WO2011126367A2 - Phase shift controller for a reciprocating pump system. - Google Patents
Phase shift controller for a reciprocating pump system. Download PDFInfo
- Publication number
- WO2011126367A2 WO2011126367A2 PCT/NL2011/050230 NL2011050230W WO2011126367A2 WO 2011126367 A2 WO2011126367 A2 WO 2011126367A2 NL 2011050230 W NL2011050230 W NL 2011050230W WO 2011126367 A2 WO2011126367 A2 WO 2011126367A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- pump
- phase shift
- phase
- control device
- shift control
- Prior art date
Links
- 230000010363 phase shift Effects 0.000 title claims abstract description 68
- 238000006073 displacement reaction Methods 0.000 claims abstract description 42
- 230000007246 mechanism Effects 0.000 claims description 4
- 238000000034 method Methods 0.000 claims description 4
- 230000009467 reduction Effects 0.000 claims description 3
- 230000010349 pulsation Effects 0.000 abstract description 15
- 239000012530 fluid Substances 0.000 description 9
- 239000002002 slurry Substances 0.000 description 9
- 229910052500 inorganic mineral Inorganic materials 0.000 description 7
- 239000011707 mineral Substances 0.000 description 7
- 238000005065 mining Methods 0.000 description 6
- 238000012545 processing Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 3
- 230000006872 improvement Effects 0.000 description 2
- 230000003993 interaction Effects 0.000 description 2
- 238000005086 pumping Methods 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B11/00—Equalisation of pulses, e.g. by use of air vessels; Counteracting cavitation
- F04B11/005—Equalisation of pulses, e.g. by use of air vessels; Counteracting cavitation using two or more pumping pistons
- F04B11/0075—Equalisation of pulses, e.g. by use of air vessels; Counteracting cavitation using two or more pumping pistons connected in series
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B23/00—Pumping installations or systems
- F04B23/04—Combinations of two or more pumps
- F04B23/06—Combinations of two or more pumps the pumps being all of reciprocating positive-displacement type
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B15/00—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts
- F04B15/02—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts the fluids being viscous or non-homogeneous
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
- F04B49/007—Installations or systems with two or more pumps or pump cylinders, wherein the flow-path through the stages can be changed, e.g. from series to parallel
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
- F04B49/20—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00 by changing the driving speed
Definitions
- This disclosure relates generally to pumps and more particularly to multiple reciprocating positive displacement pumps for handling mineral slurries.
- Reciprocating positive displacement pumps are used for pumping fluid against relatively high pressure, when compared to single stage centrifugal pumps, for example. Further characteristics of such positive displacement pumps include high efficiency and an accurate flow output, but a relatively low flow capacity when compared to centrifugal pumps.
- more positive displacement pumps can be arranged in parallel such that their suction and/or discharge connections are connected into a single suction and/or discharge line. This means that the sum flow of the individual pumps can meet the total flow requirements of the application.
- the combination of the individual pumps and the interconnecting suction and discharge lines forms a pump system.
- a displacement element such as a piston or plunger makes a reciprocating motion inside a cylinder liner enabling the positive displacement the fluid to be pumped.
- the reciprocating motion of the displacement element is generated by a mechanism which transfers the rotating motion of the pump drive into a reciprocating motion of the displacement element.
- this mechanism may include crankshaft, eccentric shaft, camshaft or cam disc mechanisms.
- crankshaft driven positive displacement pump In the following description only the embodiment of the crankshaft type are described, further referred to as a crankshaft driven positive displacement pump.
- figure 1 a schematic cross section of a 3-cylinder or triplex single acting crankshaft driven positive displacement pump is shown.
- the displacement element can directly displace the pumped fluid or displace an intermediate fluid which displaces a flexible displacement element which displaces the pumped fluid, such as an abrasive slurry.
- the disclosure applies to an embodiment of a positive displacement pump, but as the improvement is of particular interest to positive slurry pumps as described below, the embodiment using an intermediate fluid and flexible displacement as specifically shown in figure 1 .
- crankshaft-driven positive displacement pump A typical characteristic of the crankshaft-driven positive displacement pump is the non-constant reciprocating velocity of the displacement element. Crankshaft-driven positive displacement pumps therefore inherently generate a non-constant flow or flow pulsation each crankshaft revolution.
- FIG 2 a typical flow pulsation generated during one crankshaft revolution or pump cycle of a triplex single-acting positive displacement pump is shown. Depending on the hydraulic response of the connected system these flow pulsations can result in pressure pulsations in the pumped fluid which can result in vibration of the piping and its support structure through which the fluid is flowing, and the pressure pulsations can create an unbalanced load in the piping system.
