CN201511112U - Control system of centrifugal machine of ductile cast iron pipe - Google Patents
Control system of centrifugal machine of ductile cast iron pipe Download PDFInfo
- Publication number
- CN201511112U CN201511112U CN2009201876807U CN200920187680U CN201511112U CN 201511112 U CN201511112 U CN 201511112U CN 2009201876807 U CN2009201876807 U CN 2009201876807U CN 200920187680 U CN200920187680 U CN 200920187680U CN 201511112 U CN201511112 U CN 201511112U
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Abstract
The utility model discloses a control system of a centrifugal machine of a ductile cast iron pipe, which comprises a PLC (7), wherein a control device of a digital valve (1) is a digital valve controller (9), the digital valve controller (9) is provided with a digital servo valve, and the digital servo valve is driven by a stepping motor; digital valve controller (9) is provided with a coder (10) for coding the running speed and the position of the digital valve (1); a weighing sensor (5), the stepping motor for driving the digital servo valve and the coder (10) on the digital valve (1) are connected with the PLC (7) through a signal circuit. The technical scheme improvise the safety and the reliability of the system and the anti-jamming capability of the system, is especially suitable for the operation environment of the centrifugal machine and the existing maintenance level, can lead the equipment to work with zero debugging and zero maintenance, and guarantees the equipment to stably work for a long term.
Description
Technical field
The utility model belongs to the technical field that metallurgical industry is produced, and relates to ductile iron pipe production equipment and technology, and more particularly, the utility model relates to a kind of control system of ductile iron pipe centrifuge.
Background technology
Present ductile iron pipe production equipment is made up of three parts: running gate system, host machine part and pipe drawing device.
The ductile iron pipe production process is: after molten iron injected fan-shaped bag, main frame was gone to correspondence position and is prepared cast.Start and to turn over the bag oil cylinder and begin to turn over bag, fan-shapedly when just beginning turning be surrounded by one section idle stroke, when molten iron flows out, require fan-shaped bag at the uniform velocity to overturn.Molten iron longshore current concentrated flow begins to pour into a mould bellmouth to main frame, this moment, the main frame oil cylinder was elongated to maximum position, treat bellmouth water full after, the main frame uniform descending, the main frame oil cylinder is at the uniform velocity regained.
In this process, turn over the bag oil cylinder when at the uniform velocity turning to molten iron near socket always, turn over the bag cylinder and oppositely shrink, fan-shaped bag turns round about 2 degree, waits for cast next time.When molten iron watered to spigot, the main frame oil cylinder suspended, and continued descendingly after time-delay a period of time, and main frame withdraws from afterwards, and the tube drawing pincers are prepared tube drawing, and the beginning of weighing extracted cast tube by main frame oil cylinder elongation fast.
In a whole technology process, to turn over bag and adopt the proportional servo system to control to turn over speed packet and flip angle, main frame traveling process location and speed rely on common oil cylinder flexible.Weighing-up wave adopts the secondary table to show at operating desk, and the operative employee is with reference to show value and standard value difference, and rule of thumb manual adjustments is turned over and wrapped reversal rate and the main frame walking speed comes root Guan Chong under the balance.
Above-mentioned existing control mode is manually-operated.In whole process of production, play decisive role owing to turn over the accuracy of bag and traveling speed and location, weighing system also is directly connected to the quality problems of subsequent product simultaneously, therefore, only reaching empirical value in the above described manner operates and can not satisfy the existing processes requirement.
The utility model content
First problem to be solved in the utility model provides a kind of control system of ductile iron pipe centrifuge, its objective is to realize turning over bag and the digital valve speed of traveling and the accurately control automatically of position.
To achieve these goals, the technical scheme taked of the utility model is:
The control system of ductile iron pipe centrifuge provided by the utility model, the executing agency of described ductile iron pipe centrifuge comprises digital valve, be installed in and turn on bag and the main frame, take over the position LOAD CELLS is installed, the control system of described ductile iron pipe centrifuge is established PLC, the control device of described digital valve is a Digital Valve Controller, and described Digital Valve Controller is provided with digital servo valve, and this digital servo valve is driven by stepper motor; Described Digital Valve Controller is provided with the movement velocity of digital valve and the encoder of position; The stepper motor and the encoder on the digital valve of described LOAD CELLS, driving digital servo valve are connected with described PLC by signal line respectively.
