Analysis of the influence of the cutting edge geometry on parameters of the perforation process for conveyor and transmission belts

Abstract

Perforated belts, which are used in vacuum conveyor belts, can have significantly different mechanical properties like strength and elasticity due to a variety of used materials and can have different thickness from very thin (0,7 mm) to thick belts (6 mm). In order to design a complex machine for mechanical perforation, which can perforate whole range of belts, it is necessary to research the influence of the cutting edge geometry on the parameters of the perforation process. Three most important parameters, which describe the perforation process are the cutting force, the velocity and the temperature of the piercing punch. The results presented in this paper consider two different types of punching (a piercing punch with the punching die or with the reducer plate) and different cutting edge directions, angles, diameters and material properties. Test were made for different groups of composites belts – with polyurethane and polyester fabric, polyamide core or aramid-fibre reinforced polymers. The main goal of this research is to specify effective tools and parameters of the perforation process for each group of composites belts.

The influence of the piercing punch profile on the stress distribution on its cutting edge

“…As can be observed in both cases no defects common for the punching process (conicity or ovality of the holes, fiber pull-out, uneven edge or side surface, deformation of the covers of the belt, etc. [1]) have occurred. By analysing the quality of the side surface for both piercing punches we have received a very smooth surface with almost no defects.…”

“…Due to the variety of the construction, and as a result the mechanical properties of the polymer composite belts, which are subject to the perforation process ( Fig. 1), it is very difficult to design the universal tool for each type of belt [1][2][3]. Basically, we can distinguish three groups of belts: the elastic light belts with polyurethane, PVC or rubber core, which can be reinforced by fabrics, the rigid belts with increased strength, whose core is made of a polyamide film protected by polyamide fabric gaskets and the durable and rather flexible polyurethane belts reinforced with aramid fiber cord [2][3][4] (most common as toothed belts [5], but also as v-belt or round belt [6]).…”

Determination of the effective geometrical features of the piercing punch for polymer composite belts

“…The main focus in the presented research is put on the rigid belts with increased strength whose core is made of polyamide film covered by polyamide fabric protective gaskets and nitrile rubber (NBR) covers. According to the previous research presented in [4], this type of belts needs the highest perforation force and the quality of the hole strictly depends on the geometry and wear of the cutting edge, due to the combination of fabrics and rigid film in their structure.…”

The influence of geometrical parameters of the forming channel on the boundary value of the axial force in the agglomeration process of dry ice

“…The article presents the results of preliminary research on the influence of the geometrical parameters of the multichannel die on the limit stress value of the compaction process. Subject literature referring to different processes and materials indicates a significant relation between the geometrical parameters of the working system and the necessary force value to carry out the process under consideration [22][23][24][25][26][27].…”