초록 ▼

The invention provides a pressure measuring method and device that are capable of easily measuring the volume of a pipe that is an object of inspection and of eliminating the influences of a change in temperature in the pipe. A pressure measuring method using a pressure sensor 4 connected to a pipe

The invention provides a pressure measuring method and device that are capable of easily measuring the volume of a pipe that is an object of inspection and of eliminating the influences of a change in temperature in the pipe. A pressure measuring method using a pressure sensor 4 connected to a pipe for feeding a gas thorough a connecting portion for measuring the pressure in the pipe, the method being characterized in that the method comprises a pressurizing step for pressurizing the inside of the pipe by a pump 5 with the pipe held in the closed state, and a step for measuring an amount of pressure change of the pipe in the standing state after completion of the pressurization step, and in that an amount of pressurization change of the in-pipe pressure by the pressurization step, and the flow rate of the gas fed into the pipe during pressurization are measured, and the volume of the pipe in the closed state is calculated on the basis of the amount of pressurization change and the flow rate of the gas, and the amount of leakage of the gas from the pipe is calculated on the basis of the volume of the pipe and the amount of pressure change in the standing state.

대표청구항 ▼

What is claimed is: 1. A pressure measuring method which, by connection to a pipe for feeding a gas or a liquid, measures pressure in said pipe, comprising a pressurizing and depressurizing step for pressurizing or depressurizing the inside of the pipe held in a closed state, and a measuring step

