Modern coal mines operate high-productive heading machines and cutter-loaders equipped with tangential rotary picks (TRP). Structurally, such a pick represents a cutter block, composed of a backend and a head end as a rotary body, and a hard-allow reinforcement insert brazed-in in the head end point. The pick is operated until the hard-allow material shows wear, after which it is removed and often discarded. Only 20-30% of the tool is spent for rock cutting, the rest goes to waste. Many TRP are lost in the course of cutting because of unreliable attachment. Another drawback of the currently operating cutter picks is their non-interchangeability. Even within the same series, a cutter-loader is equipped with the picks that only fit this very model. As a consequence, it is required to purchase and store great many picks of different dimension, and if the same kind picks become shabby and their supply is exhausted, a cutter-loader will simply stand idle. This explains the low resource-efficiency of the operating cutting tools and calls for designing a new cutter pick. The research aimed at enhancement of cutting machine life at the reduced metal consumption has resulted in the development of a multiple use pick (MUP) with the head end with a replaceable working part. Moreover, the newly designed backend of the cutter pick is equally suitable for operation on various model cutter-loaders. The new engineering solution consists in making a row of holes at the end of the backend, in perpendicular to the backend axis and at a certain distance from the head end. After the cutter pick is fixed in the holder, a collar is put on the backend and a forelock is placed in the respective hole. The lock-up hole is chosen based on the length of the sleeve of the holder, so that to eliminate axial movement of the cutter pick. The industry testing of MUP has been carried out in Pervomaiskaya mine, Berezovsky town, Kemerovo Region. As follows from the test results, the life of PUM per a single operation cycle 5-10 times exceeds the life of Kennametal cutters and RSH picks that are currently in use in the mine. Over the period of the industry testing, MUP have endured 9 operation cycles. Metal consumption for rock cutting has reduced 20 times. The profitability of spending for MUP has made 10.5 or 950%. The industry testing of the developed multiple use picks for cutter-loaders has demonstrated high reliability and longevity of the new design tools, as well as their extended service life and good maintainability.
ASJC Scopus subject areas
- Geotechnical Engineering and Engineering Geology