CN104898724B - Automatic pH value control device for sulfide stress cracking resistance test, and control method thereof - Google Patents
Automatic pH value control device for sulfide stress cracking resistance test, and control method thereof Download PDFInfo
- Publication number
- CN104898724B CN104898724B CN201510317288.XA CN201510317288A CN104898724B CN 104898724 B CN104898724 B CN 104898724B CN 201510317288 A CN201510317288 A CN 201510317288A CN 104898724 B CN104898724 B CN 104898724B
- Authority
- CN
- China
- Prior art keywords
- value
- hydrochloric acid
- control unit
- unit plc
- test
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Abstract
The invention provides an automatic pH value control device for sulfide stress cracking resistance test, and a control method thereof. The automatic pH value control device comprises a control unit PLC and a pipeline which is used for communicating a hydrochloric acid container with a testing container. The pipeline is provided with a valve and a hydrochloric acid metering pump. One end of the pipeline extends into the inner part of the testing container. Furthermore the pipeline end in the testing container is provided with a liquid dispersing machine. The control unit PLC is connected with a mixing system, a pH meter and the hydrochloric acid metering pump. In the test process of the automatic pH value control device, hydrochloric acid can be added into the testing container through controlling of the control unit PLC, thereby controlling the pH value to a target value automatically, accurately and quickly. The liquid dispersing machine and the mixing system are used for quickly changing the pH value of a solution system in the testing container to a steady state. The automatic pH value control device is applied in the sulfide stress cracking resistance test of materials, thereby realizing no repeated opening and closing of the testing container, preventing hydrogen sulfide leakage, realizing safe operation and furthermore the stable pH value in the whole testing process can be ensured.
Description
Technical field
The present invention relates to material corrosion experimental test field is and in particular to a kind of resistance to SSC test pH value
Automaton and its control method.
Background technology
With continually developing of peracidity oil gas field, the hydrogen sulfide corrosion problem that oil field equipment is faced is increasingly serious.Its
In, sulfide stress cracking (SSC) (SSC) can make metal material that unexpected fracture occurs under relatively low working stress because of it in the short time,
Lead to major accident, so harm is maximum.Should for avoiding oil field equipment, during wet hydrogen sulfide environment military service, sulfide occurs
Power ftractures (SSC), need to carry out reasonable material and evaluation for sour environment.
At present, conventional sour environment selection standard is ISO 15156-2009《Oil and natural gas industry is in Accumulation of Hydrocarbon
H is contained in product2The material using under S environment》.The laboratory of carbon steel and low alloy steel anti-SSC performance is evaluated according to this standard
Test procedure, the sample of loading stress need to be positioned in particular solution environment and carry out immersion test.And define 2 kinds of solution rings
Border, a kind is conventional NACE solution A, and another a kind is 5% (mass fraction) NaCl+0.4% (mass fraction) CH3COONa, uses
Hydrochloric acid or NaOH are transferred to desired value pH value, and during guarantee test, pH value should be less than or equal to desired value.PH value can be controlled
System is in 0.1 pH value unit range.NACE solution A was once widely used in the middle of material anti-SSC performance evaluation, but this
Solution only specifies the effective pH value range of guarantee test it is impossible to the true Service Environment of simulator, is likely to result in actual selection not
Suitable, selection occurs and wastes or the no available phenomenon of suitable material.And the 2nd kind of method is based on FFP criterion, actual for oil field equipment
Service Environment, pH value during strict Control experiment, it is more conducive to select the material being suitable for used by scene.
But specify only the compound method of solution 2 in standard, be not directed to specific method of pH control and device.And should
Although solution is buffer solution, experimental period is up to 720 hours so that pH value still raises with the prolongation of soak time.
Conventional method is that manually periodically salt adding acid carries out pH value regulation, but the method has problems with：(1) the opening and closing test repeating
Container, is likely to result in the leakage of hydrogen sulfide, threatens experimenter's safety, or makes oxygen enter container, causes test failure.(2)
Because cannot be carried out stirring, hydrochloric acid can not diffuse to whole container rapidly, cause pH value cannot rapid and accurate determination, tone pitch occurs not
Accurate.(3) because solution used by each test is different, hydrochloric acid dosage is not fixed it is impossible to accurately carry out pH value control.(4) testing liquid
For being passed through the sour gas such as hydrogen sulfide in buffer solution, and process of the test always, hydrochloric acid dosage is wayward.(5) need special messenger 24
Hour on duty it is ensured that pH stable in whole process of the test.
