Magnetic Particle Testing
This NDT method is used for detection of surface and near-to -surface discontinuities in ferromagnetic materials, by applying a magnetic field and a medium sensitive to areas of magnetic flux leakage. The medium will be attracted, and held, to the part surface (by flux leakage) and the visual indication of a discontinuity then interpreted by a qualified operator.
Advantages of magnetic particle inspection include:
- best method for the detection of fine, shallow surface cracks
in ferromagnetic materials
- will work through thin coatings of paint
- few limitations regarding the size or shape of test specimen
- highly portable NDT method
Liquid Penetrant Testing
The penetrant, when applied to the clean surface of a test part, will "work" its way into the surface opening by capillary action. After a suitable length of time has been allowed for this action, the excess penetrant is removed from the part surface . The penetrant in a surface opening will then "bleed" back to the surface (often aided by use of a "developer") and form a visible indication on the part surface.
Advantages of liquid penetrant inspection include:
- highly portable NDT method
- highly sensitive to fine, tight discontinuities (up to 4 micro-in)
- can be used on variety of materials
- all surface discontinuities are detected in one operation,
regardless of orientation
Ultrasonic Testing
This NDT method employs high frequency sound
in the range of 0.2 MHz to 25 MHz to detect internal
discontinuities in the part under test. Ultrasonics is
based on the principle that a change in acoustic
impedance (the resistance of a given medium to the
passage of sound) in a material will cause a
reflection of some or all of the incident sound beam
(much like an echo). High frequency sound is
transmitted into the material by a piezoelectric
crystal which has the ability to change electrical
energy to mechanical energy and vice versa. The
“echoes” received are converted to electrical signals
which are displayed on a cathode ray tube.
Advantages of ultrasonic inspection include:
- Access to only one side necessary
- Can be used on a variety of materials
- Best method for detection of internal, planar
discontinuities
- High penetration capabilities
Visual Inspection
Visual inspection is the one NDT (Non Destructive Testing) method used extensively to evaluate the condition or quality of an item. It is easily carried out, inexpensive and usually doesn't require special equipment.
In Shop and On Site Services
One of the advantages of Nondestructive Testing is
that many of the methods are extremely portable and
tests can be carried out on our customer’s premises.
Our Sorting, Inspection, Rework and Containment
services (GP-12) can be completed in our facility or
at our customer’s.
Inspections are performed in accordance to specifications such as ASTM, ASME, Military Standards and Customer
Specifications and Procedures.
