A Method and Equipment for Continuously Testing the Permeability Coefficient of Rock and Soil Layers

The water pressure test and steady-flow pumping test are still commonly used for measuring the permeability coefficient of rock and soil strata. Limited by the fact that the average value of the permeability coefficient could be obtained only by this testing method, the accuracy of the experimental results of the permeability coefficient for special rock and soil strata is not good. Therefore, a new on-site testing method and equipment for continuously measuring the permeability coefficient of rock and soil strata is studied in this paper. The method is suitable for water pressure testing in borehole and the steady-flow pumping test. The technical proposal is when the pumping test or water pressure test is carried out, the final water penetration will tend to be a stable value, and then, the high-precision current meter probe will be placed at the bottom of the pumping test hole or water pressure test hole. For the pumping test, the current meter will be lifted uniformly from the bottom of the borehole testing section to the stable water level. Meanwhile, the flow rate of a differential zone of the tested section is continuously detected. For the water pressure test, the current meter will be lifted uniformly from the bottom of the borehole test section to the top of the borehole test section, and the flow rate of the differential section will be continuously detected. Through data analysis and processing, not only the average permeability coefficient of the detected sections can be obtained but also the permeability coefficient of the differential section of the rock and soil stratum can be calculated, respectively. Furthermore, the corresponding relationship between the permeability coefficient and the detected location can be obtained. In view of the abovementioned reasons, the leaking point, the specific position, and the leakage quantity of the detected section could be found out accurately, which will improve the accuracy of the testing results obviously.

Transient simulation of vapor-liquid eruption and overpressure in the drainage terminal of an inclined pipeline during pigging process after water pressure test

Pigging technology is widely used in the oil and gas industry. During the course of pigging, after a water pressure test, the instability of the pig caused by terrain fluctuation can affect the stable operation of the pipeline and even cause burst accidents. This paper describes the four stages of pig movement in an inclined pipeline, with vapor-liquid eruption occuring in the last stage. A hydraulic transient model of the pigging operation after a water pressure test is established based on mass conservation and motion equations, the dynamic equation of the pig, and the vapor-liquid eruption model. The model can simulate the status of fluid flow in the pipeline, track the movement of the pig, and predict the pressure pulses. The simulation results are consistent with the data of two burst accidents, which verifies the correctness of the established model and the reliability of the calculated results. It can therefore provide a reliable and effective theoretical basis for developing a pigging plan on site.

Measurement and Evaluation for Interbedded Pore Water Pressure of Saturated Asphalt Pavement under Vehicle Loading

Dynamic water scouring damage is the main cause of pavement structure damage, and the main reason for dynamic water scouring damage is the rapid change of pore water pressure caused by vehicle load. Numerical simulation is a commonly used pore water pressure test technology, but its accuracy is not high, and the test data are very different to actual values. In this study, a pore water pressure test method is designed, which has the advantages of less disturbance to the pavement structure and the measured data are closer to the true pore water pressure value of the pavement structure. Measurement data show that the pore water pressure gradually increases with increasing vehicle speed, and the pore water pressure response time becomes shorter. The pore water pressure response time is greater than vehicle loading time. Moreover, the phenomenon of periodic decay of pore water pressure with time is analyzed based on hydrodynamic water hammer theory. The empirical formula of maximum positive pressure with speed and the empirical formula of Abp at different speeds were obtained.

ANALISA TEKNIS PENGUJIAN KEKEDAPAN PENGELASAN PADA TANGKI TONGKANG DENGAN MEMBANDINGKAN METODE CHALK TEST, AIR PRESSURE TEST DAN VACUUM TEST

PT. Dock & amp; perkapalan kodja nautical ( persero ) shipyard banjarmasin is a company that move in ship industry, development for shipbuilding industry large enough aims to meet the needs of countries will ships as a country maritime .In doing their activities, company got a job as the construction of ships new, work a serviceman a ship etc. The field of that is associated with welding, welding identical also with a flaw and fraud especially on the part affected a serviceman . Testing impermeability a tank were done in order to the examination of the possibility of mismanagement of a connection is welding and why ensure the quality of welds, an adequate number of qualified to leakage in the connection las can be seen from that there was an indication who occuring when testing done in the same manner .There are several a method of testing, and among the companies were a method of lime oil , water test and a vacuum test drives in .Chalk test drives in / lime oil is a method of welding stability testing traditional tank , water pressure test drives in is a method of welding stability testing a tank by the principle of the compressed air and a vacuum test drives in also made use of of the nature of soapy water , only on the implementation of the activity a method of testing is provided by way of an instrument a vacuum box shaped with one of the sides open and one of the sides made from the materials of glass . In the process of testing kekedapan welding a method of the most accurate in a reading of a point to leakage in connection las that is a method of water pressure test/the compressed air with flattened flattened a reading of a point leakage is more than 1 in any its testing. A method of tests need time in at least the process that is a method of vacuum test and water pressure test.Testing first method vacuum test 1.15 hours and water pressure test by 0.47 hours. Testing second method vacuum test 1.30 hours and water pressure test 1.20 hours. Testing third method vacuum test 0.40 hours and water pressure test 0.50 hours. Testing fourth method vacuum test 1.15 hours and water pressure test 1.20 hours. Testing fifth method vacuum test .30 hours and water pressure test 0.37 hours. Testing sixth method vacuum test 1.40 hours and water pressure test 1.30 hours.

Experiment and Dynamic Simulation of PIG Motion during Pigging Operation in a Slope Pipeline

Pigging techniques are widely used in the oil and gas industry. The unsteady motion of the PIG in an undulating pipe section during the pigging process after a water pressure test affects the stable operation of the pipeline and also causes a pipe rupture accident in serious cases. First, an experimental study was conducted to investigate the pigging process of air–water two phase pipe flows, and the PIG reverse movement and hydraulic pulse phenomenon were observed. Subsequently, a hydraulic transient model of the pigging process after a water pressure test was established in a dual-grid system. The model combined mass and motion equations of gas and liquid and PIG dynamic equations, considered three types of PIG motion states, namely positive movement, reverse movement and still, and used the method of characteristics to solve the equations. The model exhibits the ability for PIG tracing and hydraulic pulse prediction. It can be used to obtain the position and speed of the PIG. Finally, the field data and simulation results were compared, and the results indicated that they are essentially identical. This verified the accuracy of the model that is established in this study and the reliability of computed results and provided a reliable and effective theoretical basis for the development of field pigging plans.