Content of the invention
For solving the problems of the prior art, it is an object of the invention to a kind of resistance to SSC test pH value
Automaton and its control method, are automatically added to hydrochloric acid, precise control hydrochloric acid dosage, and are adding in achievable process of the test
Open stirring during hydrochloric acid, make the automatic accurate adjustment of solution ph and be rapidly achieved stable state.
For reaching above-mentioned purpose, the present invention adopts the following technical scheme that：
A kind of resistance to SSC test pH value automaton, including control unit PLC be used for connecting
Hydrochloric acid container and the pipeline of test chamber, described pipeline is provided with valve and hydrochloric acid dosing pump, and test is stretched in one end of pipeline
Inside container, and the pipe end being located within test chamber is provided with liquid distributor；It is additionally provided with stirring in test chamber
System and pH meter, control unit PLC is connected with stirring system, pH meter and hydrochloric acid dosing pump respectively.
Described hydrochloric acid dosing pump is arranged between valve and hydrochloric acid container.
Described valve is check valve.
The precision of described pH meter is 0.01.
Described hydrochloric acid dosing pump is micro pump.
Described stirring system is stirring rod.
The material of described stirring system and liquid distributor is politef.
A kind of resistance to SSC test as claimed in claim 1 control method of pH value automaton, bag
Include following steps：
Step one：Target setting pH value a0, mixing time t0And acid addition time interval t1(t0<t1)；In experiment with measuring container
Liquor capacity be VmL, the concentration of hydrochloric acid solution in hydrochloric acid container be Cmol/L；
Step 2：When actual measurement pH value is more than or equal to a0When+0.1, control unit PLC carries out following computing：V1=V (10-a0-
10-(a0+0.1))/C, then control unit PLC unlatching pH meter amount pump 3, add V into test chamber1/ 2mL hydrochloric acid, controls meanwhile
Unit PLC opens stirring system and is stirred；
Step 3：Reach acid addition time interval t1Afterwards, judge now to survey pH value a1Whether it is equal to a0If surveying pH value
a1Equal to a0, then complete pH value and adjust；If actual measurement pH value a1More than a0, then control unit PLC carry out following computing：V2=V (10-a0-10-a1)/C, then control unit PLC unlatching pH meter amount pump, add V into test chamber2/ 2mL hydrochloric acid, meanwhile, controls single
First PLC opens stirring system and is stirred；
Step 4：Repeat step three, until actual measurement pH value is target ph a0.
The speed of described stirring is 30～50 revs/min.
Compared with prior art, the device have the advantages that being：The present invention passes through setting connection hydrochloric acid container and examination
Test the pipeline of container, and setting valve and hydrochloric acid dosing pump on this pipeline, in process of the test, by control unit PLC
Control can add hydrochloric acid in test chamber, automatically, accurately and fast by pH value can control in desired value, be divided using liquid
Scattered device and stirring system, make the solution system pH value in test chamber be rapidly achieved stable state.This device is applied to material sulfur resistive
During compound stress cracking is evaluated, without the opening and closing test chamber repeating, it is to avoid the leakage of hydrogen sulfide, and safe operation, protect
Demonstrate,prove the effectiveness of test, ensure that pH stable in whole process of the test simultaneously.
Further, valve is check valve, it is to avoid the solution in testing liquid pours in down a chimney back in hydrochloric acid container.
Further, the precision of pH meter is 0.01, and hydrochloric acid dosing pump is micro pump such that it is able to molten in guarantee test container
The accuracy of liquid pH value.
Further, stirring system, pH meter are individually linked in test chamber, ensure that test chamber is being carried out
Sealing during sulfide stress cracking (SSC).
The present invention passes through first setting and passes through target ph a0, mixing time t0And acid addition time interval t1(t0<t1), Ran Houshi
When testing, according to the pH value of actual measurement, by control unit PLC logic control element, using the method for Approach by inchmeal, constantly to examination
Test addition hydrochloric acid in container, realize to buffering in test chamber and the pH value of saturation acidity gas solution system is accurately controlled automatically
System；And the present invention ensure that automatically being added in test chamber on demand of hydrochloric acid, and hydrochloric acid diffusion can be quickly completed, all
Matter, easy to operate, beneficial to realization, and can accurately control the addition of hydrochloric acid, pH stable in whole process of the test,
Thus ensure that the accuracy of test.
Further, mixing speed be 30～50 revs/min so that add hydrochloric acid, be passed through hydrogen sulfide while, it is to avoid
The generation of precipitation is it is ensured that sulfide stress cracking (SSC) test is normally carried out.
