Steam yarn is also called add nib, in the production of hot steam to wool yarn and wool blended yarn setting process. In the process of wool spinning, the internal stress is out of balance due to repeated force and friction, which leads to deformation, fatigue and static electricity. Wool yarn has a great untwist torque, which will affect the process of back-end production. Using the heat and moisture condition to stabilize the yarn twist can prevent the yarn from twisting and winding when the fiber is loose, and avoid the defects of fabric such as weft shrinkage. With the development of textile industry, steaming technology has been used in cotton, hemp, chemical fiber and other fields. The steaming process improves the overall performance and quality of the fabric, makes the fabric more stable in size, soft and plump in hand, improves the production efficiency and shortens the delivery time, for the enterprise in the fierce competition to increase the advantage.