Abstract: At present，during the use of the comprehensive excavation technology in the construction of a coal mine，the problem of the slow progress of the construction of the roadheader，the difficulty of safety management，and the excessive dependence on the operation experience of the driver of the roadheader without a reliable calculation method are common.Provide reliable numerical calculation method for the steering construction of the roadheader and complete the steering construction of the roadheader safely and efficiently.The research uses simplified trajectory of the roadheader's steering construction，combined with mathematical modeling methods.Through the mathematical operation，the minimum range and length calculation formula for the expansion work during the turning construction of the roadheader was obtained.The calculation formula has important guiding significance for the steering construction of the roadheader.

Key words: Roadheader,Steering Construction,Mathematical Modeling,Erasing Dimension