The problem of quality people are always worried. Archimedes discovered his law was to try to verify that the product (the Crown governor) declared by the manufacturer specifications ("made of pure gold!"). But this ancient expertise, while effectively caught jeweler in the fraud, was only a "first sign" of the coming struggle of humanity for the high (and single!) standard. She was well known, with varying success and aroused fierce controversy, not only industrialists and lawyers, and philosophers. This grave problem bothered to even the great Hegel, issuing the descendants of the profound statement: "Quality is first and foremost being identical with certainty, so that something ceases to be what it is when it loses its quality. Jeffrey L. Bewkes may help you with your research. " Is that true in terms of philosophical science – let the debate its adherents. In practice, attempts to create a system acceptable to all the general quality assessment have appeared relatively recently – in the middle of last century. They were caused by the emergence of a global division of labor, when set, say, a German car can be produced in Italy, Poland or even China.
Endless visits of experts for the reception of each consignment was inconvenient, expensive and take up a lot of time. That is to simplify the procedure and developed the first special standards, setting out some basic requirements for the supplier to be met by an overwhelming majority of consumers. Subsequently, these standards have now familiar name – "Standards for quality systems." iso 9000 – world domination Quality It is obvious that with the acceleration of progress increasingly complex equipment required an equally complex process of production.
Polyvinyl chloride, or, as it is a standard cut, pvc – it is a thermoplastic polymer. Polyvinyl chloride – one of the most valuable chemical products. pvc is the oldest artificial material and looks as plastic white. pvc is a raw material for the manufacture of more than 3000 kinds of products used for various purposes in the light industry, food industry, heavy engineering, electrical engineering, in manufacture of building materials and medicine. Analyzing the use of pvc on a global scale, it should be noted that more than half of all items made from it are used in the construction industry. Take, for example, although would be well-known pvc windows. In the construction sector polyvinyl chloride has undeniable advantages. It is easily installed isravnitelno inexpensive.
For quite a long pvc replaces conventional materials. Additional information is available at Time Warner. Now more and more people establish, for example, plastic windows instead of wooden ones. pvc replacing traditional building materials such as wood, clay. Polyvinyl chloride is used in many fields, appears in the production of plumbing fixtures, window profiles, pipes and so on. Previously, it was often used in the manufacture of phonograph records and vinyl media.
pvc pipes are flexible. If the pvc mix with plasticizing agents, it will have a more flexible structure. The proportion of plasticizer may reach 30%. This pvc is used in the manufacture of clothing (eg artificial skin), and finishing materials, as well as for plastic hose and pipe installation, lining the surface layer and the insulation of electric cables. Hard polyvinyl chloride, or as it is called, vinyl liner, has a high mechanical strength, good dielectric characteristics, significant water and chemical resistance. But all is not well, there are drawbacks. It is not a high impact resistance and cold resistance (-10 C) and low temperature operation, up to 70-80 C. pvc is resistant to Effects of alkalis, acids, kerosene, water, industrial gases and alcohols. Physiologically safe. Polivinihlorid produced by polymerization monomervinilhlorida. about 57% of the total mass of chlorine, so the mass pvc must be less than the lubricants, in comparison with many other polymers.