Brief description
Fig. 1 is the resistance to SSC test pH value automaton structural representation of the present invention；
Fig. 2 is the schematic flow sheet of resistance to SSC test pH value autocontrol method of the present invention；
In figure, 1- test chamber, 2-pH meter, 3- hydrochloric acid dosing pump, 4- control unit PLC, 5- stirring system, 6- liquid divide
Scattered device, 7- valve, 8- hydrochloric acid container.
Specific embodiment
The present invention is described in detail below in conjunction with the accompanying drawings.
Referring to Fig. 1, the resistance to SSC test pH value automaton of the present invention includes：Control unit
PLC with for connect hydrochloric acid container 8 and test chamber 1 and for into test chamber 1 add hydrochloric acid pipeline, on described pipeline
It is provided with valve 7 and hydrochloric acid dosing pump 3, and hydrochloric acid dosing pump 3 is arranged between valve 7 and hydrochloric acid container 8, one end of this pipeline
Stretch into inside test chamber 1, the pipe end within positioned at test chamber 1 is provided with liquid distributor 6, in test chamber 1 also
It is provided with stirring system 5 and pH meter 2, control unit PLC 4 is connected with stirring system 5, pH meter 2 and hydrochloric acid dosing pump 3 respectively
Connect.Stirring system 5 in the present invention is stirring rod.The material of stirring rod and liquid distributor 6 is nonmetallic materials, and such as poly- four
Fluorothene.
Described valve 7 is check valve, it is to avoid the solution in testing liquid 1 pours in down a chimney back in hydrochloric acid container.
The precision of described pH meter 2 is 0.01, and hydrochloric acid dosing pump 3 is micro pump such that it is able to solution in guarantee test container
The accuracy of pH value.
Described stirring system 5, pH meter 2 are individually linked in test chamber 1, ensure that the sealing of test chamber 1.
Referring to Fig. 2, resistance to SSC test pH value autocontrol method comprises the following steps：
Step one：Before test, target setting pH value a in control unit PLC0, mixing time t0, acid addition time interval t1
(t0<t1), and the liquor capacity in determination test container is concentration C mol/L of the hydrochloric acid solution in VmL and hydrochloric acid container.
Step 2：In test, real-time continuous monitoring is carried out to the testing liquid's pH value in test chamber by pH meter 2, when
The pH value of pH meter 2 display is more than or equal to a0When+0.1, control unit PLC, according to set parameter, calculates V1=V (10-a0-10-(a0+0.1))/C, and instruction is assigned to dosing pump 3, add V in test chamber 11/ 2mL hydrochloric acid；PH meter amount pump 3 is to test chamber
Middle addition V1While/2mL hydrochloric acid, control unit PLC assigns instruction, opens stirring system 5 and carries out low rate mixing；
Step 3：Reach acid addition time interval t1After arriving, judge now to survey pH value a1, if equal to a0If surveying pH
Value a1Equal to a0, then complete pH value and adjust；If actual measurement pH value a1More than a0, then control unit PLC carry out following computing：V2=V
(10-a0-10-a1)/C, then control unit PLC instruction is assigned to dosing pump 3, in test chamber 1 add V2/ 2mL hydrochloric acid；Meter
Amount pump 3 adds V in test chamber2While/2mL hydrochloric acid, control unit PLC assigns instruction, opens stirring system 5 and carries out slowly
Speed stirring；
Step 4：Reach acid addition time interval t1After arriving, judge now to survey pH value a2Whether it is equal to a0If surveying pH
Value a2Equal to a0, then complete pH value and adjust；If actual measurement pH value a2More than a0, then control unit PLC carry out following computing：V3=V
(10-a0-10-a2)/C, then control unit PLC instruction is assigned to dosing pump 3, in test chamber 1 add V3/ 2mL hydrochloric acid；Meter
Amount pump 3 adds V in test chamber3While/2mL hydrochloric acid, control unit PLC assigns instruction, opens stirring system 5 and carries out slowly
Speed stirring；
Step 5：Repeat step four, until actual measurement pH value is target ph a0, complete pH value and automatically adjust.
The test chamber adopting in the present invention is 10L, and the speed of stirring rod low rate mixing is 30～50 revs/min.Such
Mixing speed is while adding hydrochloric acid, be passed through hydrogen sulfide, it is to avoid the generation of precipitation is it is ensured that sulfide stress cracking (SSC) is tested just
Often carry out.
