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This article presents the results of works aiming at observations of wearing high speed steel (HSS) milling blades, coated with application of ZeroFlow gas nitriding method, after peripheral machining of dry beech wood. The thin nitrided layer on a HSS blades of HS18-0-1, T grade, and HS6-5-2, T-M grade influences the nature and value of changes in VBf, VBw, VBs, and ρmi, cutting edge wearing parameters, as the cutting distance increases. From the point of view of minimum cutting edge round up, the HS18-0-1 steel grade seems to be superior under the HS6-5-2 steel grade. From the perspective of the cutting edge recessions measured on the: (*) clearance surface VBf, and (**) rake surface VBs, the HS6-5-2 steel grade seems to be slightly better. The cutting edge recession measured on the bisector of the wedge angle VBw appeared to have similar values for both examined steel grades, independent of the values of other controlled parameters: Ls - the cutting path; ßf - the cutting edge wedge angle; BaN - the Barkhausen noise indicator. An increase in the Barkhausen noise indicator slightly decreases the cutting edge recessions expressed by VBf, VBw and VBs parameters. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to provide a contribution on the diffusion of Industry 4 (I4.0)-related knowledge in industrial districts (IDs). The main goal is to examine the dissemination of I4.0 knowledge, exploring the main mechanisms for its spreading and highlighting the main factors shaping such processes. Focus is on dissemination processes in IDs active in traditional industries, which could represent the "periphery" of I4.0 application context. Design/methodology/approach: The methodology is qualitative. Notably, this paper presents a case study of the Pesaro ID specialized in furniture/woodworking machinery sector. A total of 18 in-depth one-to-one interviews have been conducted with relevant informants from a variety of organizations within the cluster: companies, institutions and universities. Findings: The complexity of I4.0 requires a combination of traditional mechanisms with innovative ones within IDs characterized by the emergence of new players, activities and resources. These changes led to three main evolving patterns: the horizon of I4.0 upgrading shows blurred boundaries in terms of sectors and geographic location, the I4.0 diffusion appears fragmented in terms of initiatives and projects by both firms and institutions and the dissemination of I4.0 knowledge pushes ID firms and institutions to pursue deliberate initiatives leading to innovative forms of "collective" cooperation. Originality/value: This paper contributes to both theory and practice. From the theoretical point of view, this paper contributes to the literature on innovation in IDs and clusters on two interrelated grounds. First, it provides further research on I4.0 and IDs and clusters. Second, it contributes to the stream of research on knowledge creation and diffusion in IDs and clusters, providing empirically based insights over emerging local learning processes in IDs. Moreover, relevant managerial and policy implications stem from the analysis. [ABSTRACT FROM AUTHOR]

In forest operations, productivity studies represent one of the central topics because their output is frequently used to develop predictive models, to compare alternatives or just to set production rates and to make informed decisions needed to reach a balance between the work effort and payment. Ecuador has started to change its technology in forest operations by a transition towards the increment of mechanization to procure wood from forests planted for timber production purposes. Nevertheless, the change has brought no new research approaches to check the performance of the new machines. A particular case is that of tree processing operations at the landing by means of double-grip processor machines. This study aimed to evaluate the performance of these machines in processing timber from thinning operations and to estimate, by a check study, the sample size needed for a full-scale study. For this reason, a number of 57 processed trees were included in the study and a detailed time-and-motion analysis was implemented to check the variability and central tendency of the data, a fact that also enabled the operational description. Based on the study outcomes, basic statistics were computed to characterize the performance of the operations under the assumptions of a preliminary study, and the number of observations for a full-scale study were estimated. On average, close to 4 logs were recovered from a tree which resulted in an average work cycle time of 45 seconds that was characterized by a succession of very fast events such as gripping, feeding, and cutting. Elemental cuts, for instance, accounted for a number of 228 observed events and they averaged close to 1.5 seconds. The estimation of the sample size based on a confidence threshold of 95% and on an assumed precision of 5% revealed a rather low number of observations (127) needed at the work cycle level. However, factors such as the variability in some work elements, as well as the occurrence of other work tasks on a regular basis should be considered in the attempt to adopt the sample size and to conduct a full-scale study. Until conducting a full-scale study, the results given herein could serve as reference in the performance of tractor-mounted double-grip processors in landing operations. [ABSTRACT FROM AUTHOR]

In this paper, the energy losses in big band saw machines are investigated. These losses are caused by the geometric and angular inaccuracies with which the leading wheels are made. Expressions for calculating the kinetic energy of the mechanical system in the ideal and the real cases are obtained. For this purpose, expressions for calculating the velocities of the centers of the masses in two mutually perpendicular planes are obtained. A dependence for calculation of the kinetic energy losses of the mechanical system in final form is received. Optimization procedure is used to determine the values of the parameters at which these losses have minimum values. The proposed study can be used to minimize energy losses in other classes ofwoodworking machines. [ABSTRACT FROM AUTHOR]

The article offers information on many safety mechanisms about the use of band saws. According to the U.S. Occupational Safety and Health Administration (OSHA), band saw injuries represent 11.5 percent of saw injuries during the period from 1984 to 2017. Potential hazards associated with band saws include unintentional contact with unguarded moving blades. Also presented are safeguards to avoid band saw incidents such as flesh-sensing mechanisms and blade-housing interlocks.

