scope:

This NES covers the procedures and methods to be used for the Quality Assessment of Ultrasonic Examining Authorities and for production ultrasonic examination. The methods described are the minimum requirements for the detection of surface and sub-surface imperfections in welded and brazed joints, cast and wrought materials and for the measurement of plate and tube wall thickness, but does not contain acceptance criteria for defects thus revealed. Manual methods only are covered but automatic and mechanically assisted methods and associated recording systems are to be applied whenever the extent of the examination justifies the need to minimize operator induced variables and the equipment cost.

The effective application of ultrasonic examination may be restricted in materials with inherently high or variable attenuation or which produce severe scattering of the ultrasonic beam. Complex shapes may also limit satisfactory application and the examination is to be applied at stages during manufacture when the geometry of the component is relatively simple provided that subsequent specified treatments of the material do not render the examination ineffective.

The extent to which ultrasonic examination is required is not included herein. This will be stated in the Contract Documents.

This NES does not apply to nuclear plant and machinery to which DG Ships/PS/5108 applies.