公开(公告)号：US20240383076A1

公开(公告)日：2024-11-21

申请号：US18199371

申请日：2023-05-19

Applicant: Tianjin University

Inventor： Yongdian HAN ,  Jiyuan FEI ,  Lianyong XU ,  Lei ZHAO ,  Kangda HAO ,  Hongyang JIN

IPC: B23K31/12 ,  G01N3/08 ,  G01N33/207

Abstract: A method for determining the filling welding parameters of large deformation pipeline steel based on secondary regulation method includes: welding specimens to be welded for secondary welding thermal simulation experiments based on a thermal simulation to obtain samples after thermal simulation; processing the samples after thermal simulation into CTOD samples and calculating fracture toughness parameters; pre-loading of specimens requiring pre-strain after thermal simulation by uniaxial tension, and then processing samples before and after pre-strain after thermal simulation, conducting slow strain rate tension tests and calculating stress corrosion cracking susceptibility parameters; comparing the change in elongation of the samples before and after pre-strain and calculating the pre-strain sensitivity parameters; determining secondary thermal simulation parameters; converting the secondary thermal simulation parameters into welding heat input parameters; determining welding parameters based on welding heat input parameters; determining the optimal role of the welding parameters.

公开(公告)号：US20230228728A1

公开(公告)日：2023-07-20

申请号：US17954682

申请日：2022-09-28

Applicant: Tianjin University

Inventor： Yongdian HAN ,  Shifang ZHONG ,  Lianyong XU ,  Hongyang JING ,  Lei ZHAO ,  Kangda HAO

IPC: G01N33/207 ,  G01N30/62 ,  G01N33/2045 ,  B23K31/12

CPC classification number: G01N33/207 ,  G01N30/62 ,  G01N33/2045 ,  B23K31/125 ,  G01N2030/027

Abstract: The present invention discloses a quantitative evaluation method for sensitivity of welding transverse cold cracks in a typical joint of a jacket, including following steps: S1, performing macroscopic analysis, metallographic analysis, fracture analysis and hardness analysis on cracks of a failed component to obtain main causes of cold crack failure; and S2, designing and processing a dedicated sample, and performing rigid restraint crack tests on the dedicated sample at different preheating temperatures to obtain a cracking/non-cracking critical restraint stress σ1cr of the sample. According to the method, a rigid restraint crack test is applied to evaluation of sensitivity of welding transverse cracks, so that external restraint conditions borne by a welding joint can be accurately simulated, a stress state of the welding joint in an actual working condition can be truly reflected, the overall evaluation precision is greatly improved, and a foundation is laid for accurately evaluating sensitivity of welding cold cracks in a tube joint. Furthermore, a welding technology (base material, welding material, welding process and restraint level) is designed to restrain cold cracks from cracking, and the method has important theoretical significance and engineering value.

公开(公告)号：US20240012958A1

公开(公告)日：2024-01-11

申请号：US17979002

申请日：2022-11-02

Applicant: TIANJIN UNIVERSITY

Inventor： Lei ZHAO ,  Molin SU ,  Yongdian HAN ,  Lianyong XU ,  Kangda HAO

IPC: G06F30/20 ,  G01N33/2045

CPC classification number: G06F30/20 ,  G01N33/2045 ,  G06F2111/10

Abstract: A method for characterizing propagation of metallic short cracks and long cracks includes: acquiring crack tip opening displacement in a metallic notched sample under cyclic loading; acquiring crack tip opening displacement amount caused by a single monotonic tensile in the notched sample, and crack tip opening displacement caused by monotonic tensile in the notched sample under a maximum far-field stress; and based on an original Shyam model, constructing, according to the crack tip opening displacement amount and the crack tip opening displacement by obtaining yield strength of metals, a Tmφc model for characterizing the propagation of short cracks and long cracks, where the Tmφc model is used for representing the growth rate of short cracks and long cracks.