The article deals with data in the cutting process of wood-based materials. The cutting process influences the shape and dimensions of a cutting edge. The experiments were focused on monitoring the changes of the cutting edge in machining of particle board and the influence of cutting speed on the tool wear. Cutting tests were performed during milling at cutting rates in the range 7.95 to 17.9 m/s (477 to 1074 m/min), a depth of cut of 9.5 mm, and a tooth feed of 0.05 mm. The wear process of cutting wedge during particle board milling is characterized by a decrease in the cutting edge of insert blades. The comparative digital dial gauge was used for measurement of the cutting wedge recession. The course of the wear of wood based materials exhibited similarity in graphical representation with abrasive material cutting. The resulting dependency may be used for selection of the most suitable cutting conditions according to operator requirements. [ABSTRACT FROM AUTHOR]

In Malaysia, the depletion of raw materials has begun to impact mills, as their production could decrease or cease. This will impact the Malaysian wood-based economy, both locally and globally. Usage of trees with fastgrowing characteristics is essential to add feedstock sources to mills. This study investigated the mechanical properties (MOR, MOR, IB, and screw withdrawal) of particleboard (density = 660 kg/m3) made of Leucaena leucocephala, rubberwood, and mixed tropical trees with different species ratios. The wood species ratios for the particleboards were 100% Leucaena, 50% Leucaena and 50% rubberwood, and 50% rubberwood and 50% mixed tropical wood. Boards with the dimensions 3680 mm × 2465 mm × 25 mm were produced. The results showed that all of the species ratios passed the minimum requirements for commercial use. The performance of the Leucaena particleboard was 17.40 MPa (MOR), 2654 MPa (MOE), 0.68 MPa (IB) and 623 N (Screw withdrawal). The Leucaena board performance matched that of the board made from the current raw materials used commercially (mixed tropical wood and rubberwood). [ABSTRACT FROM AUTHOR]

Mobile shields at woodworking machine workstations were considered in this work as part of a protection and accident prevention system. A shield design based on an aluminium frame is proposed. The results of the experimental tests demonstrated the high efficiency of material kick attenuation using the mobile shields, irrespective of their position and the filling used. Operational tests on the mobile shields were performed in a woodworking shop, which confirmed their usefulness and made it possible to supplement the conclusions with interesting observations concerning their dimensional and visual features, among other things. [ABSTRACT FROM AUTHOR]

The aim of the paper is a structural design of a cutting device with option of length adjustment of cutting material. The introductory part of the paper is devoted to an analysis of available devices standardly employed in the process of wooden substance cutting. The core of the paper contains structural design and calculation of the individual parts, disposition solution of the device and a complete visualisation in the 3D models[Krenicky 2010]. The final part of the paper points out a necessity of application of newly-designed devices intended for wooden substance cutting as such case offers an absolute waste less utilization of wooden substance. [ABSTRACT FROM AUTHOR]

The introduction of lightweight cutting tips in industrial wood machining could lead to machining at much higher speeds and thus greatly increase efficiency. One possible way to achieve this is through lightweight ceramic composites. An Al 2 O 3 ceramic matrix was selected and reinforced with particles resulting in a density of approximately one quarter of the currently used heavy tungsten carbide tools (density of >15 g/cm 3 ). Furthermore, a coating was applied to the ceramic cutting tools in order to increase the stability of the cutting edge. A combination of reduced coefficient of friction, frictional forces and a resulting decrease in temperature can lead to a reduction in chipping at the cutting tip. Chipping has always been the major drawback of ceramic cutting tools for industrial wood cutting. A ceramic composite containing 25 vol% of submicron and nano sized SiC particles shows good mechanical properties with HV 2 =21.5 GPa and K Ic =4.5 MPa m 1/2 . This composition performed very well in industrial cutting trials on laminated beech. The cutting performance was increased further by use of an industrially available coating on the tools. The quality of the cut wood surface has always been difficult to characterize when comparing cutting tool materials and is often performed qualitatively by experienced carpenters by touch. The surface quality of the machined laminated beech was for the first time quantitatively characterized using Gelsight 2.5D tactile sensing. [ABSTRACT FROM AUTHOR]

With the aim at performing the highest precision during woodworking, a mix of alternative approaches, fruitfully integrated in a common design strategy, is essential. This paper represents an overview of technical solutions, recently developed by authors, in design of machine tools and their final effects on manufacturing. The most advanced solutions in machine design are reported side by side with common practices or little everyday expedients. These design actions are directly or indirectly related to the rational use of materials, sometimes very uncommon, as in the case of magnetorheological fluids chosen to implement an active control in speed and force on the electro-spindle, and permitting to improve the quality of wood machining. Other actions are less unusual, as in the case of the adoption of innovative anti-vibration supports for basement. Tradition or innovation, all these technical solutions contribute to the final result: the highest precision in wood machining. [ABSTRACT FROM AUTHOR]