Research on current status of water heater tank welding

Abstract: This paper introduces the materials of various water heater water tanks (commonly known as liners) and the welding methods used, and introduces the materials and welding methods of gas water heater water tanks, solar water heater water tanks, electric water heater water tanks and heat pump water heater water tanks. The welding process of solar water heater water tank and electric water heater water tank is discussed, hoping to provide a reference for everyone to understand the manufacture of water heater water tank.

Key words: gas water heater; electric water heater; solar water heater; air energy heat pump water heater; water tank; liner; welding

Foreword:

A water heater, as its name suggests, is a device that provides hot water. From the heating method, the water heater can be roughly divided into two types of hot water heaters and heat storage water heaters. The water heaters on the market now mainly include gas water heaters, solar water heaters, electric water heaters and air energy heat pump water heaters. Among them, solar water heaters, electric water heaters and air energy heat pump water heaters are all heat storage type water heaters; gas water heaters are typical instant water heaters, and fast heat type electric water heaters are also instant water heaters.

The water tank (ie, the heat exchanger part) of the gas water heater is made of aluminum alloy and pure copper. The water tank of the solar water heater (commonly known as the inner tank) also has two kinds of conditions. Generally, the water tank of the non-pressure-bearing solar water heater is austenitic stainless steel; the water tank of the pressure-type solar water heater is made of low-carbon steel post-weld enamel, and some parts are also austenitic. In the form of stainless steel, nano-polymer materials (nano-polypropylene modified resin) have emerged in recent years. The electric water heater water tank is mostly made of low carbon steel (cold rolled steel) post-weld enamel (Qingdao Haier electric water heater liner with hot-rolled pickled steel RST330), austenitic stainless steel and hot-dip galvanized water tank, in addition to the electric water heater The crystal liner (the crystal liner is a liner made of a combination of a bearing layer and a leak-proof layer of the inner liner), and the pressure-bearing layer is made of a 1.2 mm to 2.0 mm thick cold-rolled steel plate to form a leak-proof layer. The special synthetic polymer material passes through the steel crystal integration process to completely integrate the entire inner surface and the opening of the inner liner without any weld seam, so as to form a liner without weld seam. Since the color after the formation is generally white jade color similar to crystal, it is called a crystal "inner". "Crystal" is a special synthetic polymer material. It has a long-term comprehensive ability compared with the commonly known engineering plastics such as ABC and polycarbonate. It is almost insoluble in any solvent (such as alcohol, below 100 °C). Gasoline, methanol, strong acid, strong alkali), so its anti-scaling effect is particularly outstanding. However, the formation process requirements are high, and each process of the manufacturing process is required to be strictly controlled). The air energy heat pump water tank is mainly divided into pressure-bearing type and non-pressure-bearing type. Among them, there are two kinds of pressurized water tanks: stainless steel pressurized water tank and enamel pressurized water tank. At present, most of the products in the air energy heat pump water heater market are stainless steel water tanks. All kinds of water heater water tanks (liners) generally need to be welded (except nano-polymer materials), but the welding process used is different.