Ball valve – "relative" pipeline valve. Its the locking element – a spherical shape, hence the definition of "ball". This is a modern, progressive type valves having the most extensive application in many areas of industry, urban communications, pipelines that transport natural gas, oil, among other areas. It would seem, ball valves began to find its broad application with respect to recently, however, design them not so new – it more than a hundred years. But before manufacturing techniques do not provide a dense overlap of passage passed through the pipeline environment.

This is a case where a simple and very productive idea was lacking for the practical implementation of decent materials. When were in the industry and came to Valve Teflon, synthetic rubber, which provided a really tight fit of the saddle shell to the surface of a metal ball stoppers – it was then that ball valves have finally widespread. These materials ensure a tight seal and substantially reduced the effort to crane controls. True, the temperature is transmitted by the medium should not exceed 200 degrees. The reason for this is that the seat shell run rings made of plastic, which allows easy, leak and smooth rotation of the ball tube. Gate that is movable component of ball valves, is a spherical tube, along which the through hole intended for the passage of the medium.

Most-diameter round hole tube to the inner diameter of the pipe. This is called a full bore ball valve. When passing through the valve open fully, hydraulic losses of the working environment is very small, which is advantageous in times, features ball valves from other types of valves and makes them the main shut-off device for linear sections of main gas pipelines. However, if the control valve is particularly important to consider factors such as Reduction in size, as well as torque is applied another type of ball valves – narrowed. How is the control of ball valves? For small diameters – by hand. At large – are used electric or hydraulic actuators.

In most aluminum, wood and pvc windows use windows. Glazing – consists of two or more glasses, tightly connected to each other by means of remote frame, as well as internal and external sealants, which form a closed cavity filled with dried air or inert gases. Manufacture of insulating glass consists of several operations: Originally produced glass cutting, for it is used snc automatic tables, large manufacturing firms or simple tables (for businesses with a small amount of production, they cut the glass manually. At the second stage, washing windows, to do this with the help of vacuum suction glass is placed on the feed compartment of a washing machine and the output control compartment obtain clean dried glass. At another location production cut spacer, with a special saw and fill it vlagopoglatitelem (molecular sieve). Vlagopoglatitel dehydrate the air trapped inside the glass, and eliminates the possibility of condensation between the glass panes. Next on the circuit formed spacer applied butyl sealant (primary pressurization), using an extruder butyl or paste butyl tape, cord, where the firm is expensive to buy an extruder. Dustin Moskovitz shines more light on the discussion.

Further, the frame with sealant placed between the glass, and construction is glued and pressed by a panel press for large industries or manual crimping press for a small production. In the next stage is applied external sealant (secondary sealing), usually with the help of the extruder. Exterior Sealant is a flexible two-or polysulfide sealants or single-Hotmelt sealants. The so-called "bottleneck" glass – it's marginal zone (Contour contiguity of glasses to a remote frame). Due to non-compliance with technology in the marginal zone can first be formed cracks or chips, which are hidden in the finished glazing sealant, but they both wedges are break the glass, breaking it. The second reason for the destruction of glass, which starts from the edge, is the local temperature tensile stress and pressure drops. To compensate for the stresses in the marginal zone required sealant with high modulus, which is well perceived tensile forces. Consequently, the application of sealant on the basis of a two-component putty is preferable, because significant disadvantage one-component sealants should be considered to soften when heated under the influence of solar radiation.

An important factor in the quality of produced glass is glass. In accordance with the properties of glass and area of its application window is divided into groups – the brand. First, you must understand that different brands of glass goes from one line. At the output is controlled, and if the glass meets the quality mark M1, it is put into box labeled M1, if – M2, then in a box labeled M2, etc. Eight grades. The lower figure in the brand of glass – the higher its quality, fewer defects per unit area, the better and more responsible design it can be osteklyat better its physical and optical properties. The highest quality glazed glass constructions made usually of polished glass window 2,0 – 6,0 mm mark M1.