For making the utility model more perfect, more detailed and concrete technical scheme below also further having proposed, to obtain best practical function, realize goal of the invention better, and improve novelty of the present utility model and creativeness:
Be provided with power module, CPU module, analog quantity input module, analog output module, switching input module and switching value output module among the described PLC.
Described PLC is connected with touch-screen by the MPI fieldbus.
Described LOAD CELLS is 4, transmits the mV signal to the weighing-up wave transmitter by holding wire respectively, and 4～20mA current signal is exported in described weighing-up wave transmitter conversion, is sent to the analog quantity input module of PLC by holding wire.
Described weighing-up wave transmitter output weighing-up wave and standard pipe heavily compare, and difference signal is flowed to described PLC, export described Digital Valve Controller to two groups of 4～20mA current forms after the PLC computing.
Second problem to be solved in the utility model provides the control method that control system adopted of above-described ductile iron pipe centrifuge, and the technical scheme of this method is:
Described LOAD CELLS is a weighing-up wave transmitter simultaneously, and weighing results is delivered to PLC7 with current forms, for the speed and the location of turning over bag and main frame provides reference data;
Utilize touch-screen to select cast;
After cast is selected to finish, import the cast quantity of equal specification cast, click " affirmation " key, realize operation automatically;
The full-automatic program of CPU storage inside reads the time for saving and improves control accuracy, and program process is as follows:
After every kind of cast is chosen, choose corresponding cast subprogram, call this program after the affirmation by compare instruction;
When many of a kind of specification casts are produced, put adapter in place signal as the command signal of caller again, provide counting to instruct simultaneously;
Whenever connect one and call a sub-subroutine by all means, adopt to add to instruct to finish once to add 1 counting;
The final count value of working as is identical with setting value, stops to produce after promptly equal specification cast quantity is finished and counts, and provides early warning signal to remind operating personnel simultaneously;
Finish on the touch-screen: in subprogram,, all be converted to floating number various pre-set parameters;
Weighing-up wave also is converted to floating number after entering PLC; After doing difference, carry out two groups of PID computings with the standard pipe anharmonic ratio;
Two groups of operation results are offered respectively turn over bag and digital valve setting value adds up;
Accumulation result is converted to analog quantity output 4～20mA Signal Matching data according to the PLC hardware requirement, and current signal is sent to Digital Valve Controller;
Simultaneously, after each weighing-up wave was waited to add up and finished, the signal automatic clear was so that the filling of group data down.
The utility model adopts technique scheme, the described digital Centrifugal Machine Control System speed control and the Position Control of complexity has originally become simple numerical pulse open loop control, thereby the security and the reliability of system have been improved greatly, and owing to there is not complicated closed-loop feedback arrangement, also improved the antijamming capability of system greatly, suitable especially centrifuge operating environment and existing maintenance levels, thereby improved the reliability of equipment greatly, and can accomplish that basically acyclic homologically trioial is tried and zero dimension is protected, the equipment that can guarantee is worked steadily in the long term.
Description of drawings
Below expressed content of each width of cloth accompanying drawing of this specification and the mark among the figure are briefly explained:
Fig. 1 is the ductile iron pipe centrifuge structural representation in the utility model;
Fig. 2 is the schematic top plan view of structure shown in Figure 1;
Fig. 3 is the control system schematic diagram in the utility model.
Be labeled as among the figure:
1, digital valve, 2, turn over bag, 3, main frame, 4, take over the position, 5, LOAD CELLS, 6, the weighing-up wave transmitter, 7, PLC, 8, touch-screen, 9, Digital Valve Controller, 10, encoder, 11, holding wire (sensor is to transmitter), 12, holding wire (transmitter is to PLC), 13, the MPI fieldbus, 14, holding wire (PLC to Digital Valve Controller), 15, holding wire (on-the-spot encoder is to Digital Valve Controller).
The specific embodiment
Contrast accompanying drawing below, by description to embodiment, to effect and operation principle, the manufacturing process of the mutual alignment between the shape of the specific embodiment of the present utility model such as related each member, structure, the each several part and annexation, each several part and manipulate method etc., be described in further detail, inventive concept of the present utility model, technical scheme had more complete, accurate and deep understanding to help those skilled in the art.
