Nondestructive Testing

TMG provides nondestructive testing (NDT) under ASNT SNT-TC-1A — Personnel Qualification and Certification in Nondestructive Testing, with ASNT Level III oversight on ultrasonic (UT) and magnetic particle (MT) testing. Liquid penetrant (PT) and visual (VT) testing round out the surface-method scope. NDT is offered as a standalone service and as a method within a broader welding or structural special-inspection scope.

TMG's role on an NDT engagement is observation and reporting. Authority to accept or reject work rests with the owner or the owner's designated representative.

Ultrasonic testing (UT)

UT detects surface and sub-surface discontinuities in metals, weldments, plate, and rolled shapes using high-frequency sound coupled into the material and reflected from boundaries within it. TMG performs three UT configurations:

• Ultrasonic thickness testing (UTT) — pulse-echo measurement of remaining wall thickness on tanks, vessels, piping, and structural elements, for corrosion and erosion tracking and baseline records.
• Shear-wave (angled-beam) UT — the primary method for complete-joint-penetration (CJP) groove welds. Detects fusion-type discontinuities, planar flaws, and cracks not visible at the surface. Evaluated against AWS D1.1 — Structural Welding Code – Steel, Section 8 (or the equivalent clause in the controlling code).
• Longitudinal (straight-beam) UT — plate, bars, castings, and laminations; detects delamination, internal porosity, and planar flaws perpendicular to the beam.

Magnetic particle testing (MT)

MT detects surface and near-surface discontinuities in ferromagnetic materials. A magnetic field is induced into the part; iron particles — applied dry or in a wet carrier — collect at the flux leakage produced by a discontinuity, making the indication visible. MT is the routine surface method for fillet welds, weld toes, and machined parts. TMG performs wet and dry MT with active and residual magnetization techniques as the written procedure requires.

Liquid penetrant testing (PT)

PT detects discontinuities open to the surface in both ferromagnetic and non-ferromagnetic materials — including austenitic stainless and aluminum. Visible or fluorescent penetrant is applied to the cleaned surface, the excess removed, and a developer draws penetrant out of any surface-breaking flaw to make the indication visible.

Visual testing (VT)

VT is the foundational NDT method — direct examination of welds, fasteners, structural members, and coatings, supplemented by gauges, mirrors, borescopes, and video-borescopes for confined-access work. VT is performed against documented acceptance criteria from the controlling code and underpins the visual welding-inspection scope on the Welding Consulting page.

ASNT Level III consulting

Beyond field testing, TMG provides ASNT Level III consulting: development of an organization's written practice, NDT procedure development, and program audits — serving as the responsible Level III where retained.

Specialty applications

• High-strength bolt pre-installation verification — Skidmore-Wilhelm bolt-tension calibrator testing per the RCSC Specification for Structural Joints Using High-Strength Bolts.
• Aboveground storage tanks — UT thickness mapping with VT and MT or PT on seams and appurtenances per API 653 (and API 650 for new construction).
• Post-installed concrete anchors — pull-out and proof-load verification per the manufacturer's evaluation report and ACI 318, Chapter 17.
• Amusement rides — structural and weld NDT of ride structures and components.
• Hardness testing — portable hardness measurement for heat-affected zone and post-weld heat-treatment verification.

Engagement

ASNT Level III consulting — written-practice development, procedure development, and program audits — is available on a retainer or ongoing-program basis. Field NDT is priced by day rate, per-visit call-out fee, or Time-and-Materials. Written procedures are developed project-specifically and reviewed against the controlling acceptance criteria before mobilization; procedures, calibration records, and Level III qualifications are shared with the client at engagement. TMG serves Florida and the Southeast. See welding consulting and UAV services, or the contact page to request a proposal.