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  • Author: Andrzej Jakubowski x
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Abstract

The product from porous permeable material based on a wire coil consists of a round, porous, thin-walled tube. The impact of assembly loads of the porous tube has been examined to determine the maximum values of the compressive force and axial elastic strain during the assembly. To improve mechanical properties of the product additional reinforcement has been proposed: larger diameter wire, woven wire cloth or spring.

Abstract

The technology of producing the current contact connections on the superconductor cable edges is presented. This lead cable is used as one of the major elements of the magnetic system in thermonuclear reactor construction, actuality for modern world energy. The technology is realized by the radial draft of metal thin-walled tube on the conductor’s package. The filling of various profiles by round section wire is optimized. Geometrical characteristics of the dangerous crosssection (as a broken ring) of thin-walled tube injured by the sector cut-out are accounted. The comparative strength calculation of the solid and injured tubes at a longitudinal compression and lateral bending is acted. The radial draft mechanism of cylindrical thin-walled sheath with the wire packing is designed. The necessity to use the nonlinear theory for the sheaths calculate is set. The resilient co-operation of wires as the parallel located cylinders with the contact stripes of rectangular form is considered.

Abstract

Original experimental technical equipment for making samples in the form of permeable tubes of porous material, i.e. coiled wire. The article describes the construction of the equipment, the processes of forming and pressing the wire semi-product and methods of fixing the ends of the wire product.

Abstract

The details of making technology of porous permeable material with use of wire are allowed to carry out the analytical research of structure and structural characteristics of wire winding body. Its permit for prognostication the final properties of material, that is produced by the following deformation treatment (diameter reduction). Due to the regular organized arrangement of wire, the coil of winding body is considered as a multispan continuous beam, but a contact of coils - as interaction of two cylinders. Possibility of exactly calculation of the contacts between coils is allowed to go over the single fragment displacements into deformation of whole winding body. During research of deformation processes in regards of winding body geometry and used wire mechanical properties, the structural characteristics of porous permeable wire material are expected. The optimal number of winding layers, eliminating the distortion of organized final structure, is established. The material pressure-compactness relation is obtained in order to control the technological conditions of winding and drafting for guarantee the product required properties.

Abstract

Load bearing system simulation is provided for a huge lathe to be renovated. Static and modal analyses are done by FEM. Focus was centerline rising, needed for larger rotor shaft machining. Forces between shaft and three supports were applied. Shaft static stiffness is lowered at 1.15 times only for 600 mm centerline rising. Supports have lost its rigidity at 1.42 times. Concrete pouring into bed cavities is recommended for supports flexibility limitation such as tailstock reinforcement. Robustness of bottom resonances is revealed both for rotor shaft (14.5–18.2 Hz) and supports (42.7–55.4 Hz). Centerline rising is allowed on 300 mm at least. It gives possibility to machine extremely large (up to ø2750 mm) shafts.

Abstract

Results of research on the hazard posed by polycyclic aromatic hydrocarbons contained in the dusts emitted from motor vehicle braking systems have been presented. The polycyclic aromatic hydrocarbons (PAHs) constitute a group of chemical compounds that pose a serious danger to the human health, chiefly because of their carcinogenic properties. Investigations into the issue of environmental pollution with polycyclic aromatic hydrocarbons generated by motor vehicle traffic were carried out in connection with the work being done at PIMOT on systems to reduce dust emission from motor vehicle braking systems. The investigations included determination of PAH contents of the dust emitted from vehicle braking systems as well as the PAH concentrations in the indoor air in a room with the stand for testing dust emissions from braking systems and in the duct to carry away gases from that room. Moreover, the PAH contents of soil were measured in the context of location of the soil sampling points in relation to traffic routes. The PAH contents were measured in Warsaw and in Zabrze. The investigation results confirmed that PAHs considered as being most harmful to the human health due to their carcinogenic properties were actually present in the dusts emitted from braking systems. The PAH contents of soil were found to be very sensitive to the location of the soil sampling points in relation to traffic routes and this is a confirmation of the thesis that motor traffic is an important source of environmental pollution with polycyclic aromatic hydrocarbons.