Mud shale brittle nature experimental device and experimental analysis method thereof

Abstract

The invention relates to a mud shale brittle nature experimental device and an experimental analysis method of the mud shale brittle nature experimental device. The device comprises a pair of guide upright posts, a transverse guide post, a longitudinal guide post and a drop hammer, wherein sliding slots are respectively formed on the side walls of the pair of the guide upright posts along the vertical direction, the two ends of the longitudinal guide post are respectively connected with a driving module and the drop hammer, the transverse guide post and the longitudinal guide post are connected into a whole, and the two ends of the transverse guide post are movably arranged in the sliding slots. The experimental method comprises the following steps: enabling the drop hammer to drop to smash a rock sample to be tested, sequentially screening scrap into a plurality of groups by using different specifications of screens, figuring out the weight percentage of the group with the smallest specification by a weight method, figuring out the total newly increased surface area of the sample after smashing by using a surface area method and further analyzing the brittle nature of the rock sample to be tested; and compared with the prior art, the device provided by the invention has the advantages of loose requirements on appearance of the rock sample to be tested, simplicity and convenience in operation, high precision and small influence caused by human factors, and a new concept is provided for evaluation and research of mud shale.

Description

technical field [0001] The invention relates to the field of measurement of rock mechanical parameters, in particular to an experimental device and an experimental method for shale brittleness properties. Background technique [0002] The brittle cracking of mud shale is a common phenomenon in drilling and laboratory testing. The brittle cracking property refers to the property that the material only produces small deformation, that is, fracture damage, under the action of external force, such as stretching and impact. [0003] In the process of drilling and coring, shale cores often break when they come out of the barrel, and cracks often occur when drilling test core columns in the laboratory. These are the specific manifestations of shale brittleness. [0004] In recent years, more and more attention has been paid to the brittle nature of shale in the field of oil and gas geology, and more and more research results have been obtained. Axial and triaxial experiments are u...

AI Technical Summary

Problems solved by technology

[0021] 1) The heavy hammer is manually controlled through the rope. Due to the different operating habits and methods of the operator, it may have a certain impact on the crushing of the sample and further affect the accuracy of the data;

[0022] 2) During the falling process of the weight, there may be friction with the inner wall of the cylinder, so that the weight falls in a non-free fall, resulting in deviations in the obtained data;

[0023] 3) After the sample is broken, it is at the bottom of the cylinder. It is necessary to manually lift the cylinder and pour the broken sample into a special sample collection part. The cylinder is nearly 70cm long, and a little careless operation will cause some parts to be broken. Powdery samples remain in the cylinder, which affects the accuracy of the data;

[0024] 4) Compact the collected samples with a particle size of less than 0.5mm in a graduated cylinder and measure the height. Since the measurement is done manually, there may be human errors in the data obtained by different operators, which will ultimately affect the accuracy of the analysis

[0026] 1) The drop weight method is an experimental method applied to the detection of the physical properties of coal samples, and no researchers have applied it to the detection experiment of the brittle fracture properties of shale;

[0027] 2) After the sample is crushed by the falling weight method, only samples with a diameter of less than 0.5mm are collected and analyzed based on the height of the sample in the measuring cylinder, which will inevitably result in the loss and incompleteness of the information on the fracture properties of the sample

[0028] The various experimental research methods and results mentioned above can reflect the brittleness of rocks to a certain extent. There is no unified statement with the measurement

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