It is made of high-quality aluminum block and cast by high-temperature melting, high efficiency, energy saving, uniform heat distribution, excellent thermal conductivity, good heat preservation performance, corrosion resistance, and anti-magnetic field; the heating ring adopts a concave-convex air groove structure design to prevent the use process The temperature of the inner heating tube is too high, which prolongs the service life of the electric heating coil; the semicircular fixing mode is adopted, which is more convenient for installation. Used in injection molding machines, extruders, widely used in various types of machinery, molds, pipelines, chemicals, rubber, petroleum and other equipment.