Brief description of the power cable Power cable AnBn AnBn used for transmission and distribution of electric power in stationary installations for AC 10, 20 and 35 kV nominal frequency of 50 Hz and used networks with grounded and isolated neutral. By design, performance and operational characteristics, the cable corresponds to international standard IEC 60502-2 and harmonization document HD 620 S1.Konstruktsiya power cable Cable AnBn AnBn multiwire phase conductor has a circular shape made of copper or aluminum, corresponding to the class 2 according to GOST 22483-77. Conductor screen imposed by extrusion of an electrically peroksidnosshivaemoy polyethylene composition, then a layer of insulation peroksidnosshivaemogo polyethylene and another screen in isolation. This is followed by a layer of electrically conductive polymer or paper tape minimum thickness of 0.2 mm, imposed by the winding, and on it – annealed copper wire nominal diameter of 0,7-2,0 mm, over which is superimposed spiral copper tape with a minimum thickness of 0.1 mm. The minimum width is 8 mm. For insulated cables provides a separation layer of two strips of crepe paper or a cable with a minimum thickness of 0.15 mm, top – the shell of polyethylene. For three-core cables by twisting a core around a bundle of unvulcanized rubber or PVC.
As the interfacial fill applied uncured rubber compound melonapolnennaya or highly filled polivinihloridny Plasticized. The shell is made of polietilena.Tehnicheskie and operational characteristics of the power cable Power cable AnBn AnBn operated at a temperature of -60 C to +50 C and relative humidity up to 98% (at temperature +35 C). Limiting long-term exposure temperature heating cables in a live operating conditions + 90 C, in an emergency mode or overload, it is + 130 C (with a duration of heating no more than 8 hours per day and 1,000 hours for lifetime). Short-circuit (up to 4 seconds), the maximum permissible temperature of the heating cable conductors + 250 C. Gasket and mounting cables AnBn without pre-heating is carried out at temperatures below -20 C. Minimum bending radius of single core cables 15 Dn, three-core – 10 Dn (Dn – outer cable diameter). Construction stipulated cable length when ordering. The warranty period of the power cable AnBn 5 years, lifetime – 30 let.Sfera use a power cable power cables AnBn AnBn designed for use when laying in the ground of any corrosion activity on the highways without difference in levels.
Paved with stones of the road extended from time immemorial. Even the Greeks but the Romans used for road stone. After all, they knew about its properties, such as practicality, strength and durability. The first time the stone was left as is, but over time began to process and grind. So there was sett. Today, the use of stone as the material is not lost relevance, and morphed into a completely different species and sizes. David G. DeWalt is likely to agree. In an age of new technologies and universal normal progress of the stone came up with less costly and less severe alternative – a concrete paving stone, better known as Pavement.
Production of paving slabs are a few notable Technology: vibrocasting and, of course, hyper. s for Diseases Control and Prevention has much to offer in this field. The method of compaction is concluded that the compaction of concrete mix in the form of technology produced by excessive pressure on the press. Positive traits of this technology is a major share of automation, increased productivity, and make the prospect of this tile is colored layers. Paving slabs, produced by hyper-technology, has a high wear resistance, through the use of concrete with water cement ratio and low use of a special steaming procedure. In addition, vibropressing tiles for sidewalks shall be chipped surface, which makes it convenient for use in icing. The life of a tile is large enough and up to 20 years. And most of the tile is made solely on the technology vibropressing.
Casting method is by vibration of a special solution in a special form on vibrator. Method of low productivity and there is no automation. Pavers, obtained by this method shows several small characteristics than the first. This Pavement has a very smooth surface that does not "breathe", which will lead to cracks in the freezing point of water in it. Solution used for casting, has a high ratio of cement and water, which reduces wear in the winter tiles and significantly increases the costs of building. Although the cost of machinery and equipment used for the method, rather less than the hyper. Condition good styling and long term condition of the tiles for pavements and there will be ideally prepared foundation. Paving surface should be professionally marked, and at the same level and the slope is strictly for the water runoff. Of course, on how to use and changing the thickness of the tile. The greater the load on the outer surface, the thickness more. Paving slabs in thicknesses from 40 – 45 mm laid out on a dry mix or mortar bed at gravel pad, mass transport vehicle. Products in height from 45 mm race survive in a big machine. Laying paving slabs by using the road and curbs. There are two types of borders – two-and one-sided. More than any used size – 50, 20 to 60 (in cm). To date, developed a large number of schemes and laying a huge variety of colors of paving slabs that can satisfy any decision on paving site. We have paving slabs used in the construction of terminals, platforms, walkways, sidewalks, parking lots, bus stops. And every year the place of tiles increases. Maybe soon it will replace the almost all normal surfaces, because such a tile – it is the cleanest, tech and environmentally friendly material.