drywall screws coarse

The welding core is the metal core of the electrode. In order to ensure the quality of the weld, there are strict regulations on the content of various metal elements in the weld core. In particular, there are strict restrictions on harmful impurities (such as sulfur and phosphorus), and the quality of the weld core metal should be better than that of the base metal. Arc welding cannot be carried out on a smooth rod without a coating. This is because the arc stability is very poor, splashing is very large, and the weld is not well formed. After long-term practice, it is gradually found that the performance of the electrode is greatly improved by coating the welding core with some mineral raw materials (i.e. electrode coating). (1) Ensure stable arc combustion, so that the welding process is normal. (2) Using the gas produced after the drug skin reaction, protect the arc and the molten pool, prevent the harmful gases in the air (such as nitrogen, oxygen, etc.) from invading the molten pool, such as these gases will cause cracks and pores in the welding material, so that the welding can not achieve the ideal effect. (3) After the drug skin is melted, slag is formed, which covers the weld surface to protect the weld metal, make the weld metal slowly cool, help the gas escape, prevent the generation of pores, and improve the structure and performance of the weld. (4) After melting, various metallurgical reactions will be carried out, such as deoxygenation, sulfur removal, phosphorus removal, etc., so as to improve weld quality and reduce alloying element burning loss.

Generally, galvanized wire used for welding is required to have a certain hardness. After acceptance of galvanized wire, the first thing to do is to feel the hand, and the other thing is to test on the machine. Because the average user does not have testing equipment, it is also very inconvenient to test on the machine. Use a micrometer to measure the diameter of galvanized wire evenly, and keep it about 0.02mm above and below the contract signing standard, with neat appearance, no leakage plating and no mess.

Barbed rope is an isolation protective net made of iron wire, which is wound on the main line (twisted wire) through the winding machine and through various weaving processes. Thorn rope generally has three methods of twisting, the following Haorong for you to introduce in detail.

The life of the “wire”, is actually “low carbon steel wire”, carbon content in less than 0.2%. The surface is usually coated with zinc plating because it is easy to rust. Under atmospheric conditions, the galvanized layer will not rust before most of the fall off, relatively soft. The life of the “steel wire”, is carbon content in about 0.6% of the “carbon steel wire”, or carbon content in about 0.8% of the “high carbon steel wire”, they have enough hardness and elasticity after appropriate heat treatment, high strength. Uses such as winding ordinary spring and so on.