Powder coating firmly established in our lives – is all around us things that have passed this procedure. Compared with more traditional methods of powder coating technology has a number of advantages. For example, the preparation of the dye does not require solvents, which makes the production of safer, more environmentally friendly, fast. Powder coating uses a dry matter, tiny particles which are deposited on surface with a stream of compressed air. On the structure of these particles are thermoplastic or thermosetting polymers. When heated (and drying at high temperature – an essential element of the process powder coating), the substance melts and forms a high-impact resistant layer. Mashables opinions are not widely known. This ensures the reliability of powder coating. Dry paint, which uses this technology may differ by properties and structure.
Typically, when using high quality materials and compliance with all requirements of the process works, powder coating can withstand considerable temperature differences and is used in most harsh conditions. However, some types of paints have a more robust and can withstand heat up to 120 degrees. Thanks to these properties, powder coating has become an ideal method of creating vandal-proof and extremely durable coatings. In particular, it is the technology of powder coating is used for example in the automotive and aviation industries. Pipes modern oil and gas pipelines are also covered with using powder coating. However, items that have passed this procedure can be found in everyday life. Moreover, powder coating is today one of the most popular technologies for decorative and protective coatings. And if initially it was used only for work with metal, it is now applied, and powder coatings on glass, and stone (imitating the more expensive breeds), and even a tree. Of course, for each new material has to make some adjustments in the technology, but progress does not stand still, and every year the powder coating is becoming more accessible, easier and more versatile.
Vanny welding technique used in welding steel reinforcement bars of diameter 20-100 mm, the joints of multilane reinforcement of concrete structures, joints flanges bent from the fringes of large cross section, as well as other details. For Welding vannym way horizontal bars use a special steel molds. The shape is welded to the metal interface and remains on the rod after completion of welding. Before welding the ends and sides, the surface of all smooth out the rods with a steel brush. The gap between the rods should be 1,5-diameter electrode (coated). The discrepancy between the axes of rods shall not exceed 5 / o the diameter of the rods. Also used copper shapes, removed after welding. Initially melted bottom wall form and weld it to the edges of the bars without the addition of welding rods.
Gradually, producing oscillatory motion perpendicular to the axis electrode rods all section of the joint. Excess slag is removed from the bath scoop. Metal bath should be kept in a liquid state to the ends of the rods to fuse with the metal bath. After welding, the arc of a half section of the joint direct mainly on the middle part of the bath, reducing the heating of the ends of the rods. To prevent the formation of a joint piping give him a thickening of 2-3 mm in height. To increase the deposition rate, lower bath temperature and reducing the amount of slag in arc welding additional steel bars are introduced.
Linear displacement sensor is designed to control movement of various objects, goods elevator cabs, hydraulic lifts in the loading system, etc., that is, in systems that require accurate information on the status of the object during its motion. By way of removing the information of linear displacement sensors are divided into contact and contactless. In turn, divided into proximity sensors with mobile mechanical parts and do not have. Optical and infrared sensors of linear displacements are non-contact and have no mechanical moving parts. Inductive and magnetic sensors of linear displacements are non-contact, but with mechanical moving parts. By contact is resistive sensor. The main characteristic of all types of sensors is to determine the absolute position, movement and speed. To obtain Information from sensors is used RS-485 interface.
Maximum cable length by which one can transmit a signal up to 500 meters Operating temperature -40 C to +60 C. Measured path length from 1 mm to 5000 mm (or 10 000 mm). Individual attention deserves a special series of non-contact electronic sensors Start Electron.com (SE Series) designed for hydraulic mechanisms, where the sensor is operating in harsh conditions with environmental stresses. K advantages of these sensors are: high accuracy of measurement of the distance measured by the protection system from external influences, including vibration; ease of use, a high degree of dust and moisture protection the point when power is off, long service life – due to non-contact measurement method, a high linearity, repeatability and resolution;
When welding high-alloy steels and alloys is difficult to ensure stability of the weld metal and metal heat-affected zone in the formation of cracks and corrosion resistance of welded joints, to preserve the properties of the weld metal and weld time under stress and high temperatures, getting tight joints. Technological features of welding high-alloy steels due to their physical properties. Reduced thermal conductivity and high electrical resistance (approximately 5 times greater than that of carbon steels) contribute to the higher rate of melting metal, a greater depth of penetration and deposition rate. Reduced thermal conductivity and high coefficient of linear expansion are responsible for enhanced buckling of structures by welding. Therefore, in the arc welding processes to produce modes with lower values of current and heat input power at smaller departures electrode greater speed of its delivery as compared with welding carbon steels. One of the main tasks of technology arc welding of high alloy steels and alloys is to ensure uniformity of chemical composition on the length of the seam and its cross section, which is achieved by maintaining strict consistency welding conditions. With the mechanized method is easier to ensure consistency of welding regime and the stability composition, structure and properties of the weld metal.
Therefore, in the manufacture of structures made of high alloy steels and alloys should strive to achieve maximum mechanization of welding processes. To prevent the intoxication of the alloying elements and protection from the interaction with the air additional requirements – welding in an inert environment, the use of coatings and fluxes, welding short arcs, provides the best results automatic welding. For welding high-alloy steels and alloys using manual metal arc welding with covered electrodes, manual, mechanized and automatic welding in protective gases, submerged arc welding, electroslag. Welding with covered electrodes operates at reduced compared with welding carbon steels currents, the dc reverse polarity, without transverse suture needles swing, short arc. Using basic coated electrodes with a rod of wire, appropriate brand welded steel with light indicator weldability and performance requirements. For example, when welding chromium-nickel steel to prevent the formation of hot! cracking and intergranular corrosion using electrodes such as E-04H20N9 (Brand CL-11) or E-02H19N9B (RLA-7), providing a weld austenitic-ferritic (2,5-7% ferrite). Submerged arc welding used to connect to a thickness of 3-50 mm. Compared with welding carbon steels to high alloy steels by 1,5-2 times reduced flight electrode, used electrodes with a diameter of 2-3 mm, welding, multi-layered, at a constant current of reversed polarity with fluxes (ANF-14, AN-26, etc.).
The big advantage of submerged arc welding in comparison with the manual, along with increased productivity and quality of connections is to reduce costs associated with the partitioned edges. Welding in protective gases is carried out in inert gases, consumable and consumable electrode is continuously burning and pulsed arcs. tig tungsten electrode is used for details of the thicknesses of less than 7 mm and for welding root passes. Welding consumable electrode operates in argon, as well as in mixtures of argon and helium is used and a mixture of argon and oxygen and carbon dioxide. Welding consumable electrode operates on the current strength, which provides inkjet transfer of the metal electrode.