The invention relates to a process for producing a superfine high-purity 
quartz glass 
pipe for a high-temperature sensor, which is characterized by comprising the following steps of: finely selecting 
quartz blocks as raw materials, wherein the particle size of the 
quartz blocks is 20-30 mm, and the content of SiO2 is above 99%; sequentially carrying out soaking in 
hydrochloric acid, 
roasting, water 
quenching, mechanical pulverization, 
iron removal, soaking in mixed acid, high-temperature stirring and washing and high-temperature chloridization on the raw materials to obtain high-purity quartz sand; then throwing the high-purity quartz sand in a quartz furnace for 
smelting, pulling into a quartz glass 
pipe, and then scouring, 
cutting, trimming, ultrasonic cleaning and dehydroxylating so that a finished product is obtained. The quartz glass 
pipe produced and prepared by the process has the superfine and ultrathin features, has the characteristics of high-
temperature resistance, 
molten steel and glass liquid-washing resistance, corrosive resistance, 
high heat transfer speed, good soaking performance, large strength, long service life, no 
bursting under shock heating and cooling condition, strong process 
operability, scale production and the like, and completely accords with the requirements of various performance indexes of the quartz glass pipe used as an outer protective pipe of the high-temperature sensor.