取芯管取芯过程管壁温度变化特性试验*

为给冷冻取芯过程中瓦斯解吸模拟试验提供依据，依托自主研制的取芯管管壁温度自动采集装置，研究不同取芯深度及煤体破坏类型下取芯过程管壁温度变化特性。结果表明:在原生结构煤中取芯时，取芯过程管壁温度变化主要分为3个阶段，即稳定不变阶段、快速上升阶段与缓慢下降阶段，分别对应进钻、取芯与退钻过程；在构造煤中取芯时，管壁温度变化可分为缓慢上升阶段、快速上升阶段与缓慢下降阶段，分别对应进钻、取芯与退钻过程。在构造煤中，取芯深度越大，取芯管管壁升温幅度越大，取样过程中管壁温度峰值越大，且在取芯过程中，取芯管管壁温度传感器B1，B2，B3存在温升滞后现象；同一取芯深度，煤体破碎程度越大，取芯管管壁升温幅度越小，取芯结束时取芯管管壁温度越低。

Experimental study on temperature variation characteristics of tube wall during coring process of coring tube

In order to provide the basis for the simulation experiments of gas desorption in the process of freezing coring,based on the self developed automatic measuring device for the tube wall temperature of coring tube,the change characteristics of tube wall temperature during the coring process under different coring depths and types of coal body destruction were studied.The results showed that when coring in the primary structure coal,the change of tube wall temperature during the coring process mainly underwent three stages,namely the stable stage,the fast rising stage and the slow falling stage,corresponding to the drilling in process,coring process and drilling out process,respectively.When coring in the structural coal,the change of tube wall temperature underwent the slow rising stage,the fast rising stage and the slow falling stage,corresponding to the drilling in process,coring process and drilling out process,respectively.In the structural coal,the greater the coring depth,the larger the temperature rise amplitude of the tube wall temperature of coring tube,and the larger the peak temperature of tube wall during the coring process.In the process of coring,the sensors B1,B2 and B3 for the tube wall temperature of coring tube presented the phenomenon of temperature rise lag.Under the same coring depth,the greater the crushing degree of coal body,the smaller the temperature rise amplitude of the tube wall temperature of coring tube,and the lower the tube wall temperature of coring tube at the end of coring.