Abstract: The construction of high level chute has always been a technical problem. In order to construct high level chute easily，safely and efficiently，Makeng Iron Mine plans to adopt Vertical Crater Retreat well forming blasting technology to solve the construction problems of high level chute，such as poor construction environment and difficult ventilation. Based on the Livingston blasting funnel theory，the single-hole blasting funnel experiment was carried out in Makeng Iron Mine. No. 2 rock emulsion explosive was used in the experiment，and its dosage was 150 g and 300 g respectively.According to the experimental results，the optimal buried depth of the charge and the radius of the blasting funnel are obtained.Then，according to the proportional embedding depth of the charge package and the corresponding radius of the blasting funnel，the reasonable spacing of the holes，the charging length and the blocking length of the hole bottom of the VCR well forming technology were determined by the formula conversion of the blasting funnel volume per unit explosive amount.

Key words: single-hole blasting funnel test, VCR drilling, high level chute, optimal burial depth of ex? plosive package