- crankshaft-driven positive displacement pump When more than one crankshaft-driven positive displacement pump is connected to a single suction and/or discharge inlet or outlet, an interaction between the flow pulsations generated by the individual pumps can occur. This interaction can cancel out or increase the total level of flow and pressure pulsations in the pump system, again depending on the hydraulic response of the connected system. Also, hydraulic resonances present in the pump system can be excited by the flow pulsations generated by each individual pump.
- An important parameter which determines the total flow and pressure pulsation in a given pump system is the phase shift between the crankshafts of the individual pumps. Controlling this phase shift can therefore help in controlling the flow and pressure pulsation in a given pump system using crankshaft-driven positive displacement pumps.
- phase shift control also referred to as pump synchronization
- the phase shift control requires pumps equipped with variable speed drives (VSD) which can be used to adjust and maintain the phase shift between the pumps by speed adjustments of the individual drives.
- VSD variable speed drives
- the individual pump and/or their drives are equipped with a phase sensor which indicates the position of the pump cycle of the individual pump, further referred to as phase of the individual pump.
- phase information is then used by the phase shift calculator to calculate the phase shifts between the individual pumps, which then is used by the phase shift controller to adjust the speed of the individual pumps such that the phase shift is adjusted towards or maintained at the desired phase shift.
- one pump in the pump system is assigned as the master pump.
- This master pump follows the pump system speed reference set- point without any adjustments for phase shift control.
- the other pumps are assigned as slaves who have to follow the master pump.
- the phase shift controller calculates the phase difference between the master and each slave pump and generates a speed set-point for each individual slave pump which is based on the phase shift between the master and the individual slave pump, such that a the constant and desired phase shift between the master and slave pump is obtained and maintained.
- the system operator has to decide which pump is going to operate as the master pump before starting the pump system, after which the phase shift of the slave pumps with respect to the selected master pump is determined. This can result in complex master/slave and phase shift scheduling procedures which can also be dependent on the particular system.
- phase shift control is lost when the master pump trips or has to be shut down. Depending on the specific embodiment of the phase shift control, it may be required to shut down the complete pump system because the master and slave initialization might need to be re-initialized from start up.
- the reliability of the phase shift control for the complete pump system is thus dependant on the reliability of a single pump which is assigned as the master pump.
- Embodiments known and used in prior art are normally limited to three or four pumps per pump system, and for which the master/slave scheduling procedures are relatively easy. Furthermore the total flow rate of prior art pump systems with phase shift control are limited so that the system can still operate reliably because unbalanced loads generated by the pressure pulsations are relatively low and can still be acceptable in some applications.
- the present disclosure is focused on a solution for the described shortcomings of the phase shift control systems of the prior art crankshaft-driven positive displacement pumps.
- a real pump is used as a master in a master/slave control scheme for controlling the phase shift between the master and slave pump.
- the drawbacks included the complex master/slave scheduling procedures, the reduced reliability of the pump system as it depends on the reliability of a single master pump, and the reduced performance of the entire pump system in case of an unstable master pump operation.
- the present disclosure is of a pump system using multiple- reciprocating, positive displacement pumps which phase shift is controlled by a phase shift controller.
- the phase shift controller uses a virtual master pump inside the phase shift controller which is used as a phase reference against which the phase shifts of the individual pumps is calculated.
- the phase shift controller adjusts the speed reference set-point for the variable speed drives of the individual pumps such that a desired phase shift is obtained and maintained.
- the operation of multiple reciprocating pumps using phase shift control can significantly reduce the pressure pulsation levels in the pump system.
- the use of a virtual master pump eliminates master slave scheduling and increases system reliability and availability as is the operating of the phase control is not depending on the reliability of a real master pump as is the case in prior art phase shift controllers.
- the virtual master pump creates a phase reference signal within the phase shift controller based on a single pump system reference speed set-point just as a real master pump would do. All the real pumps in the pump system act as slaves in the phase shift controller. The phase of each individual pump is compared to the phase of the virtual master pump inside the controller which is then used as an input for the phase shift control.
- figure 4 a control flow diagram for the virtual master phase shift controller is shown.
- a virtual master pump can provide some operational improvements over the known prior art crankshaft-driven, positive displacement phase shift control systems.
- the slave pumps are always referenced against the same virtual master pump, hence no scheduling is required.
- the virtual master pump is considered to be available at all times as it does not require maintenance and has a much higher reliability than a real mechanical pump.
- the speed of the master pump is stable at all times since it is not influenced by the performance of a single master pump, which is especially useful when a positive displacement pump is used for pumping abrasive slurries in the mining and mineral processing industry.
- Figure 1 illustrates a schematic cross section of a prior art triplex single acting positive displacement pump, also showing an embodiment using an intermediate fluid and an additional flexible displacement element;
- Figure 2 illustrates a triplex single acting positive displacement pump flow pulsation of the prior art
- Figure 3 illustrates a prior art control flow diagram of reciprocating pump phase control with a master-slave control scheme using a real pump as master;
- Figure 4 illustrates a control flow diagram of reciprocating pump phase control with a master-slave control scheme using a virtual master, in accordance with the present disclosure.
