Abstract: Firstly this paper introduces the classification of dry gas seals in API 692. Taking the most commonly used series seal with interstage labyrinth seal as an example, it lists the system configuration schemes of dry gas seal in detail. API 692 divides the dry gas seal system into 6 parts and 38 subcategories. Under different circumstances, different subcategories are selected to form the dry gas seal system. Then, the differences between engineering design and specification requirements are compared with examples according to the authors' understanding. API 692, as a newly issued standard, provides a detailed basis for the design and manufacture of dry gas seals. At present, many projects have not fully implemented API 692 standard. In the future, if this standard is strictly implemented, all parties need to study it in detail and gradually adapt to it.which has achieved many successful applications in engineering practice. In this article, several solutions of naphtha hydrotreating feed heat exchanger have been analysed and compared. The optimization of solutions and recent application of heat transfer enhancement techniques have also been summarized.

Key words: API 692, dry gas seal, configuration of dry gas seal system