optimization for trenchless reconstruction of pipelines

Today the technologies of trenchless reconstruction of pipelines are becoming and more widely used in Russia and abroad. One of the most perspective is methods is shock-free destruction of the old pipeline being replaced with the help of hydraulic installations with working mechanism representing a cutting unit with knife disks and a conic expander. A construction of a working mechanism, which allows making trenchless reconstruction of pipelines of different diameters, is optimized and patented and its developmental prototype is manufactured. The dependence of pipeline cutting force from knifes obtusion of the working mechanisms. The cutting force of old steel pipelines with obtuse knife increases proportional to the value of its obtusion. Two stands for endurance tests of the knifes in laboratory environment are offered and patented