Principles of the Design Phase
Principles to be followed
mechanical stability principle, material adaptation principle, environmental adaptation principle
Load analysis: Calculate permanent load (self-weight), variable load (fluid pressure, wind load) and accidental load (earthquake).
Material selection: carbon steel, stainless steel or composite material (material selection should be based on environmental corrosiveness and temperature)
Software assistance: Perform finite element analysis (FEA) (apply ANSYS or AutoPipe) to optimize pipeline stress distribution and deformation control.
Calculation and configuration of the support system
The support structure is the most critical in ensuring the safe and convenient operation of the pipeline. There are several key points to pay attention to:
Type selection: fixed brackets that limit displacement, sliding brackets that allow thermal expansion, and spring supports for dynamic shock absorption.
Mechanical calculation: The reaction force, bending moment, and shear force of the support point should be calculated repeatedly to ensure that the force during application is lower than the yield strength of the material.
Spacing optimization: According to the ASME B31.3 standard
Horizontal pipeline support spacing formula
(EE is the elastic modulus, II is the moment of inertia, and ww is the uniformly distributed load)
Technical points in the construction (Build) phase
The following practices should be implemented in combination with the design and support solutions:
Prefabrication and welding: To ensure that welds that meet the API 1104 standard are generated and the pass rate of non-destructive testing (UT/RT) is greater than 99%. Fully automated welding robots should be used,
Support installation: The embedded depth of the anchor point must be ≥ 1.5 times the diameter of the pipeline, and the bolt torque value is calibrated according to GB/T 3098.1.
Acceptance test: 1.5 times the working pressure for 30 minutes, laser centering detection deviation <2mm/m
Comprehensive case analysis
Project background: A LNG gas pipeline project in 2025 (length 120km, DN800).
Design: Duplex stainless steel 2205 is used to resist H₂S corrosion;
Support: Sliding brackets are placed at every 15m interval, and hydraulic dampers are installed at each elbow;
Construction: Modular prefabrication reduces the on-site construction period by 20%, and the BIM model guides the installation simultaneously.
Whether the design of the structured pipeline is reasonable, whether the support is accurate, and whether the construction is standardized directly affect the life of the structured pipeline. In 2025, the penetration rate of AI algorithms in the industry has reached 65%. With the addition of digital twins, the management of the entire life cycle will greatly improve safety and economy.
