Welding drug skin by a variety of raw materials, in accordance with the main component of the drug skin can determine the class of electrode coating Yin. For example, called ilmenite type of drug skin towel ilmenite; scoop drug skin contains titanium dioxide and 30 do more than 20 do the following calcium, magnesium carbonate, known as titanium calcium type. Only low hydrogen type exception, the rejection of natural medicine skin Cao is mainly composed of calcium, magnesium carbonate, and fluorite, but the lowest amount of hydrogen in the weld as its main feature to be named. No drug skin types, use the binder for the potassium silicate (potassium-based potassium and sodium water glass〗 or sodium silicate, the same drug skin types can be further classified as potassium-and sodium , such as low hydrogen potassium type and a low hydrogen sodium plastic. the former can be used for AC and DC welding power source, while the latter can only use the power of the night flow.
 Electrode medicine skin type classification are shown in Table 1-9.
Table 1.9-electrode type of drug skin.
Note: when low hydrogen type coating containing large amounts of stable arc agent 丨 can be used for AC or DC.
Low carbon steel electrode, for example, Table 1-10 lists the typical electrode medicine skin formula For example, Table 1-11 lists the chemical composition of a variety of Welding Rod slag, Table 1-12 lists the chemical composition of the various electrode drug skin . It can be seen from these tables due to different components of drug skin formula, resulting in a variety of drug skin type electrode welding performance, the characteristics of welding slag and weld metal mechanical properties are different. The characteristics of a variety of drug skin type electrode will be elaborated in chapter 6. The graphite type coating, mainly used for cast iron WeldingElectrode and some surfacing electrode; base-type drug skin used for aluminum and aluminum and other nonferrous scrap electrodes.
Example of Table 1.10 Typical electrode medicine skin formula