US 11,959,379 B2
Method for measuring gas pressure of close-distance seam group simultaneously
Shaobo Li, Huainan (CN); Lei Wang, Huainan (CN); Xingang Niu, Huainan (CN); Chuanqi Zhu, Huainan (CN); Zhenyu Yang, Huainan (CN); Lipeng Chen, Huainan (CN); and Yu Zhang, Huainan (CN)
Assigned to Anhui University of Science and Technology, Huainan (CN)
Filed by Anhui University of Science and Technology, Huainan (CN)
Filed on Nov. 9, 2023, as Appl. No. 18/505,882.
Application 18/505,882 is a continuation of application No. PCT/CN2022/086998, filed on Apr. 15, 2022.
Claims priority of application No. 202210303035.7 (CN), filed on Mar. 24, 2022.
Prior Publication US 2024/0068359 A1, Feb. 29, 2024
Int. Cl. E21B 47/06 (2012.01); C04B 28/00 (2006.01); E21F 17/18 (2006.01)
CPC E21B 47/06 (2013.01) [C04B 28/00 (2013.01); E21F 17/18 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A method for measuring gas pressure of a close-distance seam group simultaneously, comprising the following steps of:
(1) constructing a drill hole in a direction near to a lower seam in a roadway; the drill hole being obliquely set, and a bottom of the drill hole entering a base plate of the seam for a certain distance; and adopting a water suction pump after the drill hole construction being completed, and pumping out accumulated water in the drill hole by connecting the pump with a flexible pipeline;
(2) lowering a first seam piezometer tube in the constructed drill hole; sequentially lowering a baffle and a polyurethane blocking material along the first seam piezometer tube after a tube head of the first seam piezometer tube reaching a position of a lowermost seam; and installing a corresponding gas pressure gauge on the first seam piezometer tube after the polyurethane blocking material solidifying;
(3) lowering a second seam piezometer tube; after a tube head of the second seam piezometer tube reaching a position of a second layer of seam in relative to the lowermost seam, sequentially lowering the baffle and the polyurethane blocking material at this seam position along the second seam piezometer tube; and installing a corresponding gas pressure gauge on the second seam piezometer tube after the polyurethane blocking material solidifying;
(4) lowering a nth seam piezometer tube; sequentially lowering the baffle and the polyurethane blocking material along the nth seam piezometer tube after a tube head of the nth seam piezometer tube reaching a position of a nth layer of seam in relative to the lowermost seam; and installing a corresponding gas pressure gauge on the nth seam piezometer tube after the polyurethane blocking material solidifying;
(5) injecting a high-water and quick-solidifying material into the drill hole through a grouting pipe; and after injecting the high-water and quick-solidifying material into an orifice, stopping grouping and removing the grouting pipe; and
(6) connecting various gas pressure gauges through optical fibers, and connecting the gas pressure gauges with a ground control system;
wherein in step (5), the high-water and quick-solidifying material is composed of a material A and a material B which are mixed in a weight ratio of 1:1, after mixing, 90%-95% of water is added for use, wherein the material A comprises the following raw materials in parts by weight: 50-70 parts of monohydrallite and 5-10 parts of compound super-retarding dispersing agent, and the material B comprises the following raw materials in parts by weight: 10-30 parts of lime, 10-30 parts of gypsum, 5-10 parts of Baifang thiophanate methyl suspending agent and 5-10 parts of compound fast-setting early strength agent; the compound super-retarding dispersing agent comprises sodium hexametaphosphate, phosphine butanetricarboxylic acid and water, and a weight ratio of the sodium hexametaphosphate to the phosphine butanetricarboxylic acid to the water is (10-15):1:3; and the compound fast-setting early strength agent comprises lithium carbonate, calcium formate, desulfurized gypsum and sodium nitrite, and a weight ratio of the lithium carbonate to the calcium formate to the desulfurized gypsum to the sodium nitrite is 1:3:(15-20):(15-20).