CN105092974B - Permanent-magnet material resistivity is with temperature and the measuring method of pressure change - Google Patents
Permanent-magnet material resistivity is with temperature and the measuring method of pressure change Download PDFInfo
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- CN105092974B CN105092974B CN201510566608.5A CN201510566608A CN105092974B CN 105092974 B CN105092974 B CN 105092974B CN 201510566608 A CN201510566608 A CN 201510566608A CN 105092974 B CN105092974 B CN 105092974B
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Abstract
Permanent-magnet material resistivity is with temperature and the measuring method of pressure change.The present invention relates to a kind of permanent-magnet material resistivity with temperature and the measuring method of pressure change.1. the resistance value and record of cylindrical permanent magnet sample under normal temperature and pressure are measured first, cylindrical permanent magnet sample is fixed on the insulating material again, it is put into high pressure sealing bucket, afterwards, it is closely wound heating cable in the outer surface of high pressure sealing bucket or is directly placed into pressure-resistant high-power electric heater in high pressure sealing bucket.2. heating cable or high-power electric heater are connected into AC power, adjust the output voltage of AC power, observe the temperature value in the high pressure sealing bucket that temperature sensor is shown at any time using high pressure sealing temperature within the barrel sensor probe is loaded, the temperature value is kept into for a period of time after temperature value needed for reaching, is starting measurement.The present invention is used for permanent-magnet material resistivity with temperature and the measuring method of pressure change.
Description
Technical field
The present invention relates to a kind of permanent-magnet material resistivity with temperature and the measuring method of pressure change.
Background technology
With the continuous increase of expanding economy and the mankind for petroleum-based energy demand, for petroleum resources exploitation just
Gradually develop to deep-seated oil gas field, with the continuous intensification of drilling depth, inevitably run into HTHP etc. exceedingly odious
Environment, as performing and the magneto of functional part will also be tested by extreme environment, primary is exactly institute among these
With the performance change situation of material, wherein just include the resistivity of permanent-magnet material to temperature and the situation of change of pressure, therefore it is right
Temperature and the situation of change of pressure are just particularly important in the permanent-magnet material resistivity being operated in Oil/gas Well, are this
Invention is used for measuring method of the permanent-magnet material resistivity with pressure change there is provided a kind of, and this also provides necessity for designer
Performance parameter.
The content of the invention
It is an object of the invention to provide a kind of permanent magnet sample resistivity that can very easily measure with temperature and pressure
Situation of change, and this method has very high precision, temperature proposed by the present invention and the common implementation method of pressure can be applied
In the detection of different materials, the permanent-magnet material resistivity having broad application prospects with temperature and pressure change measurement side
Method.
Above-mentioned purpose is realized by following technical scheme：
A kind of permanent-magnet material resistivity is with temperature and the measuring method of pressure change, and measurement permanent-magnet material resistivity is with temperature
And the step of pressure change is as follows：
1. the resistance value and record of cylindrical permanent magnet sample under normal temperature and pressure are measured first, then cylindrical permanent magnet is tried
Sample is fixed on the insulating material, is put into high pressure sealing bucket, afterwards, and heating cable is closely wound in the outer surface of high pressure sealing bucket
Or it is directly placed into pressure-resistant high-power electric heater in high pressure sealing bucket.
2. heating cable or high-power electric heater are connected into AC power, adjusts the output voltage of AC power, utilized
Load high pressure sealing temperature within the barrel sensor probe to observe the temperature value in the high pressure sealing bucket that temperature sensor is shown at any time,
The temperature value is kept at least 30 minutes after temperature value needed for reaching, and records temperature value now, then starts measurement.
3. after the temperature of cylindrical permanent magnet sample is up to standard, the compression pump being connected with high pressure sealing bucket is adjusted, it is slow to increase
Increase the pressure value shown on the pressure value shown on the pressure value in means of press seals bucket, observation pressure sensor, pressure sensor
Accuracy is greater than the value shown by the pressure gauge on compression pump, and closer to the actual value in high pressure sealing bucket.
4. the pressure value shown by record pressure sensor, and the resistance value R of cylindrical permanent magnet sample that measurement is obtained,
And calculate the permanent magnet sample resistivity of cylindrical permanent magnet sample different pressures at such a temperature：
Formula one
In formula, S is the cross-sectional area of cylindrical permanent magnet sample；For the distance between voltage detecting end.
5. repeat step 1.~step 4., the cylindrical permanent magnet sample under measurement different temperatures corresponding to different pressure
Resistance value R, and calculate corresponding permanent magnet sample electricalresistivityρ.
