 is designed and piped for closure against the'stream through the by-pass 8. This is contrary toprior practice and produces good results. The arrangement of the valve according to prior practice has been found to cause cavitation, serious erosion and hammering. These faultsareminimized by the reversed arrangement. I U

- The invention .eliminates injurious shock in the operation of the hydraulic apparatus. and

g greatly facilitates control of. the operation By mere setting of asingle air switch in its .Maximum position '-for. hydraulic. delivery the delivery valve 1. is caused to open, the by-pass valve 8 is caused to-close and. the rate of deliveryis caused to increase. Another setting of the air switch causes opening of the by-pass valve, reduction in gentle operation of the hydraulic apparatus is obtained and injurious shock is eliminated.

While the invention is disclosed as employed in connection with decoking apparatus it may be employed advantageously in other services requiring high pressure hydraulic delivery. It will of course be understood that the present disclosure of the invention is merely illustrative and in nowise limiting and that the invention comprehends such modifications as will fall within the scope of the following claims.

We claim:

1. A pneumatic system for controlling the oper ation of hydraulic apparatus of a type including a pump, a motor for driving same, means operable to control the speed of said motor, a charge conduit leading to the pump inlet, a delivery conduit leading from the pump outlet and having a valve, and a by-pass conduit connection leading from said delivery conduit, at a point between said valve and the pump, to the pump inlet and having a valve, said pneumatic system comprising an air switch connected to a compressed air source and settable selectively at a low speed position or a high speed position, pneumatically operable devices operatively connected to said switch and operatively associated respectively, with said two valves and said motor speed control means, and responsive to the low speed setting of the switch to cause opening of the by-pass valve, closing of the delivery conduit valve and reduction of the motor speed, said devices being responsive to the high-speed setting of the switch to cause opening of the delivery conduit valve, closing of the by-pass valve and increase of the motor speed.

2. A fluid pressure operated system for controlling operation of hydraulic apparatus of a type including a pump, a motor for driving same, means operable to control the speed of said motor, a charge conduit leading to the pump inlet, a delivery conduit leading from the pump outlet and having a valve, and a by-pass conduit connection leading from said delivery conduit, at a point between said valve and the pump, to the pump inlet, and having a valve, said control system comprising a settable device, and mechanism operable by fluid pressure under control of said device and responsive to a setting thereof to cause opening of said by-pass valve, closing of said delivery conduit valve and operation of said motor speed control means to cause low speed operation of the motor.

3. A fluid pressure operated system for controlling operation of hydraulic apparatus of a type including a pump, a motor for driving same, means operable to control the speed of said motor, a charge conduit leading to the pump inlet and a delivery conduit leading from the pump outlet and having a valve, said control system comprising a fluid pressure switch settable selec- 0 Number tively at a low-speed position or a high-speed position, and mechanism operable by fluid pressure under control of said switch and responsive to the low-speed setting of the switch to cause closing of said valve and operation of said motor speed control means to reduce the motor speed, and responsive to the high-speed setting of the switch to cause opening of said valve and operation of the motor speed control means to increase the motor speed.

4. A system for controlling the operation of hydraulic apparatus including a pump, a motor for driving same, means operable to control the speed of said motor, a charge conduit leading to the pump inlet, a delivery conduit leading from the pump outlet and a by-pass conduit connection leading from said delivery conduit, at a point between said valve and the pump, to the pump inlet and having a valve, said control system comprising a switch settable selectively at a low-speed position or a high-speed position, and mechanism responsive to the low speed setting of said switch to cause opening of said bypass valve, closing of said delivery conduit valve and operation of said speed control means to reduce the motor speed, said mechanism being responsive also to the high speed setting of the switch to cause opening of the delivery conduit valve, closing of the by-pass valve and operation of the speed control means to increase the motor speed.

5. A system for controlling the operation of hydraulic apparatus including a pump, a motor for driving same, means operable to control the speed of said motor, a charge conduit leading to the pump inlet, a delivery conduit leading from the pump outlet and having a valve, and a bypass conduit connection leading from said delivery conduit, at a point between said valve and the pump, to the pump inlet, and having a valve, said control system comprising a manually operable control device, and mechanism responsive to one operation of said device to cause opening of said by-pass valve, closing of said delivery conduit valve and operation of said speed control means to reduce the motor speed, said mechanism being responsive also to another operation of said device to cause opening of the delivery conduit valve, closing of the by-pass valve and operation of the speed control means to increase the motor speed.

WARD J. F. O'CONNOR. FRANK A. BOWEN, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date 2,212,833 Huber Aug. 27, 194p

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