张集矿副井冻结管局部保温效果研究

Study on Partial Insulation Effect of Frozen Pipe in Auxiliary Shaft of Zhangji Mine

摘要: 针对当前深井冻结时间长、冷量散失大、产生冻胀力大等与永久井架基础安全稳定性的矛盾，分析冻结管抽真空保温与聚氨酯保温的优劣性。现场实验表明，抽真空冻结管隔温效果差、持续时间短，聚氨酯保温时间长效果好，在−32℃盐水冻结170天后，冻结管保温层外侧温度为−6℃，未保温冻结管外侧温度为−23℃，温差达17℃；测点离冻结管越近，地层降温梯度越大； 随着冻结时间的增长，保温与未保温冻结管外温度差先增大后减小。最后通过有限元模拟验证保温后温度发展情况，并提出聚氨酯保温的节能发展前景。

Abstract: For the contradiction between the derrick base stability and other factors such as long freezing time, large cooling capacity loss, large frost heaving force and so on, the superiority-inferiority of the vacuum insulation and the polyurethane insulation is analyzed. Field experiment shows that the vacuum insulation effect is poor and short duration, while the other one is good with long duration. After 170 days of freezing in −32˚C, the outside temperature of the insulation pipe is −6˚C, while the outside temperature is −23˚C without insulation. The temperature difference is 17˚C. The closer the measuring point is to the freezing pipe, the higher the temperature gradient is. With the increase of freezing time, the temperature difference between the thermal insulation and the non-thermal insulation freezing tube first increases and then decreases. Finally, the development of temperature after thermal insulation is verified by finite element simulation, and the development prospect of energy saving of polyurethane insulation is put forward.