As Fig. 1, Fig. 2 and the expressed structure of the present utility model of Fig. 3, be a kind of ductile iron pipe centrifuge and control system thereof, this digital Centrifugal Machine Control System provided by the utility model comprises: instruction and detection system, Process Control System, executing agency's three parts.Described instruction and detection system comprise weighing system and touch-screen 8.The executing agency of described ductile iron pipe centrifuge comprises digital valve 1, is installed in to turn on bag 2 and the main frame 3, takes over position 4 LOAD CELLS 5 is installed.Described digital valve 1 comprises Digital Valve Controller and digital valve body.
Problem to be solved in the utility model provides a kind of high accuracy, full automatic Centrifugal Machine Control System, its objective is by PLC and provide speed and locator value accurately for the digital valve 1 of turning over bag 2 and traveling, simultaneously by detecting every Guan Chong, automatically the oil cylinder running status under regulating in the root pipe production process realizes accurately control automatically.
For this reason, the technical measures that provide of the utility model are:
As shown in Figure 3, the control system of ductile iron pipe centrifuge provided by the utility model is established PLC7, the control device of described digital valve 1 is a Digital Valve Controller 9, and described Digital Valve Controller 9 is provided with digital servo valve, and this digital servo valve is driven by stepper motor; Described Digital Valve Controller 9 is provided with the movement velocity of digital valve 1 and the encoder 10 of position; The stepper motor and the encoder 10 on the digital valve 1 of described LOAD CELLS 5, driving digital servo valve are connected with described PLC7 by signal line respectively.
Described Process Control System is PLC7; Instruction possesses the function of setting basic parameter, transmitting an on-the-spot signal with detection system; Process Control System receives instruction after the internal processes computing sends executing agency to.Whole process is simple to operation, and all state values and detected value are signal one time simultaneously, does not all need manual intervention in computing, the running.
As the expressed structure of the present utility model of Fig. 1 is digital centrifuge full-automatic control system, and the capital equipment that described system controlled is that centrifuge turns over bag 2 and main frame 3 interior two digital valve 1.Take over uniform four table scales in 4 places, position among Fig. 2 and retransmit sensor 5.Weighing-up wave transmitter 6, touch-screen 8 and Digital Valve Controller 9 all are installed on place, operating desk position in Fig. 3.On-the-spot installation encoder 10 operative employees only need to set the cast data in touch-screen 8 at every turn and output click acknowledgement key just can be carried out fully automatic operation.
Above-described digital valve 1 is highly integrated Hydraulic Elements, is installed on to turn on bag 2 and the main frame 3.Take over position 4 LOAD CELLS 5 is installed, sensor voltage signal is converted to standard 4～20mA current signal by weighing-up wave transmitter 6 delivers to PLC7.Each command signal that PLC7 receives is unified given by touch-screen 8.Digital Valve Controller 9 receives the current signal by PLC7 output 4～20mA, is converted to high-frequency pulse signal, digital valve 1 inner stepper motor received pulse signal and rotating, and this rotations drive digital servo valve also changes rectilinear motion into; Digital Valve Controller 9 is come realization speed and position feedback by collection site encoder 10 numerical value, thereby realizes accurate speed governing and location, reaches high accuracy control requirement.
The concrete exemplifying embodiment of control system of the present utility model is as follows respectively:
One, the formation of PLC:
Be provided with power module, CPU module, analog quantity input module, analog output module, switching input module and switching value output module among the PLC7 described in the utility model.
Two, being connected of PLC and Digital Valve Controller:
PLC7 described in the utility model is connected with Digital Valve Controller 9 by holding wire 14.
Three, being connected of PLC and touch-screen:
PLC7 described in the utility model is connected with touch-screen 8 by MPI fieldbus 13.
Described touch-screen 8 is all gathered the PLC7 internal signal, according to the corresponding input 1,2,3 of each centrifuge cast ..., click acknowledgement key.PLC7 transfers inside corresponding cast program, carries out fully automatic operation.
Four, being connected of on-the-spot encoder and Digital Valve Controller:
On-the-spot encoder described in the utility model is connected with Digital Valve Controller 9 by holding wire 15.
Five, the signal of LOAD CELLS transmission:
LOAD CELLS 5 described in the utility model is 4, transmit the mV signal to weighing-up wave transmitter 6 by holding wire 11 respectively, 4～20mA current signal is exported in described weighing-up wave transmitter 6 conversions, is sent to the analog quantity input module of PLC7 by holding wire 12.
Take over position 44 of LOAD CELLSs be set, by holding wire 11) send the mV signal to weighing-up wave transmitter 6.4～20mA current signal is exported in 6 conversions of weighing-up wave transmitter, is sent to the analog quantity input module of PLC7 by holding wire 12.