What is claimed is: 1. A pressure measuring method which, by connection to a pipe for feeding a gas or a liquid, measures pressure in said pipe, comprising a pressurizing and depressurizing step for pressurizing or depressurizing the inside of the pipe held in a closed state, and a measuring step for measuring an amount of pressure change of the pipe in a standing state after completion of said pressurizing and depressurizing step, wherein, before said pressurizing and depressurizing step, said pipe is closed after adjusting in-pipe pressure to match pressure outside the pipe, and an amount of pressure change in the pipe due to temperature change is measured, and a value of said amount of pressure change in the standing state is amended in accordance with said amount of pressure change due to the temperature change, and influences of the temperature change on the pressure change in the standing state are eliminated. 2. The pressure measuring method as claimed in claim 1, wherein, in measuring said amount of pressure change in the standing state, said amount of pressure change is re-amended on the basis of an amount of change of actually-measured temperature of the gas or the liquid in the pipe, or actually-measured temperature of the pipe. 3. The pressure measuring method as claimed in claim 1, wherein, when measuring pressure several times, said pressurizing and depressurizing step is conducted by performing pressure measurement in pressurization condition and pressure measurement in depressurization condition in combination. 4. The pressure measuring method as claimed in claim 1, wherein said amount of pressure change is calculated by approximating several measurement values by straight line. 5. A pressure measuring method which, by the connection to a pipe for feeding a gas or a liquid, measures the pressure in the said pipe, comprising a pressurizing and depressurizing step for pressurizing or depressurizing the inside of the pipe held in the closed state, and a step for measuring an amount of pressure change of the pipe in the standing state after completion of the said pressurizing and depressurizing step, wherein; before the said pressurizing and depressurizing step or after completion of the measurement of the amount of pressure change in the standing state, the said pipe is closed after adjusting the in-pipe pressure to the pressure outside the pipe, and the amount of pressure change in the pipe due to a temperature change is measured, an amount of pressurization and depressurization change of the in-pipe pressure by the said pressurizing and depressurizing step or an additional pressurizing and depressurizing step, and the flow rate of the gas or the liquid which is fed into, or discharged from the pipe during the pressurization or the depressurization, are measured, the volume of the pipe in the closed state is calculated on the basis of the said amount of pressurization and depressurization change, and the said flow rate of the gas or the liquid, the value of the said amount of pressure change in the standing state is amended in accordance with the said amount of pressure change due to the temperature change, and the amount of leakage of the gas or the liquid from the pipe is calculated on the basis of the said amended amount of the pressure change in the standing state and the said volume of the pipe. 6. The pressure measuring method as claimed in claim 5, wherein; at least one of the actually-measured temperature of the gas or the liquid that is fed into a pipe, and the actually-measured temperature of the gas or the liquid that is discharged from the said pipe, is used in calculating the said volume of the pipe. 7. The pressure measuring method as claimed in claim 5, wherein an amount of time for measuring said amount of pressure change of the pipe in the standing state is decided in accordance with the value of said volume of the pipe. 8. The pressure measuring method as claimed in claim 5, wherein, in measuring said amount of pressure change in the standing state, said amount of pressure change is re-amended on the basis of an amount of change of actually-measured temperature of the gas or the liquid in the pipe, or actually-measured temperature of the pipe. 9. The pressure measuring method as claimed in claim 5, wherein, when measuring pressure several times, said pressurizing and depressurizing step is conducted by performing pressure measurement in pressurization condition and pressure measurement in depressurization condition in combination. 10. The pressure measuring method as claimed in claim 5, wherein said amount of pressure change is calculated by approximating several measurement values by straight line. 11. A pressure measuring method which, by the connection to a pipe for feeding a gas or a liquid, measures pressure in said pipe, comprising a pressurizing and depressurizing step for pressurizing or depressurizing the inside of the pipe held in a closed state, and a measuring step for actually measuring an amount of pressure change of the pipe in a standing state after completion of said pressurizing and depressurizing step, wherein, before said pressurizing and depressurizing step, said pipe is closed after adjusting in-pipe pressure to match pressure outside the pipe, and an amount of pressure change in the pipe due to temperature change is measured, a predicted value of said amount of pressure change in the standing state is calculated in accordance with said amount of pressure change due to temperature change, and leakage condition of said pipe is judged by comparing said predicted value with the actually-measured amount of pressure change in the standing state. 12. The pressure measuring method as claimed in claim 11, wherein, in measuring said amount of pressure change in the standing state, said amount of pressure change is re-amended on the basis of an amount of change of actually-measured temperature of the gas or the liquid in the pipe, or actually-measured temperature of the pipe. 13. The pressure measuring method as claimed in claim 11, wherein, when measuring pressure several times, said pressurizing and depressurizing step is conducted by performing pressure measurement in pressurization condition and pressure measurement in depressurization condition in combination. 14. The pressure measuring method as claimed in claim 11, wherein said amount of pressure change is calculated by approximating several measurement values by straight line. 15. A pressure measuring device performing a pressure measuring method which, by connection to a pipe for feeding a gas or a liquid, measures pressure in said pipe, comprising means for pressurizing or depressurizing the inside of the pipe held in a closed state, and means for measuring an amount of pressure change of the pipe in a standing state after completion of said pressurizing and depressurizing step, wherein, before said pressurizing and depressurizing step, said pipe is closed after adjusting in-pipe pressure to match pressure outside the pipe, and an amount of pressure change in the pipe due to temperature change is measured, and a value of said amount of pressure change in the standing state is amended in accordance with said amount of pressure change due to the temperature change, and influences of the temperature change on the pressure change in the standing state are eliminated. 16. The pressure measuring device as claimed in claim 15, further comprising a pressurizing means for pressurizing the inside of the pipe in the inside of said pressure measuring device. 17. The pressure measuring device as claimed in claim 16, further comprising a display part placed in said pressure measuring device, which displays at least one of numerical values measured or calculated by said pressure measuring device, information of operator guidance or operating condition of said pressure measuring device, and past result of measurement or calculation. 18. The pressure measuring device as claimed in claim 16, further comprising a memorizing means which accumulates numerical values measured or calculated. 19. The pressure measuring device as claimed in claim 15, further comprising a display part in said pressure measuring device, which displays at least one of numerical values measured or calculated by said pressure measuring device, information of operator guidance or operating condition of said pressure measuring device, and past result of measurement or calculation. 20. The pressure measuring device as claimed in claim 19, further comprising a memorizing means which accumulates numerical values measured or calculated. 21. The pressure measuring device as claimed in claim 15, further comprising a memorizing means which accumulates numerical values measured or calculated. 22. A pressure measuring method which, by connection to a pipe for feeding a gas or a liquid, measures pressure in said pipe, comprising a pressurizing and depressurizing step for pressurizing or depressurizing the inside of the pipe held in a closed state, and a measuring step for measuring an amount of pressure change of the pipe in a standing state after completion of said pressurizing and depressurizing step, wherein, after completion of the measurement of the amount of pressure change in the standing state, said pipe is closed after adjusting in-pipe pressure to match pressure outside the pipe, and an amount of pressure change in the pipe due to temperature change is measured, and a value of said amount of pressure change in the standing state is amended in accordance with said amount of pressure change due to the temperature change, and influences of the temperature change on the pressure change in the standing state are eliminated. 23. The pressure measuring method as claimed in claim 22, wherein, in measuring said amount of pressure change in the standing state, said amount of pressure change is re-amended on the basis of an amount of change of actually-measured temperature of the gas or the liquid in the pipe, or actually-measured temperature of the pipe. 24. The pressure measuring method as claimed in claim 22, wherein, when measuring pressure several times, said pressurizing and depressurizing step is conducted by performing pressure measurement in pressurization condition and pressure measurement in depressurization condition in combination. 25. The pressure measuring method as claimed in claim 22, wherein said amount of pressure change is calculated by approximating several measurement values by straight line. 26. A pressure measuring device performing a pressure measuring method which, by connection to a pipe for feeding a gas or a liquid, measures pressure in said pipe, comprising means for pressurizing or depressurizing the inside of the pipe held in a closed state, and means for measuring an amount of pressure change of the pipe in a standing state after completion of said pressurizing and depressurizing step, wherein, after completion of measurement of the amount of pressure change in the standing state, said pipe is closed after adjusting in-pipe pressure to match pressure outside the pipe, and an amount of pressure change in the pipe due to temperature change is measured. 27. The pressure measuring device as claimed in claim 26, further comprising a pressurizing means for pressurizing the inside of the pipe in the inside of said pressure measuring device. 28. The pressure measuring device as claimed in claim 26, further comprising a display part placed in said pressure measuring device, which displays at least one of numerical values measured or calculated by said pressure measuring device, information of operator guidance or operating condition of said pressure measuring device, and past result of measurement or calculation. 29. The pressure measuring device as claimed in claim 26, further comprising a memorizing means which accumulates numerical values measured or calculated.