The present invention has the advantage that as follows：
(1) pass through PLC logic control element, using the method for Approach by inchmeal, realize to buffering and saturation sour gas is molten
The automatic precise control of pH value of liquid system；(2) adopt liquid distributor and low rate mixing system, so that solution system pH value is quickly reached
To stable state；(3) adopt check valve, it is to avoid testing liquid pours in down a chimney back in hydrochloric acid solution.
Claims (7)
1. a kind of resistance to SSC test with pH value automaton it is characterised in that include control unit PLC
(4) be used for connecting the pipeline of hydrochloric acid container (8) and test chamber (1), described pipeline is provided with valve (7) and hydrochloric acid metering
Pump (3), test chamber (1) inside is stretched in one end of pipeline, and the internal pipe end of test chamber (1) is provided with liquid
Disperser (6)；Be additionally provided with stirring system (5) and pH meter (2) in test chamber (1), control unit PLC (4) respectively with stirring
System (5), pH meter (2) and hydrochloric acid dosing pump (3) are connected；Described hydrochloric acid dosing pump (3) is arranged on valve (7) and is held with hydrochloric acid
Between device (8)；The precision of described pH meter (2) is 0.01.
2. resistance to SSC test according to claim 1 with pH value automaton it is characterised in that institute
Stating valve (7) is check valve.
3. resistance to SSC test according to claim 1 with pH value automaton it is characterised in that institute
Stating hydrochloric acid dosing pump (3) is micro pump.
4. resistance to SSC test according to claim 1 with pH value automaton it is characterised in that institute
Stating stirring system (5) is stirring rod.
5. resistance to SSC test according to claim 1 with pH value automaton it is characterised in that institute
State stirring system (5) and the material of liquid distributor (6) is politef.
6. a kind of based on the controlling party of pH value automaton of the resistance to SSC test described in claim 1
Method, comprises the following steps：
Step one：Target setting pH value a0, mixing time t0And acid addition time interval t1, t0<t1；Solution in experiment with measuring container
Volume is VmL, and the concentration of hydrochloric acid solution in hydrochloric acid container is Cmol/L；
Step 2：When actual measurement pH value is more than or equal to a0When+0.1, control unit PLC carries out following computing：V1=V (10-a0-10-(a0+0.1))/C, then control unit PLC unlatching hydrochloric acid dosing pump, add V into test chamber1/ 2mL hydrochloric acid, controls meanwhile
Unit PLC opens stirring system and is stirred；
Step 3：Reach acid addition time interval t1Afterwards, judge now to survey pH value a1Whether it is equal to a0If surveying pH value a1It is equal to
a0, then complete pH value and adjust；If actual measurement pH value a1More than a0, then control unit PLC carry out following computing：V2=V (10-a0-10-a1)/C, then control unit PLC unlatching hydrochloric acid dosing pump, add V into test chamber2/ 2mL hydrochloric acid, meanwhile, control unit
PLC opens stirring system and is stirred；
Step 4：Repeat step three, until actual measurement pH value is target ph a0.
7. the resistance to SSC test according to claim 6 control method of pH value automaton, institute
The speed stating stirring is 30～50 revs/min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510317288.XA CN104898724B (en) | 2015-06-10 | 2015-06-10 | Automatic pH value control device for sulfide stress cracking resistance test, and control method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510317288.XA CN104898724B (en) | 2015-06-10 | 2015-06-10 | Automatic pH value control device for sulfide stress cracking resistance test, and control method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104898724A CN104898724A (en) | 2015-09-09 |
| CN104898724B true CN104898724B (en) | 2017-02-22 |
Family
ID=54031434
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510317288.XA Active CN104898724B (en) | 2015-06-10 | 2015-06-10 | Automatic pH value control device for sulfide stress cracking resistance test, and control method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104898724B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108489886A (en) * | 2018-03-07 | 2018-09-04 | 中国石油天然气集团有限公司 | A kind of gas storage tube corrosion simulator and the analogy method based on the device |
| CN113252853A (en) * | 2021-06-15 | 2021-08-13 | 湖南普道医药技术有限公司 | Method for detecting acid resistance of antacid |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002250794A (en) * | 2000-12-21 | 2002-09-06 | Toshiba Corp | Chemical decontamination method |
