In order to explore the flow characteristics of vertical pipe in the deep⁃sea horizontal pipe⁃catenary system, in this paper, aiming at an oil and gas field in the south China sea, the influence of diameters, total flow rate, water cut and outlet pressure were simulated. The results show that the position of the flow state in the pipe is the boundary, and the influence of each influencing factor on the flow state parameters in the pipe shows different changes, but the temperature distribution along the pipe is not affected by the relevant factors; From the perspective of the research scope of the above four parameters, the influence process of each parameter is divided into different stages. The influence of pipe diameter is divided into two stages: D=0.06~0.12 m and D=0.12~0.50 m, the total flow of Q=0.001~0.030 m3/s and Q=0.100~0.300 m3/s, the water content of w=10%~25% and w=25%~30%, and the outlet pressure is divided into three stages, including 0~5.0, 5.0~7.0, 7.0~10.0 MPa.

The corrosion damage mechanism of heat exchanger in visbreaking unit was studied, through field morphology observation, scanning electron microscopy (SEM) micromorphology, energy spectrum analysis (EDS) and corrosion coupon experiments, and find out the naphthenic acid corrosion damage reason of the exchange tube heat exchanger and baffle plate, further analyzes the naphthenic acid corrosion mechanism of carbon steel; Then through a variety of material corrosion coupon experimental comparison, the anti⁃corrosion measures are put forward. The research results show that the corrosion of heat exchanger leakage and crude oil viscosity device, high acid value, the water content of the working temperature of heat exchanger and the material, dehydration of crude oil and reasonable change of the working temperature and material of the heat exchanger can effectively reduce the corrosion damage of the heat exchanger of the viscosity reducing device.