- variable speed drive is not limited to a particular embodiment of the used variable speed drive, however the following embodiments are mentioned in particular:
- the sensor embodiment can generate absolute phase information on the pump cycle
- the sensor embodiment can generate phase information on the pump cycle based on the angular position of the main rotating component in the pump which transfers the rotating motion of pump drive into a reciprocating motion of the displacement elements, such as a crankshaft.
- the sensor embodiment can generate phase information on the pump cycle based on the angular position of the variable speed drive which can be directly coupled or coupled via speed reduction device with known reduction ratio to the main rotating component in the pump.
- the sensor embodiment can generate phase information on the pump cycle based on a single pulse generated at a predetermined position of the pump cycle.
- Phase shift controller The disclosure is not limited to a particular embodiment of the phase shift controller, however the following embodiments are mentioned in particular:
Abstract
Description
Claims
Priority Applications (9)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
RU2012147256/06A RU2012147256A (en) | 2010-04-07 | 2011-04-05 | PHASE SHIFT CONTROLLER FOR PISTON PUMP SYSTEM |
DE112011101269.1T DE112011101269B4 (en) | 2010-04-07 | 2011-04-05 | Phase shift control for an oscillating pump system |
US13/639,929 US20130078114A1 (en) | 2010-04-07 | 2011-04-05 | Phase shift controller for a reciprocating pump system |
CA2795538A CA2795538C (en) | 2010-04-07 | 2011-04-05 | Phase shift controller for a reciprocating pump system |
BR112012025571-1A BR112012025571B1 (en) | 2010-04-07 | 2011-04-05 | phase shift control device, pump system and method for controlling the individual speed of several alternative positive displacement pumps |
MX2012011512A MX2012011512A (en) | 2010-04-07 | 2011-04-05 | Phase shift controller for a reciprocating pump system. |
AU2011239051A AU2011239051B2 (en) | 2010-04-07 | 2011-04-05 | Phase shift controller for a reciprocating pump system. |
CN201180022244.4A CN102893028B (en) | 2010-04-07 | 2011-04-05 | Shift control device, pumping system and the method controlling multiple reciprocating pump each speed |
ZA2012/07493A ZA201207493B (en) | 2010-04-07 | 2012-10-05 | Phase shift controller for a reciprocating pump system |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US32160110P | 2010-04-07 | 2010-04-07 | |
US61/321,601 | 2010-04-07 | ||
NL2004979A NL2004979C2 (en) | 2010-04-07 | 2010-06-28 | Phase shift controller for a reciprocating pump system. |
NL2004979 | 2010-06-28 |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2011126367A2 true WO2011126367A2 (en) | 2011-10-13 |
WO2011126367A3 WO2011126367A3 (en) | 2015-07-02 |
Family
ID=43971690
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/NL2011/050230 WO2011126367A2 (en) | 2010-04-07 | 2011-04-05 | Phase shift controller for a reciprocating pump system. |
Country Status (11)
Country | Link |
---|---|
US (1) | US20130078114A1 (en) |
CN (1) | CN102893028B (en) |
AR (1) | AR080839A1 (en) |
AU (1) | AU2011239051B2 (en) |
CA (1) | CA2795538C (en) |
DE (1) | DE112011101269B4 (en) |
MX (1) | MX2012011512A (en) |
PE (1) | PE20130791A1 (en) |
RU (1) | RU2012147256A (en) |
TW (1) | TW201207236A (en) |
WO (1) | WO2011126367A2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016144161A1 (en) | 2015-03-09 | 2016-09-15 | Weir Minerals Netherlands B.V. | Hydraulic pump system for handling a slurry medium |
WO2019022593A1 (en) | 2017-07-27 | 2019-01-31 | Weir Minerals Netherlands B.V. | Pump system for handling a slurry medium |
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US9745840B2 (en) | 2012-11-16 | 2017-08-29 | Us Well Services Llc | Electric powered pump down |
US10407990B2 (en) | 2012-11-16 | 2019-09-10 | U.S. Well Services, LLC | Slide out pump stand for hydraulic fracturing equipment |
US9995218B2 (en) | 2012-11-16 | 2018-06-12 | U.S. Well Services, LLC | Turbine chilling for oil field power generation |
US11449018B2 (en) | 2012-11-16 | 2022-09-20 | U.S. Well Services, LLC | System and method for parallel power and blackout protection for electric powered hydraulic fracturing |