Described permanent-magnet material resistivity is with temperature and the measuring method of pressure change, first in cylindrical permanent magnet sample
Four different positions of upper selection, four positions of the lead-out wire of resistance measuring instrument and this are in contact, cylindrical permanent magnet sample
Outermost two positions are that two positions on the inside of galvanic contact end, cylindrical permanent magnet sample are voltage detecting end, then
The resistance R of cylindrical permanent magnet sample can be directly obtained by resistance measuring instrument, the cylindrical permanent magnet obtained according to measurement
Sample resistance R, calculates the resistivity for obtaining cylindrical permanent magnet sampleFor：
In formula, S is the cross-sectional area of cylindrical permanent magnet sample；For the distance between voltage detecting end.
Described permanent-magnet material resistivity is with temperature and the measuring method of pressure change, according to step 3. first in high pressure sealing
The cylindrical permanent magnet sample connected, is then put into high pressure sealing bucket, while will use by the experiment oil of injection 95% in bucket
Carry out the high pressure resistant temperature sensor of monitoring temperature with pressure sensor while being put into high pressure sealing bucket, make temperature sensor, pressure
Force snesor and cylindrical permanent magnet sample are placed on same position height, by high pressure sealing bung it is tight after, using with high densification
The pressure value sealed in the connected compression pump rise high pressure sealing bucket of bucket, the big I of pressure value is read by pressure sensor.
Described permanent-magnet material resistivity with temperature and the measuring method of pressure change, according to step 1. with 2. by heating electric
Cable winds around the outer surface of high pressure sealing bucket, and the end of heating cable is connected into the adjustable alternating current of frequency and amplitude
On source, then superscribe insulating heat insulating material in the outer surface of heating cable, using high pressure sealing bucket in temperature sensor with
When monitoring high pressure sealing bucket in temperature, the output of AC power is then adjusted according to actual measurement.
Described permanent-magnet material resistivity with temperature and the measuring method of pressure change, according to step 1. with 2. directly will be resistance to
The high-power electric heater of pressure is put into high pressure sealing bucket, and the lead of high-power electric heater passes through the close of high pressure sealing barrel top cover
Seal fairlead to draw, and the lead of high-power electric heater is connected in frequency and the adjustable AC power of amplitude, also with
Temperature sensor in high pressure sealing bucket monitors the temperature in high pressure sealing bucket at any time, and AC power is then adjusted as needed
Output, now high pressure bucket is outside still needs to superscribe insulating heat insulating material.
Beneficial effect：
1. the present invention can very easily measure the resistivity of cylindrical permanent magnet sample with temperature and the change feelings of pressure
Condition.
2. the accuracy that the present invention measures the uniformity for obtaining result every time can reach more than 98%.
3. the method that temperature proposed by the present invention and pressure are realized jointly can be applied in the detection of different materials, have
Wide application prospect.
Embodiment：
Embodiment 1
A kind of permanent-magnet material resistivity is with temperature and the measuring method of pressure change, and measurement permanent-magnet material resistivity is with temperature
And the step of pressure change is as follows：
1. the resistance value and record of cylindrical permanent magnet sample under normal temperature and pressure are measured first, then cylindrical permanent magnet is tried
Sample is fixed on the insulating material, is put into high pressure sealing bucket, afterwards, and heating cable is closely wound in the outer surface of high pressure sealing bucket
Or it is directly placed into pressure-resistant high-power electric heater in high pressure sealing bucket.
2. heating cable or high-power electric heater are connected into AC power, adjusts the output voltage of AC power, utilized
Load high pressure sealing temperature within the barrel sensor probe to observe the temperature value in the high pressure sealing bucket that temperature sensor is shown at any time,
The temperature value is kept at least 30 minutes after temperature value needed for reaching, and records temperature value T now, then starts measurement.
3. after the temperature of cylindrical permanent magnet sample is up to standard, the compression pump being connected with high pressure sealing bucket is adjusted, it is slow to increase
Increase the pressure value shown on the pressure value shown on the pressure value in means of press seals bucket, observation pressure sensor, pressure sensor
Accuracy is greater than the value shown by the pressure gauge on compression pump, and closer to the actual value in high pressure sealing bucket.
4. the pressure value P shown by record pressure sensor, and measure the resistance value of obtained cylindrical permanent magnet sample
R, and calculate the permanent magnet sample resistivity of cylindrical permanent magnet sample different pressures at such a temperature：
Formula one
In formula, S is the cross-sectional area of cylindrical permanent magnet sample；For the distance between voltage detecting end.
5. repeat step 1.~step 4., the cylindrical permanent magnet sample under measurement different temperatures corresponding to different pressure
Resistance value R, and calculate corresponding permanent magnet sample electricalresistivityρ.
