In Europe, since 2003, introduces single 'European standards illumination en 12464-1', detailed in the different countries in accordance with national conditions. In European regulations with regard to the following lighting parameters: * The illumination zones of visual performance * The illumination problem areas of the immediate environment * A generalized index of discomfort * Colour rendering index * Ripple illumination for workplaces with computers, in addition, regulated by limiting brightness lamps, reflected on the screen. The first two parameters describe the quantitative aspect of lighting, the other three – quality. We consider each of the regulated parameters. 1. Illumination band performance of visual tasks. Instead of general lighting of the premises, regulated by the same rules are now standardized illumination directly in the area perform visual tasks, ie in the workplace. This may be a desktop or just part of it.
Depending on the type of work performed in the area of illumination performance of visual tasks can be from 200 to 750 lux. In some areas lighting should be adjustable (conference rooms, meeting rooms, etc.). In areas where a large proportion of employees working with computers, normalized maximum brightness of lamps that can be reflected on the screen. For computers the old generation with the screens on the cathode-ray tubes without anti-glare coating, this brightness at an angle of 65o should not exceed 200 kandel/m2, for computers with lcd screens or with anti-reflective coating – 1000 kandel/m2. Light sources are constructed on the basis of light-emitting diodes have the angle of 15 to 120 degrees.
included in the device to improve the accuracy of cut and cutting thin strips (optical cutting line illumination, etc.), is also a feature of this type of devices. Guillotine cutter is the most difficult type described here, the cutters – guillotine. This precision equipment is not afraid even the average circulation of paper products. They exist as electrically driven, which helps improve productivity and quality of the cutting operation, and the most simple mechanical. Highlighting the cutting line is the main option of this type of equipment for cutting paper. It should be noted that all the cutters, usually equipped with high-quality stainless steel knives. And the fact that the guillotine blades and saber cutters and easy to change and sharpen should be attached to yet another positive quality of this type of technology. And in the case of blunting the roller cutter blades should completely change the cutting head.
Stopping their choice on one way or another cutter, it is necessary first of all, know the purpose of buying it. It is no secret that the design and practical features inexpensive and Reciprocating roller cutters have several disadvantages, which can greatly complicate or even make it impossible to implement the conceived plans. For example, the roller cutters because of their low efficiency are used primarily in specialized purposes or as a support tool. Reciprocating cutters are also able to deliver much of a hassle. They are very difficult to obtain high-quality slice of the construction and design, despite the impressiveness of the structure floor models.
Cropping occurs curve. The most noticeable is the high stack of paper. A shaggy edge trimmed production comes from the fact that the paper is exposed to mechanical strain. Certainly, there are ways to reduce these negative phenomenon, but just to remove them – you can not. Moreover, Reciprocating cutter knives are quite complex in sharpening, sharpening is therefore very serious money, as are the new knives. Therefore, the choice in favor saber cutter should know about these nuances. Often saber paper cutters are used only as an accessory. Not as basic. Most advantageous to look guillotine cutters, because their design follows the professional shredders.
In some cases, to expand the technological capabilities of arc welding advisable to use a mixture of argon and helium. Addition of helium to argon promotes proplavlyayuschey ability of the arc and improves the seams. Widely used mixture of argon and active gases following compositions: 1.Smes Ar + 10 30% N2. Addition of nitrogen to argon also enhances the ability of proplavlyayuschey arc. This mixture is used for welding copper alloys and some grades of austenitic stainless steel. 2.Smes Ar + 1 5% 02. The admixture of oxygen to argon lowers the critical current at which the droplet transfer of electrode metal passes into the jet, which allows to increase slightly welding productivity and reduce splashing of the metal. mixture used for welding carbon and alloy steels.
3.Smes Ar + 10 20% C02. Carbon dioxide for welding mild and low-alloy steel helps eliminate porosity in welds. Addition of C02 to argon increases arc stability and improves the seam for welding sheet steel. 4. mixture of 75% Ar – 20% C02 – 5% 02 provides high arc stability when welding consumable electrode, the minimum spraying metal, forming a good weld, the absence of porosity. 5.Smes Ar + 10 20% H 2 is used for microplasma welding. The presence of hydrogen in the mixture compresses the plasma column, making it more concentrated. In addition, the hydrogen creates a zone of welding required in some cases reducing atmosphere. In the absence of ready-made gas mixtures of gases can be mix to the welding station. The composition of the mixture supplied to the burner is adjusted by changing gas flow in the mixture.