聚氨酯封孔材料在炮孔封堵中的应用探索

Study on Application of Polyurethane Foaming Material in Blast-hole Stemming

为探索聚氨酯封孔材料在炮孔封堵中的应用可行性,通过理论分析炮孔中封堵物的受力情况,对聚氨酯封孔材料的力学性能与安全性能进行了试验研究。实验测试了聚氨酯封孔材料的抗压强度、相对形变以及弹性模量,并采用拉拔法与推出法测试了聚氨酯材料的粘结力。结果显示:聚氨酯封孔材料的平均抗压强度为776.2 k Pa,压缩变形为10%,弹性模量均值为16.66 MPa;拉拔法测得的聚氨酯封孔材料的粘结力为1788 N,粘土的粘结力为835 N;推出法测得的聚氨酯封孔材料的最大推出力为952 N,粘结强度为103.8 k Pa,粘土的最大推出力为692 N,粘结强度为75.5 k Pa。显然,聚氨酯封孔材料的粘结力显著优于粘土,力学性能较好。鉴于聚氨酯材料的发热性,测定了聚氨酯发泡过程的放热性及其对塑料导爆管传爆可靠性的影响。结果显示:聚氨酯封孔材料在反应过程中温度较高,且受用量、环境温度等的影响,存在一定的危险性。

In order to study the feasibility of application of polyurethane foaming material in blast-hole sealing, its mechanical properties and safety performance were tested by experiment based on theoretical analysis of the force of the plug in blast-hole. The compressive strength, relative deformation and elastic modulus of polyurethane foaming materials were determined, and its bond strength was also tested by drawing method and pressing method. The results show that the average compressive strength of polyurethane sealing material is 776.2 kPa, the compression deforma- tion is 10%, the average elastic modulus is 16.66 MPa, the bond force of polyurethane sealing material using drawing method is 1788 N and that of clay is 835 N, and the maximum bond force of polyurethane sealing material and clay u- sing pressing method are 952 N and 692 N, the bond strength are 103.8 kPa and 75.5 kPa. Obviously, the bond strength of polyurethane sealing material is significantly better than that of clay and its mechanical properties are ex- cellent. In view of the exottlermicity of polyurethane sealing material ,the heat released in the process of polyurethane foaming and its influence on the detonation transfer reliability of the plastic tube were also tested. The results show that the temperature in the reaction process is high and influenced by the amount and environment temperature, which should be paid great attention.