With the development of industrial production and the improvement of people's living standards in the world, the demands for natural gas are increasing so higher and more stable production requirements are put forward for natural gas wells. The downhole throttling technology is introduced to the production process of natural gas wells to reduce wellhead pressure and prevent hydrate formation. The core equipment of downhole throttling technology is a restrictor which is divided into two types: preset type and rear type. The preset restrictor plays an extremely important role in the development and production of new gas wells. In this paper, firstly, a more reliable and safer preset gas nozzle retrievable restrictor is designed according to the user's needs and its working principle is expounded. Secondly, two key process parameters of the throttle: the minimum setting depth and the inner diameter of the gas nozzle are designed and calculated, and the influence of these two parameters on daily gas production are analyzed by PIPESIM software. Finally, the production design is carried out from the production data of a gas well, and then the wellbore pressure, wellbore temperature and hydrate formation temperature distribution map are analyzed to determine the optimum setting depth. The analysis results shows that the problems of high wellhead pressure and hydrate formation in the wellbore can be effectively overcome by using the downhole throttling technology. Moreover, the stable production of gas wells can be ensured and the development cost can be reduced by selecting the appropriate key process parameters.