The economizer is a modern boiler's necessary part. Its function is to heat the water by using the gas heating, reduces heat loss due to exhaust. At present. Now, cast-iron economizer was still used. Although its inoxidizability is strong, the maintenance cost is low, but the volume is big, the weight is big, the cast iron crisply, it can not to be able to withstand the pressure surge, . And it has too more flange. It was easy to present the water leakage phenomenon. And it only uses in the working pressure being lower than 2.4MPa on the boiler. It can only make the non-ebullition type economizer. Although the bare tube type economizer 's weight is light, the volume is small, but the heating surface is small, the heat transfer effect is bad. For this situation, Our company digested the new product which has the high strength and high performance. This economizer has been used in the large-scale boiler. It also has the good use effect.