US9893500B2 (en) | 2012-11-16 | 2018-02-13 | U.S. Well Services, LLC | Switchgear load sharing for oil field equipment |
US11476781B2 (en) | 2012-11-16 | 2022-10-18 | U.S. Well Services, LLC | Wireline power supply during electric powered fracturing operations |
US10232332B2 (en) | 2012-11-16 | 2019-03-19 | U.S. Well Services, Inc. | Independent control of auger and hopper assembly in electric blender system |
US11149725B2 (en) | 2016-01-20 | 2021-10-19 | Weir Minerals Netherlands B.V. | Hydraulic pump system for handling a slurry medium |
RU2749519C2 (en) * | 2016-09-16 | 2021-06-11 | Роберт Бош Гмбх | Rotary electrohydraulic actuator |
US10656669B2 (en) | 2017-04-28 | 2020-05-19 | Graco Minnesota Inc. | Trigger guard and pendant for a portable hydraulic power unit |
CA3084596A1 (en) | 2017-12-05 | 2019-06-13 | U.S. Well Services, LLC | Multi-plunger pumps and associated drive systems |
US10648311B2 (en) | 2017-12-05 | 2020-05-12 | U.S. Well Services, LLC | High horsepower pumping configuration for an electric hydraulic fracturing system |
CN110894826B (en) * | 2018-09-13 | 2021-10-19 | 诺沃皮尼奥内技术股份有限公司 | Method for reducing pulsation level in a multi-compressor installation using reciprocating compressors |
WO2020056258A1 (en) | 2018-09-14 | 2020-03-19 | U.S. Well Services, LLC | Riser assist for wellsites |
US11578577B2 (en) | 2019-03-20 | 2023-02-14 | U.S. Well Services, LLC | Oversized switchgear trailer for electric hydraulic fracturing |
CA3139970A1 (en) | 2019-05-13 | 2020-11-19 | U.S. Well Services, LLC | Encoderless vector control for vfd in hydraulic fracturing applications |
CA3143050A1 (en) | 2019-06-10 | 2020-12-17 | U.S. Well Services, LLC | Integrated fuel gas heater for mobile fuel conditioning equipment |
US11459863B2 (en) | 2019-10-03 | 2022-10-04 | U.S. Well Services, LLC | Electric powered hydraulic fracturing pump system with single electric powered multi-plunger fracturing pump |
USD977426S1 (en) | 2019-12-13 | 2023-02-07 | Graco Minnesota Inc. | Hydraulic power pack |
CN112727752B (en) * | 2020-12-28 | 2022-10-14 | 广东拓斯达科技股份有限公司 | Multi-pump confluence flow pulsation eliminating method and device |
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2011
- 2011-04-05 PE PE2012001999A patent/PE20130791A1/en active IP Right Grant
- 2011-04-05 WO PCT/NL2011/050230 patent/WO2011126367A2/en active Application Filing
- 2011-04-05 US US13/639,929 patent/US20130078114A1/en not_active Abandoned
- 2011-04-05 CA CA2795538A patent/CA2795538C/en active Active
- 2011-04-05 DE DE112011101269.1T patent/DE112011101269B4/en active Active
- 2011-04-05 RU RU2012147256/06A patent/RU2012147256A/en not_active Application Discontinuation
- 2011-04-05 MX MX2012011512A patent/MX2012011512A/en unknown
- 2011-04-05 AU AU2011239051A patent/AU2011239051B2/en active Active
- 2011-04-05 CN CN201180022244.4A patent/CN102893028B/en active Active
- 2011-04-06 TW TW100111875A patent/TW201207236A/en unknown
- 2011-04-07 AR ARP110101161A patent/AR080839A1/en active IP Right Grant
Non-Patent Citations (1)
Title |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016144161A1 (en) | 2015-03-09 | 2016-09-15 | Weir Minerals Netherlands B.V. | Hydraulic pump system for handling a slurry medium |
AU2016229643B2 (en) * | 2015-03-09 | 2020-10-01 | Weir Minerals Netherlands B.V. | Hydraulic pump system for handling a slurry medium |
WO2019022593A1 (en) | 2017-07-27 | 2019-01-31 | Weir Minerals Netherlands B.V. | Pump system for handling a slurry medium |
Also Published As
Publication number | Publication date |
---|---|
AU2011239051B2 (en) | 2015-12-24 |
WO2011126367A3 (en) | 2015-07-02 |
MX2012011512A (en) | 2012-11-29 |
CN102893028A (en) | 2013-01-23 |
CN102893028B (en) | 2016-09-28 |
RU2012147256A (en) | 2014-05-27 |
AU2011239051A1 (en) | 2012-11-01 |
PE20130791A1 (en) | 2013-07-25 |
CA2795538A1 (en) | 2011-10-13 |
CA2795538C (en) | 2018-02-20 |
AR080839A1 (en) | 2012-05-09 |
US20130078114A1 (en) | 2013-03-28 |
DE112011101269T5 (en) | 2013-05-02 |
DE112011101269B4 (en) | 2021-05-06 |
TW201207236A (en) | 2012-02-16 |
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