Abstract: During the development of oilfield, through specialized in thermal recovery well high temperature steam is injected into the reservoir, so that the heavy oil can be mined, thereby improving the recovery efficiency of oil reservoir. Thermal recovery casing head is one of the ground equipments for heavy oil thermal recovery, which is installed in the casing above the surface. RTGT13-3/8 ×7-35 casing head is the product designed and produced based on the need from oilfield user, mainly used for fixing wellhead of drilling wells connecting downhole casings, and reliably sealing and controlling the annular space, so it is an important part of the casing head. Compared to ordinary thermal recovery casing heads, it is improved both in material selection and structure, and can fully meet the requirement of subcritical steam injection techniques.