Embodiment 2
Embodiment 1 chooses four different positions first on cylindrical permanent magnet sample, by the extraction of resistance measuring instrument
Four positions of line and this are in contact, and outermost two positions of cylindrical permanent magnet sample are galvanic contact end, cylindrical magnet
Two positions on the inside of body sample are voltage detecting end, and then directly can obtain cylindrical permanent magnet by resistance measuring instrument tries
The resistance R of sample, the cylindrical permanent magnet sample resistance R obtained according to measurement, calculate the resistance for obtaining cylindrical permanent magnet sample
RateFor：
In formula, S is the cross-sectional area of cylindrical permanent magnet sample；For the distance between voltage detecting end.Measure permanent magnetism
Body material resistance and the method for calculating its resistivity, mainly use Kai Erwen four-end methods.
Embodiment 3
3. permanent-magnet material resistivity described in embodiment 1 first exist with temperature and the measuring method of pressure change according to step
The cylindrical permanent magnet sample connected, is then put into high pressure sealing bucket by the experiment oil of injection 95% in high pressure sealing bucket,
It will be simultaneously put into high pressure sealing bucket for the high pressure resistant temperature sensor of monitoring temperature and pressure sensor simultaneously, pass temperature
Sensor, pressure sensor and cylindrical permanent magnet sample be placed on same position height, by high pressure sealing bung it is tight after, using with
Pressure value in the connected compression pump rise high pressure sealing bucket of high pressure sealing bucket, the big I of pressure value is read by pressure sensor
Go out.
Embodiment 4
Permanent-magnet material resistivity described in embodiment 1 with temperature and the measuring method of pressure change, according to step 1. with 2.
Heating cable is wound around to the outer surface of high pressure sealing bucket, and it is adjustable that the end of heating cable is connected into frequency and amplitude
AC power on, then superscribe insulating heat insulating material in the outer surface of heating cable, utilize high pressure sealing bucket in temperature
Sensor monitors the temperature in high pressure sealing bucket at any time, then adjusts the output of AC power according to actual measurement.
Embodiment 5
Permanent-magnet material resistivity described in embodiment 1 with temperature and the measuring method of pressure change, according to step 1. with 2.
Directly pressure-resistant high-power electric heater is put into high pressure sealing bucket, the lead of high-power electric heater passes through high pressure sealing bucket
The sealing wire hole of top cover is drawn, and the lead of high-power electric heater is connected in frequency and the adjustable AC power of amplitude,
The temperature in high pressure sealing bucket is monitored at any time also with the temperature sensor in high pressure sealing bucket, and then regulation is handed over as needed
The output of power supply is flowed, now high pressure bucket is outside still needs to superscribe insulating heat insulating material.
Embodiment 6
Permanent-magnet material resistivity described in embodiment 1 can also be used and first passed through with temperature and the measuring method of pressure change
Pressure value in compression pump regulation high pressure sealing bucket, the then temperature in regulation high pressure sealing bucket, but real in high pressure sealing bucket
The pressure change that the pressure value on border should be caused by high pressure sealing temperature within the barrel is added caused by compression pump in high pressure sealing bucket
Pressure change；Temperature needed for being reached due to the temperature in high pressure sealing bucket is slowly more compared to the change of pressure, this
Allow for when adjusting the temperature in high pressure sealing bucket, permanent magnet sample is chronically under high-pressure situations, and this is unfavorable for cylinder
The long-term use of permanent magnet sample, in view of the reason for the above, recommending to use measuring process proposed by the present invention.
In view of the particularity of permanent-magnet material application, identical by two to measurement of its resistivity with temperature and pressure change
Process composition, when first process is that permanent magnet sample does not magnetize, measure change of its resistivity with temperature and pressure, second
Individual process is after identical permanent magnet sample saturation magnetizes, to measure change of its resistivity with temperature and pressure.
Also permanent magnet sample can be processed into strip for some permanent magnet samples for being difficult to be processed into cylinder, for
The measuring principle and measuring process of the permanent magnet sample of strip are identical with cylindrical permanent magnet sample.
Certainly, described above is not limitation of the present invention, and the present invention is also not limited to the example above, this technology neck
The variations, modifications, additions or substitutions that the technical staff in domain is made in the essential scope of the present invention, should also belong to the present invention's
Protection domain.
Claims (5)
1. a kind of permanent-magnet material resistivity is with temperature and the measuring method of pressure change, it is characterized in that：Measure permanent-magnet material resistance
The step of rate is with temperature and pressure change is as follows：
1. the resistance value and record of cylindrical permanent magnet sample under normal temperature and pressure are measured first, then cylindrical permanent magnet sample is consolidated
It is fixed to be put on the insulating material in high pressure sealing bucket, afterwards, be closely wound in the outer surface of high pressure sealing bucket heating cable or
Pressure-resistant high-power electric heater is directly placed into high pressure sealing bucket；
2. heating cable or high-power electric heater are connected into AC power, adjusts the output voltage of AC power, utilize loading
High pressure sealing temperature within the barrel sensor probe observes the temperature value in high pressure sealing that temperature sensor is shown bucket at any time, reaches
The temperature value is kept at least 30 minutes after required temperature value, and records temperature value now, then starts measurement；
3. after the temperature of cylindrical permanent magnet sample is up to standard, the compression pump being connected with high pressure sealing bucket is adjusted, height is slowly increased
The pressure value shown on the pressure value shown on pressure value in means of press seals bucket, observation pressure sensor, pressure sensor is accurate
Degree is greater than the value shown by pressure gauge on compression pump, and closer to the actual value in high pressure sealing bucket；
4. the pressure value shown by record pressure sensor, and measure the resistance value R of obtained cylindrical permanent magnet sample, and count
Calculate the permanent magnet sample resistivity of cylindrical permanent magnet sample different pressures at such a temperature：
Formula one
In formula, S is the cross-sectional area of cylindrical permanent magnet sample；For the distance between voltage detecting end；
5. repeat step 1.~step 4., the electricity of the cylindrical permanent magnet sample under measurement different temperatures corresponding to different pressure
Resistance R, and calculate corresponding permanent magnet sample electricalresistivityρ.
2. permanent-magnet material resistivity according to claim 1 is with temperature and the measuring method of pressure change, it is characterized in that：It is first
Four different positions are first chosen on cylindrical permanent magnet sample, four positions of the lead-out wire of resistance measuring instrument and this are connected
Touch, outermost two positions of cylindrical permanent magnet sample are two positions on the inside of galvanic contact end, cylindrical permanent magnet sample
Voltage detecting end is set to, the resistance R of cylindrical permanent magnet sample then can be directly obtained by resistance measuring instrument, according to measurement
Obtained cylindrical permanent magnet sample resistance R, calculates the resistivity for obtaining cylindrical permanent magnet sampleFor：
In formula, S is the cross-sectional area of cylindrical permanent magnet sample；For the distance between voltage detecting end.
3. permanent-magnet material resistivity according to claim 1 is with temperature and the measuring method of pressure change, it is characterized in that：Root
According to step, 3. first the experiment of injection 95% is oily in high pressure sealing bucket, is then put into the cylindrical permanent magnet sample connected
In high pressure sealing bucket, while high pressure sealing will be put into simultaneously for the high pressure resistant temperature sensor of monitoring temperature and pressure sensor
In bucket, temperature sensor, pressure sensor and cylindrical permanent magnet sample is set to be placed on same position height, by high pressure sealing bucket
After covering tightly, the pressure value in high pressure sealing bucket is raised using the compression pump being connected with high pressure sealing bucket, the big I of pressure value is led to
Over-pressed force snesor is read.
4. permanent-magnet material resistivity according to claim 1 is with temperature and the measuring method of pressure change, it is characterized in that：Root
According to step 1. with 2. heating cable to be wound around to the outer surface of high pressure sealing bucket, and the end of heating cable is connected into frequency
In the adjustable AC power of amplitude, insulating heat insulating material then is superscribed in the outer surface of heating cable, high densification is utilized
Temperature sensor in envelope bucket monitors the temperature in high pressure sealing bucket at any time, then adjusts AC power according to actual measurement
Output.
5. permanent-magnet material resistivity according to claim 1 is with temperature and the measuring method of pressure change, it is characterized in that：Root
According to step 1. with 2. directly pressure-resistant high-power electric heater is put into high pressure sealing bucket, the lead of high-power electric heater leads to
The sealing wire hole for crossing high pressure sealing barrel top cover is drawn, and the lead of high-power electric heater is connected into frequency and amplitude is adjustable
In AC power, the temperature in high pressure sealing bucket, Ran Hougen are monitored at any time also with the temperature sensor in high pressure sealing bucket
According to the output of regulation AC power is needed, now high pressure bucket is outside still needs to superscribe insulating heat insulating material.
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| CN102507725A (en) * | 2011-10-28 | 2012-06-20 | 北京航空航天大学 | Measuring device and measuring method of superconductive AC magnetic susceptibility |
| CN103675452A (en) * | 2012-09-07 | 2014-03-26 | 中国石油化工股份有限公司 | Rock resistivity testing system and method capable of simulating reservoir conditions |
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Inventor after: Zou Jibin Inventor after: Xiao Lijun Inventor after: Xu Yongxiang Inventor after: Yu Guodong Inventor after: Zou Jiming Inventor before: Zou Jibin Inventor before: Xiao Lijun Inventor before: Xu Yongxiang Inventor before: Zhao Bo Inventor before: Li Yong Inventor before: Shang Jing Inventor before: Wang Jian Inventor before: Zhao Meng |