Conical Pick Production Process

Abstract

One of the basic methods of mechanical rock mining is cutting, which faces increasingly difficult working conditions. Despite the rapid development of machines used in underground and opencast mining as well as in tunnel building, construction industry and road engineering, the problem of insufficient durability of mining tools remains unsolved. In addition to drilling and, to a lesser extent, planing, cutting provides a huge market for tools. Currently, the process of cutting is mainly based on conical picks. The cutterheads of cutting machines are equipped with several dozen, and frequently – more than one hundred conical picks, which, due to their workability and abrasiveness, sometimes work only a few hours. There is a market demand for over two hundred models of conical picks. This is due to the huge variety of shapes and sizes of picks as well as the methods of their mounting in the holder. The article briefly presents various solutions of conical picks, their construction, methods of protection, dimensions and materials used. Next, based on materials produced by ZWM Carbonex, the classic method of their manufacture using the turning technology has been described. The authors have also presented briefly the use of die forging for the large-scale production of picks, applied by Górnicza Fabryka Narzędzi Sp. z o.o.

Increasing the Durability of Tools for Forest Road Maintenance

“…The body of the pick and the gripping part are made of steel characterized by high impact strength (usually U > 25 Jcm −2 ) and very high tensile strength (R m > 1000 MPa), as well as resistance to abrasive wear. The working part should have a hardness of at least 45 HRC, while the hardness of the gripping part should be in the range of 25 HRC-35 HRC [15]. Depending on working conditions, various types of steel are applied, such as 14NC11, 41Cr4, 40NiCr6, 36CRNIMo4 or 34CRMo4 (designations according to EN 10084).…”

“…These layers are made by hardfacing with electrodes. The hardness of the coatings may exceed 60 HRC [15].…”

“…Usually, these parameters amount to the following [15]: Many models of picks are available on the market, differing in material and geometrical parameters, shape and assembly method. This results in the existence of more than two hundred models of picks.…”

Tangential rotary picks: Wear modeling and reusability evaluation

“…Polish scientists propose a composite design of a conical pick with a replaceable member represented by a tungsten-carbide nose bit. The nose bit is held in the center of the holder by a spring ring [11,12]. The nose bit may be made of sintered carbide or diamond-coated sintered carbide.…”