Unique Transmission Equipment (Luoyang) Co., Ltd. has designed a type of high precision internal gear spur gear slewing drive for customers, which is used on light-duty automation equipment. Compared with external gear spur gear slewing drive, the internal gear slewing drive saves more installation space and also improves torque accordingly. The teeth of the slewing drive were quenched and then ground. The slewing bearing adopted 0 clearance design to make rotation more flexible. Finally, the runout of the installation surface was ≤ 0.03mm. In order to fit customers’ gearboxes, we have specially designed the adapter flanges. In the end, rigorous technical requirements and strict quality control make the finished slewing drives to have the advantages of high precision, small size, smooth operation and long service life, and meet the customers’ usage needs.