Original scientific paper Aiming at answering the questions of wear and failure of hob in the rock breaking process, the rock breaking process was simulated in different broken rock conditions by using finite element method. The relationship between normal force, lateral force, rolling force and time was obtained by rock breaking simulation analysis on the single edge disc cutter. The rock stre...

Computerized grading of hardwood lumber according to NHLA rules would permit fast assessment of sawn lumber and the evaluation of potential edging and trimming operations to improve lumber value. More importantly, to enable optimization of the hardwood lumber sawing process, a fast means of evaluating the potential value of boards before they are sawn is necessary. As log and lumber scanning sy...

* Corresponding author – [email protected] Tel: 414-229-4126 Fax:414-229-6958 ABSTRACT Understanding the fundamental tribology associated with the cutting of rock under extremely high pressure and high temperature (HPHT) conditions are extremely important in mining and drilling operations. In this paper, a rock fragmentation process is simulated during mechanical cutting of rock using an explicit...

Billions of LEDs are used today in traffic control, automotive headlights, flat panel display technology, mobile devices, back lighting, projection and general illumination applications. With the dramatic growth in LEDs, manufacturers are looking for technologies to increase production yield and decrease cost. Sapphire wafer singulation into miniature dies is one of the critical steps used in b...

In Central Europe the main species that are used for the production of sawn wood are spruce, pine, and European beech. After the sawing process, the sawn timber is technically dried to a certain moisture content by means of condensation drying. The water movement in the cellular structure, which is caused by the drying process, draws some of the extractives into solution. In the process of kiln...

Rock abrasivity is an essential factor for selecting cutting tools, estimating tool wear and life, and ultimately, matching various mechanized excavation systems with a given geologic condition. It also assists engineers to determine economic limits of different cutting tools and machines used in civil and mining projects. The Cerchar abrasion test is a simple and most widely used method for ro...

The rising cost of hardwood sawlogs has increased sawmill managers’ interest in considering the installation of thin-kerf sawing machines in their sawmills. Replacement of circular headrigs by band headrigs and/or reducing resaw kerfs are the available options. Equipment replacement or modification to achieve thin-kerf sawing will require an investment. Sawmill managers making such an investmen...

The paper presents the results of a simulation study, where log models based on CT scanned logs of Scots pine (Pinus sylvestris L.) was used as input material to a computer simulation model of a generic value chain involving sawing, drying, crosscutting and finger jointing. The aim was to investigate which factors that affect the volume yield in the value chain, be it forestal, log-, processor ...