steel structure damage detection

Guangzhou Steel News: steel structure damage detection

Construction project cost structure and determine

Guangzhou Steel knowledge: steel structure damage detection

1. The type of injury: force, temperature.

2. Test content: (1) member flatness; (2) surface defects member; (3) the connection (welding, bolting); (4) steel corrosion; (5) Fire coating thickness.

Content method
Member flatness beams and trusses: a plane perpendicular plane deformation and deformation of lateral deformation pillars: pillar inclined deflection. Tension between the fulcrum member a thin wire, measured sag and skewness of each point.
Tilt column theodolite; deflection of the column with a hammer hanging wire measurement.
Slenderness ratio of member local flatness of crack damage detection member: Check the available visual method, hammering method is mainly used to check that bag with a rubber mallet to gently tap the various parts member. 10x magnification can also be checked one by one. Suspected crack, drip method available. When no crack, an arc-shaped oil diffusion; when the cracks, will go into the oil. You can also use ultrasonic flaw detector inspection.
Visual surface defects or 10x magnification. Vortex, magnetic, and other nondestructive testing penetration.
Welding cracks, pores, slag, lack of fusion, Weld, undercut, craters and other defects. With 10 times the magnifying glass, small hammer, ultrasonic flaw detector, ray detector checks.
Ultrasonic thickness and corrosion of steel vernier caliper.
Fire coating thickness gauge.

[Extensions] Eddy current testing is the conductor close through AC coil, eddy currents in the conductor establishment. Conductor eddy current will generate its own magnetic field, the magnetic field changes the role of the original vortex magnetic field strength, and thus lead to changes in voltage and impedance of the coil. When the conductor surface or near-surface defects, will affect the intensity and distribution of the eddy current, and eddy current change causes a change in voltage and impedance of the detection coil, according to this change, it can indirectly lead to know the existence of defects in the body.

Magnetic particle inspection utilizing magnetic interaction between magnetic fields and leakage defect at the workpiece, it utilizes steel products surface and near surface defects and differences in permeability steel permeability, the magnetic field after magnetization of these materials will occur at the discontinuities of distortion, magnetic flux leakage at the surface portion is formed to produce a leakage magnetic field to attract magnetic powder forming defect accumulation - magnetic marks, under appropriate lighting conditions, showing the position and shape of the defect, to observe and to explain the accumulation of these magnetic powders , to achieve a magnetic particle inspection.