Papers by Author: Chun Li Mo

Abstract: In this paper temperature field of multi-coil during batch annealing process in strong forced convective hydrogen atmosphere of Bell-type furnace was simulated, and the influences of heat transferring between steel coil and air flow under a given condition on the temperature field of the steel coil were studied. And then, the temperature field of a single and three coils steel plate were calculated during reheating, holding and cooling process according to the measured annealing curves. The simulated results show that the same trend of temperature in different steel coils. However, considering the heat radiation of steel coil, temperature variation in the topside of coil is higher than that in the bottom of coil.

Abstract: Fully-welded ball valves are widely used in the crude oil/natural gas transmission pipelines, and their quality has a direct bearing on the transportation safety of national energy. Two paralleled and symmetrical circular welds are used in the main welds of valve body, and the narrow-gap submerged arc welding (NG/SAW) is used in the welding groove. Because of conditional restrictions, it is impossible for the value to be post-weld heat treatment (PWHT). Therefore, the welds must have high impact toughness and strength. In order to study the welding performance of the base metal, SAW is used in the welding of proving rings of steel LF2 fully-welded ball valves. CTOD tests are applied to welding joints, and the result suggests that the minimum CTOD value of the valve’s welds and heat affected zone (HAZ) is more than 0.15mm. According to the criterion DNV-OS-C401, the welds in the fully-welded ball valve are safe enough without PWHT.

Abstract: Body Heat Flux Mode characterised by Element Birth and Death method is built to simulate the thermal effect of target GH3536 irradiated by HIPIB with different energy parameters using the FEM (Finite Element Method) software. The thermal data of the metal surface irradiated by HIPIB is obtained. The simulated result has proved that the explosive eruption of the inner surface is the dominant mechanism of the formation of dense craters with large sizes when the ion current energy input is high.