| CN102392128A (en) * | 2011-12-11 | 2012-03-28 | 郴州市金贵银业股份有限公司 | Acid adding device with accurate and automatic pH value control function |
| CN103207141A (en) * | 2013-03-21 | 2013-07-17 | 宝鸡石油钢管有限责任公司 | Hydrogen sulfide resistant stress corrosion cracking and bending test device |
| CN104280331A (en) * | 2013-07-09 | 2015-01-14 | 中国石油天然气集团公司 | Experiment apparatus for constant-load stretching tests in normal-temperature normal-pressure hydrogen sulfide environment |
| CN104404525A (en) * | 2014-11-14 | 2015-03-11 | 中国海洋石油总公司 | Method and special-purpose preparation for preventing oil gas pipeline and equipment from being corroded |
| CN204790613U (en) * | 2015-06-10 | 2015-11-18 | 中国石油天然气集团公司 | Anti sulfide stress cracking is experimental with pH value automatic control device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9157141B2 (en) * | 2007-08-24 | 2015-10-13 | Schlumberger Technology Corporation | Conditioning ferrous alloys into cracking susceptible and fragmentable elements for use in a well |
-
2015
- 2015-06-10 CN CN201510317288.XA patent/CN104898724B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002250794A (en) * | 2000-12-21 | 2002-09-06 | Toshiba Corp | Chemical decontamination method |
| CN102392128A (en) * | 2011-12-11 | 2012-03-28 | 郴州市金贵银业股份有限公司 | Acid adding device with accurate and automatic pH value control function |
| CN103207141A (en) * | 2013-03-21 | 2013-07-17 | 宝鸡石油钢管有限责任公司 | Hydrogen sulfide resistant stress corrosion cracking and bending test device |
| CN104280331A (en) * | 2013-07-09 | 2015-01-14 | 中国石油天然气集团公司 | Experiment apparatus for constant-load stretching tests in normal-temperature normal-pressure hydrogen sulfide environment |
| CN104404525A (en) * | 2014-11-14 | 2015-03-11 | 中国海洋石油总公司 | Method and special-purpose preparation for preventing oil gas pipeline and equipment from being corroded |
| CN204790613U (en) * | 2015-06-10 | 2015-11-18 | 中国石油天然气集团公司 | Anti sulfide stress cracking is experimental with pH value automatic control device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104898724A (en) | 2015-09-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109668824A (en) | Simulate the high speed humidity corrosion loop experimental provision of natural gas line internal corrosion environment | |
| CN105067509B (en) | Crude oil storage tank corrosion monitor | |
| CN104865179B (en) | A kind of gathering line corrosion inhibiter film layer evaluation experimental device | |
| CN104898724B (en) | Automatic pH value control device for sulfide stress cracking resistance test, and control method thereof | |
| CN102798585B (en) | Large-size temperature-controllable automatic stirring sedimentation compaction test device and test method thereof | |
| CN101832906A (en) | Accelerated test method and device for simulating freshwater-seawater alternate environment | |
| CN109444236A (en) | A kind of pipeline erosion corrosion and electrochemical testing device | |
| CN104215571A (en) | Method for testing high-temperature and high-pressure corrosion rate of multi-phase medium | |
| CN104568734A (en) | System for monitoring metal corrosion behaviors in flowing corrosive medium | |
| CN101699282A (en) | Device for measuring acid/rock reaction dynamics parameters of acid liquid systems with different viscosities | |
| CN209117519U (en) | A kind of ammonium nitrate solution preparation system and its concentration detection apparatus | |
| RU2646943C1 (en) | Viscosity meter and methods of its use | |
| CN104950024A (en) | Device and method for measuring hydrogen diffusion coefficient | |
| CN209690097U (en) | A kind of recycle stream dynamic formula erosion corrosion test device | |
| CN212989132U (en) | Acid resistance performance detection device for coal mine filling material | |
| CN204790613U (en) | Anti sulfide stress cracking is experimental with pH value automatic control device | |
| CN205384271U (en) | Developments tubular anti -scaling agent rating of merit system | |
| CN103091242A (en) | System for automatic test on cathode disbonding resistance of anticorrosive coating of steel pipe | |
| CN204758458U (en) | Gathering line corrosion inhibitor rete evaluation test device | |
| CN203587481U (en) | High-pressure hydrogen sulfide testing device | |
| CN103162754B (en) | Liquid quality flow measuring apparatus | |
| CN203941237U (en) | A kind of dynamic oil water mixed liquid electric conductivity test device | |
| CN104034760A (en) | Multifunctional tin plate surface characteristic testing device and use method thereof | |
| CN208588656U (en) | A kind of pre- deoxygenation detection of corrosion test solution and chemicals dosing plant | |
| CN209280533U (en) | A kind of simulated high-pressure Multiphase Flow fluctuating corrosion of piping experimental provision |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |