Small Nozzle Weld Inspection

2025-05-23 17:38 YTZX

Small Nozzle Weld Inspection

Detection Principle

Based on the electromagnetic induction principle, when alternating current is supplied to the excitation coils of the flexible array eddy current probe, an alternating magnetic field will be generated near the inspected small nozzle body and weld, inducing eddy currents within the metal material of the nozzle.

If cracks appear on the surface or subsurface of the nozzle body or weld, the high resistance at crack areas will distort the propagation path of eddy currents, making the currents deflect towards crack edges and bottoms, which further changes the distribution of the induced magnetic field around the nozzle.

Multiple induction coils inside the flexible array eddy current probe can capture these magnetic field variations and convert them into electrical signals. Subsequent analysis and processing of the signals enables judgment on crack existence, as well as the position, shape and other characteristics of defects.

Application Advantages

High Sensitivity and Resolution:

It can detect extremely tiny cracks in small nozzle bodies and welds, and effectively identify cracks with shallow depth and narrow width. It can accurately distinguish multiple closely adjacent cracks, avoiding missed detection and misjudgment.

Non-contact Inspection：No grinding of surface coating on small nozzles is required, which prevents surface damage to the workpiece. Complicated surface cleaning and grinding procedures can also be omitted.

It is highly applicable to the inspection of small nozzles with anti-corrosion coatings, capable of significantly boosting inspection efficiency and cutting testing costs.

Adaptable to Complex Shapes and Structures：The flexible probe can bend and deform according to the shape and size of small nozzles, achieving close fitting on the component surface. It enables all-round and dead-angle-free inspection for small nozzles of various forms such as straight sections, elbows and tees, as well as complex weld structures, guaranteeing comprehensive and accurate detection results.

Rapid Scanning and Imaging：

It supports rapid large-area scanning inspection and can finish the detection of small nozzle bodies and welds within a short period.

Meanwhile, equipped with advanced signal processing and imaging technology, it displays detected crack information in intuitive images, helping inspectors quickly and accurately determine the position and morphology of cracks.

Multi-parameter Detection：Besides crack detection, it can simultaneously acquire variations of other parameters of small nozzles, including electrical conductivity and magnetic permeability. Comprehensive analysis of these multi-parameter data enables full evaluation of material performance and defect status, providing sufficient data support for subsequent repair and maintenance work.

Test Procedure：

Test Block：Small Nozzle Butt Weld Test Block

Description：small nozzle weld、weld heat affected zone (HAZ)、body crack

As follows:

Small nozzle weld crack