Serebrennikov Yuri feature of our time is becoming more widespread use of metal structures in production, domestic violence, and especially - in the building. An example of this can be widely used metal fences and railings, metal furniture, metal frames and roof trusses buildings, elements of bridges, lighting poles and power lines, steel frame interior and exterior staircases, small architectural forms of metal, concrete reinforcement steel mesh products and fittings, metal doors, gates, grills and much, much more. Each of these products was originally composed of numerous elementary parts of metal, joined in the future into a coherent whole, and the most versatile, affordable and relatively simple way to perform permanent joints is by far the manual arc welding stick electrodes. This is understandable: Weld metal parts can be of any thickness, preparation of parts much easier, the process of welding a lot smarter than the alternatives - the use of bolted, riveted, glued and soldered joints. Weld seams can be in any spatial positions. The welding process requires a clearly appropriate qualifications, but is available to perform in living conditions, on-site and in the garage, does not require particularly sophisticated equipment - the trade is invited to enough welders consumer class. Durability and strength of the welded joint in most cases is not inferior durability and strength of the base metal. Continues to develop the technology of welding, both as the appearance of new welding equipment and the development of new types of electrodes - even more productive, providing the doping of the welding seam, the possibility of welding in awkward positions and from top to bottom, the welding of difficult materials such as stainless steel, cast iron non-ferrous metals. The correct choice of electrodes depends on the strength and reliability of the weld and seam, and therefore - all welded construction. It's about the electrodes and will be discussed in this article. Normal consumable electrode is a rod of steel wire (2-6 mm, but most often 3-4 mm in diameter) coated with special exterior coating. Despite the seeming simplicity of the coating of the electrode can be quite complicated, because This coating should provide a number of functions: stabilization of the arc, due to lower ionization potential in the arc zone, for which the coating composition is administered compound of potassium and sodium, a gas protection of the metal deposited through the formation of clouds of carbon dioxide enveloping the arc, for which the coating composition introduce organic matter and minerals - marble and magnesite; Restoration of molten metal from the oxide, for which the coating composition is administered to actively react with oxygen, calcium, aluminum, titanium, silicon, manganese, etc.; slag-forming components provide protection droplets of electrode metal, reduce their speed cooling and crystallization, contribute the exit from the melt of gas bubbles and non-metallic inclusions. For the doping of the weld in the coating is added chromium, nickel, molybdenum, tungsten, manganese, titanium, etc. To fix the coating on the electrode rods are used binders - water glass, gelatin, plastic. Plastic properties of the coatings provide additives-plasticizers - bentonite, kaolin, mica. The number of brands and types of electrodes is very large, but they differ in composition of the coating composition used wire, its diameter and length. Electrode length is usually 250-450 mm. Too inconvenient to work long electrodes, short - would have to change too often. The most common and most applicable to construction works are electrodes for welding low-alloy steels, a typical example of the type which are electrodes ELN and the SSSI and the newly developed electrodes SE-46-00. An example of cast iron electrodes can be electrode mark MOF-2. Technical Reference: Electrode SSSI 13/45 and 13/55 Purpose and scope - Welding of critical constructions made from carbon and alloy steels operating at low temperatures, when the weld metal increased demands on the ductility and toughness, as well as for welding of large sections. Coating type - basic (based on a mixture of powder fluorspar, marble, chalk, and ferroalloys). The disadvantage of such coatings is the tendency to form pores with increasing arc length, the presence of rust on the details, the application of moist (neprokalennyh) electrodes, as well - Reduced stability of the arc. The mechanical properties of the electrodes SSSI: Tensile-? 490 N / mm 2, bending angle weld ? 150 °; elongation-? 20%, toughness-? 128 J/cm2. Diameters: 2, 2.5, 3, 4, 5, 6. Electrode consumption 1,7 kg per 1 kg of weld metal. Kind of current - constant reverse polarity. Spatial positions of welding - any except for welding in the vertical section in the direction of the seam from top to bottom (where the molten metal and slag can leak at the site neprovarenny the electrode and interfere with welding.). The recommended value of the current (A) during welding electrodes SSSI 13/45 and 13/55 (mounted on the welding machine to weld): The recommended value of the current (A) Diameter of electrode, mm lower seam vertical seam ceiling seam 2.5 70 - 90 60-80 60-80 3.0 100-130 90-120 90-120 4.0 130-180 120-160 120-160 5.0 170-210 160-210 - Probe ANO-4 (type 46A) Purpose and scope - for welding of structures made of carbon steel with carbon content up to 0,25% and the tensile strength of at least 450 MPa. Coating electrodes ANO-4 - rutile (containing 50% titanium oxide as well - marble, talc, magnesite, ferro alloys, cellulose). Electrodes with such a coating allows to obtain a dense metal weld even if there is rust on the welded edges provide a slight splashing of electrode metal during welding, arc steady burning, have good technological properties. Kind of current - direct current reverse polarity or alternating current. Spatial positions of welding - any, except vertical down. Electrode consumption 1,7 kg per 1 kg of weld metal. The mechanical properties of the electrodes ANO-4: Tensile-? 460 N/mm2, elongation-? 18%, toughness-? 80 J/cm2. The recommended value of the current (A) Diameter, mm lower seam vertical seam ceiling seam 2.5 70-90 60-100 60-100 3.0 100-140 80-110 80-110 4.0 140-220 140 - 180 140-170 170-260 160-200 5.0 - 270-320 6.0 - - Electrodes SE-46-00 (type E46A). Some of the newest brands of electrodes, designed factory in 2004. They have the rutile and is designed for welding of important structures made of carbon and low alloy structural steels with a tensile strength up to 500 MPa., On alternating and direct current of either polarity in all positions. By extreme ease of ignition of the arc electrode is ideal for short run welds and weld root and root passes. When an alternating current requires only 50 V. The open circuit voltage. The electrodes are certified by the GOST R, NAKS, Maritime Register of Shipping Russian River Register. The mechanical properties of the electrodes SE-46-00: - Tensile strength 450 (46) MPa (kg/mm2), yield 380 (38.7) MPa (kg/mm2), elongation 24%, impact strength at 0 degrees . C 47 (4,8) J / cm 2 (kgf m/cm2). Electrode MOF-2 Purpose and scope - for welding, without preheating, welding and casting marriage surfacing of gray, ductile and malleable iron. Preferred for welding the first layer in the joints that require high density, as well as for welding joints, which make high demands on surface finish after treatment. Spatial positions of welding - in the bottom and vertical components, direct current reverse polarity. Electrode consumption 1,5 kg per 1 kg of weld metal. The recommended value of the current (A) Diameter, mm lower seam vertical seam 3.0 90-110 70-90 4.0 120-140 100-120 5.0 160-190 140-170 6.0 210-230 190 - 210
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