S.W.I.S.
Set In (Nozzle) Weld Inspection System

Many of the more experienced in the practice of ultrasonic inspection appreciate the difficulties associated with the inspection of nozzle saddle welds. The Saddle Weld Inspection System (SWIS) simulates the manual operators dexterity in rotating the probe whilst scanning around a nozzle.

In S.W.I.S these movements are motorised and encoded so that, with suitable software, defects in different orientations can be shown plotted within the weld profile.

Benefits

• Flexibility - covers a number of nozzle to pipe sizes for example 4, 6, 8 and 10 inch branches for thirty six inch main pipe (other nozzle to pipe combinations can be accommodated.
• High positional accuracy.
• Probe skew to set pattern to correct for geometric skewing of beam.
• D.C servo actuators to reduce electric interference with Ultrasonic trace.
• Quadrature optical encoders to match to Programmable Motion Controller.
• Operates in any orientation.
• Fabricated from durable materials for reliability and longevity.
• Constant force tensator probe springing allowing an 80mm rise and fall of probe.

Construction and Use

The Phoenix Saddle Weld Inspection System is a scanning mechanism for the ultrasonic inspection of nozzle welds from the external surface. Intended for use with the larger nozzle diameters found in Nuclear Reactor coolant loops of a pressurised water reactor it has been designed to operate in any orientation. To ensure reliability and longevity only durable materials such as stainless steel, hard chromed steel, and anodised aluminium are used throughout. The manipulator uses a fixed ring for location to achieve high positional accuracy.

The manipulator is divided into four major components:

• The fixed ring with its associated mounting.
• The carriage assembly and primary motor drive system to move the radial arm around the nozzle.
• The radial arm assembly with its associated drive causing the probe, in its Toolpost, to scan towards and away from the nozzle.
• The Skewing Head, mounted to the Toolpost, to provide rotation of the probe about its axis.

The radial arm is pivoted to accommodate the saddle geometry and is loaded onto the nozzle surface by a gas spring. The probe carriage is driven along the radial arm on a ground vee slide using a zero backlash belt drive. A DC servo actuator is an integral part of the radial arm and includes a Harmonic drive gear box, to further reduce backlash. Positional feedback is provided by an incremental encoder.

The probe carriage runs off vee journals, including a Toolpost which allows an 80mm rise and fall of the probe. The Toolpost is spring loaded and incorporates a low friction slide and constant force springs.

User Support

Phoenix Inspection Systems is responsible for the design, manufacture and supply of all its equipment. Comprehensive customer support and training is available as a matter of course. In addition, a specialised consultancy service, based on extensive practical experience of N.D.E systems, can be called upon to advise on specific inspection problems.