Welding Wire is a kind of metal product. Although most of the surfaces of cored wire and seamless
Flux Cored Wire are copper plated, the surfaces of some seam cored wires are rust proof (such as chemical blackening)..
In addition to plastic bags, all the bags are packed with a moisture-proof agent, which is wrapped in paper boxes. However, moisture-proof is still a problem that must be considered in the management of
Welding wire protection. Because it is a hygroscopic welding wire, the content of diffusible hydrogen in the deposited metal can be increased, resulting in pits, pores and other defects. The welding process performance and mechanical properties of the weld metal become worse, which can lead to weld cracking strictly, which is the same as other welding materials.
Of course, since the powder in the drug cored welding wire is tightly wrapped in the steel strip, the drug powder is in contact with the air very much, and at the same time, the water glass in the electrode is not used as a moisture absorbing substance.
Therefore, compared with the welding rod, the amount of moisture absorption of the welding wire is very small. However, if the welding wire is placed in a high temperature and high humidity environment for a long time, it will also absorb moisture except for rust on the surface of the welding wire.. With the increase of moisture absorption time and amount, the amount of diffusible hydrogen in the deposited metal gradually increases, which answers that the tear resistance of the weld is unfavorable.
Management requirements for welding wire
① It is required that under the recommended storage conditions, the original unpacked welding wire can be kept "fresh in the factory" for at least 12 months. Of course, the maximum storage time depends on the ambient atmospheric environment (temperature, humidity, etc.).. Recommended storage conditions of the warehouse: room temperature is above 10~15 ℃ (the highest ℃), and the maximum relative humidity is 60%.
② The welding wire shall be stored in a dry and well ventilated warehouse. It is not allowed to store it in the open air or indoors with harmful gases and corrosive media (such as SO2). The interior shall be kept clean and tidy. When stacking, it should not be directly placed on the ground. It is better to place it on the shelf or base plate that is not less than 300mm from the ground and wall to protect air circulation and prevent moisture.
③ There are many welding methods and steel types applicable to the welding wire, so the shape of the welding wire coil and the bundling status are various. According to different wire feeders, the shapes of rolls can be divided into disc, bundle and cylinder. Therefore, during the transportation, it is necessary to avoid littering and packing damage. Once the package is damaged, the welding wire may absorb moisture and rust.
be careful
Bundle welding wire shall not be loaded into wire feeder to prevent deformation of wire rack.
Cylindrical welding wire shall not be rolled during handling, and the container shall not be put down or tilted to avoid winding of welding wire in the cylinder and hindering use.
Management of welding wire in use
① The welding wire shall be used up within 2 days after unpacking.
② After unpacking, the surface of the welding wire shall be protected from condensation and condensation, and some of it shall be polluted by rust, grease and other hydrocarbons, so as to protect the surface of the welding wire from being clean and dry.
③ When the welding wire is used up and needs to be put in the wire feeder overnight, the wire feeder (or wire reel) shall be covered with canvas, plastic cloth or other articles to reduce the contact with moisture in the air.
④ The welding wire that cannot be used for more than 3 days shall be removed from the wire feeder. Put it back into the original package, seal it, and then put it into the warehouse with good storage conditions.
Quality management of welding wire
① Each batch of welding wire purchased shall have the manufacturer's quality assurance certificate. The qualified products must be accompanied with product manual and inspection certificate in each package. The inner package of each welding wire shall be marked with a label or other methods to indicate the welding wire model and corresponding national standard number, batch number, inspection number, specification, net quality, manufacturer name and former address.
② The welding wires shall be stacked separately according to their types and specifications to prevent misuse.
③ The welding wire shall be handled according to the principle of "first in, first out" to minimize the storage period of the welding wire.
④ If the package of welding wire is damaged, it shall be carefully checked. The welding wire with obvious mechanical damage or excessive rust trace shall not be used for welding. It shall be returned to the inspector or technical debtor for inspection and use approval.
Drying of welding wire
Drying is a common problem in the use of welding rods, but for welding wires, there is no clear mention in the existing literature and product descriptions. This shows that it is usually unnecessary to dry the welding wire before welding.
In the actual construction, some people think that the welding wire which is strictly affected with damp can also be dried, but the temperature should not be too high. Generally, it can be dried for 1~2h at 120~150 ℃. This is beneficial to the elimination of pores and the reduction of diffusible hydrogen content.