Six, the signal of weighing-up wave transmitter connects:
Weighing-up wave transmitter 6 output weighing-up waves described in the utility model and standard pipe heavily compare, and difference signal is flowed to described PLC7, export described Digital Valve Controller 9 to two groups of 4～20mA current forms after the PLC7 computing.
Weighing-up wave transmitter 6 output weighing-up waves and standard pipe heavily compare, and export difference to turn over bag 2 and main frame 3 travelings Digital Valve Controller (9) with two groups of 4～20mA current forms after the PLC7 computing.
Seven, the control method that control system adopted of the ductile iron pipe centrifuge that provides of the utility model, the technical scheme of this method is:
Described LOAD CELLS 5 is a weighing-up wave transmitter 6 simultaneously, and weighing results is delivered to PLC7 with current forms, for the speed and the location of turning over bag 2 and main frame 3 provides reference data;
Utilize touch-screen 8 to select cast;
After cast is selected to finish, import the cast quantity of equal specification cast, click " affirmation " key, realize operation automatically;
The full-automatic program of CPU7 storage inside reads the time for saving and improves control accuracy, and program process is as follows:
After every kind of cast is chosen, choose corresponding cast subprogram, call this program after the affirmation by compare instruction;
When many of a kind of specification casts are produced, put adapter in place signal as the command signal of caller again, provide counting to instruct simultaneously;
Whenever connect one and call a sub-subroutine by all means, adopt to add to instruct to finish once to add 1 counting;
The final count value of working as is identical with setting value, stops to produce after promptly equal specification cast quantity is finished and counts, and provides early warning signal to remind operating personnel simultaneously;
On touch-screen 8, finish: in subprogram,, all be converted to floating number various pre-set parameters;
Weighing-up wave also is converted to floating number after entering PLC7; After doing difference, carry out two groups of PID computings with the standard pipe anharmonic ratio;
Two groups of operation results are offered respectively turn over bag 2 and digital valve 1 setting value adds up;
Accumulation result is converted to analog quantity output 4～20mA Signal Matching data according to the PLC7 hardware requirement, and current signal is sent to digital valve 1 control appliance;
Simultaneously, after each weighing-up wave was waited to add up and finished, the signal automatic clear was so that the filling of group data down.
In described instruction and detection system, retransmit sensor 5 at four table scales of taking over position 4 and mate weighing-up wave transmitter 6 simultaneously, weighing results is delivered to PLC7 with current forms, for the speed and the location of turning over bag 2 and main frame 3 next time provides reference data.Touch-screen 8 possesses demonstration and operating function: each equipment running status and real time data all can onlinely show.Simultaneously, touch-screen 8 possesses the cast selection function, is handled easily, and various casts are corresponded to Arabic numerals, as the corresponding numeral 1 of DN80, the corresponding numeral 2 of DN100, the corresponding numeral 3 of DN125, and the like.After cast is selected to finish, import equal specification cast quantity (default value is 1) and click " affirmation " key realization operation automatically, also can finish the full-automatic process that cast racemosus of the same race is produced.Touch-screen 8 can reset the standard value of digital valve 1 speed, location and the various Guan Chong of each cast according to technological requirement, sets and carries out the back standard of upgrading after " setting check " key is clicked in the back that finishes.Touch-screen 8 possesses the automatic/hand translation function simultaneously.
The full-automatic program of described CPU7 storage inside reads the time for saving and improves control accuracy, and the programming detailed rules and regulations are as follows:
Every kind of cast is chosen the back and is chosen corresponding cast subprogram by comparing (CMP) instruction, calls this program after the affirmation.
When cast racemosus of the same race is produced, put adapter in place signal as the command signal of caller again, provide counting to instruct simultaneously.Whenever connect a tap and call a sub-subroutine, adopt to add (AND) instruction and finish and once add 1 counting.Finally after count value is identical with setting value (equal specification cast quantity), stop to produce.Provide early warning signal to remind operating personnel simultaneously.
For guaranteeing the accuracy of computing, in subprogram,, all be converted to floating number with various pre-set parameters (finishing in the touch-screen 8).Weighing-up wave also is converted to floating number after entering PLC7.After doing difference, carry out two groups of PID computings with the standard pipe anharmonic ratio.Two groups of operation results are offered respectively turn over bag 2 and traveling digital valve 1 setting value adds up.Accumulation result is converted to analog quantity output 4～20mA Signal Matching data according to the PLC7 hardware requirement, current signal is sent to the control appliance of digital valve 1.After simultaneously each weighing-up wave was waited to add up and finished, the signal automatic clear was so that the filling of group data down.
As executing agency, the control appliance of digital valve 1 receives PLC7 output 4～20mA signal, and current signal is converted to high-frequency pulse signal delivers to stepper motor in the oil cylinder.Because all elements all are contained in the oil cylinder, when stepper motor receives a pulse signal, oil cylinder just moves a fixing stroke (as 0.1mm), when the needs oil cylinder moves 10mm, then continuously to 100 pulses of digital cylinder output, when needs move 10mm 1 second, then output frequency is 100/ second, if when wishing to cover 10mm in 0.1 second, then output frequency gets 1000, by that analogy.
In conjunction with the accompanying drawings the utility model has been carried out exemplary description above; obviously the utility model specific implementation is not subjected to the restriction of aforesaid way; as long as adopted the improvement of the various unsubstantialities that method of the present utility model design and technical scheme carry out; or design of the present utility model and technical scheme are directly applied to other occasion without improving, all within protection domain of the present utility model.
Claims (5)
1. the control system of a ductile iron pipe centrifuge, the executing agency of described ductile iron pipe centrifuge comprises the digital valve (1) of control execution oil cylinder, be installed in and turn on bag (2) and the main frame (3), take over position (4) LOAD CELLS (5) is installed, it is characterized in that: the control system of described ductile iron pipe centrifuge is established PLC (7), the control device of described digital valve (1) is Digital Valve Controller (9), described Digital Valve Controller (9) is provided with digital servo valve, and this digital servo valve is driven by stepper motor; Described Digital Valve Controller (9) is provided with the movement velocity of digital valve (1) and the encoder (10) of position; The stepper motor and the encoder (10) on the digital valve (1) of described LOAD CELLS (5), driving digital servo valve are connected with described PLC (7) by signal line respectively.
2. according to the control system of the described ductile iron pipe centrifuge of claim 1, it is characterized in that: be provided with power module, CPU module, analog quantity input module, analog output module, switching input module and switching value output module among the described PLC (7).
3. according to the control system of the described ductile iron pipe centrifuge of claim 1, it is characterized in that: described PLC (7) is connected with touch-screen (8) by MPI fieldbus (13).
4. according to the control system of the described ductile iron pipe centrifuge of claim 1, it is characterized in that: described LOAD CELLS (5) is 4, transmit the mV signal to weighing-up wave transmitter (6) by holding wire (11) respectively, 4～20mA current signal is exported in described weighing-up wave transmitter (6) conversion, is sent to the analog quantity input module of PLC (7) by holding wire (12).
5. according to the control system of the described ductile iron pipe centrifuge of claim 1, it is characterized in that: described weighing-up wave transmitter (6) output weighing-up wave and standard pipe heavily compare, difference signal is flowed to described PLC (7), after PLC (7) computing, export described Digital Valve Controller (9) to two groups of 4～20mA current forms.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009201876807U CN201511112U (en) | 2009-09-21 | 2009-09-21 | Control system of centrifugal machine of ductile cast iron pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009201876807U CN201511112U (en) | 2009-09-21 | 2009-09-21 | Control system of centrifugal machine of ductile cast iron pipe |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201511112U true CN201511112U (en) | 2010-06-23 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2009201876807U Expired - Lifetime CN201511112U (en) | 2009-09-21 | 2009-09-21 | Control system of centrifugal machine of ductile cast iron pipe |
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| Country | Link |
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| CN (1) | CN201511112U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103273034A (en) * | 2013-05-16 | 2013-09-04 | 新兴河北工程技术有限公司 | Automatic control device of traveling speed of main engine of nodular cast iron pipe centrifugal machine |
| CN106597986A (en) * | 2017-01-23 | 2017-04-26 | 重庆师范大学 | PID-based double-stage pusher centrifuge control device and method |
-
2009
- 2009-09-21 CN CN2009201876807U patent/CN201511112U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103273034A (en) * | 2013-05-16 | 2013-09-04 | 新兴河北工程技术有限公司 | Automatic control device of traveling speed of main engine of nodular cast iron pipe centrifugal machine |
| CN106597986A (en) * | 2017-01-23 | 2017-04-26 | 重庆师范大学 | PID-based double-stage pusher centrifuge control device and method |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20100623 |
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| CX01 | Expiry of patent term |