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April 14, 2010

Types of Non-Destructive Testing

Filed under: Interesting — Tags: , , — Bradley Fraser @ 7:34 pm

The tensile-strength test is basically fruitless; at the time of the process of fostering data, the sample is destroyed. While this is not an issue when a decent store of the sample material is at hand, nondestructive techniques are better for materials that are expensive or complex to fabricate or that have been made into completed or semifinished samples.

Liquids

One commonly used nondestructive procedure, used to detect surface breaks and flaws in metal samples, uses a penetrating fluid, either luminescently dyed or fluorescent. After being smeared on the surface of the metal and set to fill into any surface flaws, the dye is cleared, leaving readily uncovered breaks and flaws. Another such method, better for nonmetals, takes an electrically charged liquid rubbed on the material surface. After superfluous fluid is removed, a dry powder of opposite charge is sprayed onto the sample and attracted to the cracks. Neither of these tests, however, can locate internal weak points.

Radiation

Internal, like external weaknesses, can be detected with X-ray or gamma-ray tests in which the radiation scans the object and impinges on a suitable photographic film. Under some circumstances, it may be possible to target the X rays to a particular part within the piece, creating a three-dimensional description of the flaw shape as well as its location.

Sound

Ultrasonic inspection of sections requires transmission of sound waves out of human hearing range through the material. In the reflection technique, a sound wave is targeted from one side of the sample, reflected by the other end, and returned into a receiver that is located at the starting part. When impinging on a flaw or crack in the test sample, the sound wave is reflected and its transmission altered. The actual delay becomes a measure of the location of the imperfection; a map of the test piece can then be created to show the location and form of the marks. By the through-transmission method, the transmitter and receiver are started at opposite areas of the subject; interruptions in the movement of sound waves are found to isolate and measure imperfections. More often than not a water medium is utilized in which transmitter, sample, and receiver are immersed.

Magnetism

As the magnetic aspects of a object are very much shown by its overall shape, magnetic methods can be utilized to demonstrate the situation and indicative dimensions of flaws and imperfections. By magnetic testing, an apparatus is employed that consists of a large coil of wire through which flows a steady alternating current (primary coil). Nested in this first object is a smaller coil (the secondary coil), to which is connected an electrical measuring tool. The steady current in the initial coil forces the current to react through the secondary coil by way of the method of induction. When an iron piece is placed within the secondary coil, sharp changes in the secondary current will implicate imperfections in the sample. This process only finds changes between sections in the length of a rod and will not detect long or continuous marks very much. A parallel technique, making use of eddy currents induced by a primary coil, also might be used to detect marks and breaks. A steady current is induced in part of the test sample. Cracks that exist across the transmission of the current make for resistance of the test material; this alteration should be measured under the correct items.

Infrared

Infrared methods have sometimes been utilized to locate material continuity in involved constructual objects. By testing the durability of adhesive joins in the sandwich core and facing sheets of a ordinary sandwich construction object like plywood, for example, heat is applied in the face of the sandwich skin object. When bond lines are continuous, those core samples show a heat sink within the surface object, and the general temperatures of the surface should spread lightly along those bond lines. In the case that a bond line may be insignificant, missing, or erroneous, however, temperature will not drop. Infrared photography of the area does demonstrate the placement and geometry of the broken adhesive. Another such method uses thermal coatings to change colour when reaching a devised temperature.

In conclusion, nondestructive techniques also are sometimes shown to reveal a total determination of the mechanical characteristics of a test sample. Ultrasonics and thermal processes appear the most promising in this area.

Looking for NDT Brisbane? For Brisbane non-destructive testing, contact Just Inspections today.

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December 21, 2008

Good Reasons to Pay Your Suppliers on Time

Filed under: Interesting — Tags: , , , , , , , , — Bradley Fraser @ 10:30 pm

Many small businesses spend far too much time on debt collection rather than their core business. Over the last 2-3 months I’ve noticed an increasing lag in payment cycles.

If you are in any sort of operation that uses small businesses as service providers or product suppliers it’s well worth your while to pay your bills on time and completely ignore to some “clever” accountants mantra of not paying until the second reminder. Guess what? People are human and they will pay back and pay forward. One way or the other you will pay in the end for screwing around your suppliers.

Here’s why:

1. If you pay on time you will get much better service. I know with my clients, the one’s who pay on time or early get the best service, day or night 365 days per year. These are A-Class clients. They pay on time or early, don’t bitch about the price, and as a result get excellent service and great value for money. They respect me, and I respect them. We both win.

2. If you don’t pay on time you reputation is on the line. Small business owners love to gossip. They slag off any customers who pay late. And with the Internet so freely available, your reputation can become crap overnight with one blog post. This leads into …

3. If you don’t pay on time, you can end up paying a premium. The current cost of money is about 1.5% per month. If your payment reputation is shite, than expect to pay at least 10-15 % more than if it were good or unknown. In some cases bad payers can be locked out of they supply chain completely and have to spend enormous amounts of time to find a new supplier.

With existing suppliers, if you screw them around, they will either add 10% to their next quote, or refer you to a lower-class competitor - hoping to send them broke because you don’t pay when due.

4. If you pay on time your staff don’t get harassed by debt collectors from your supplier’s accounts departments. This is a big source of staff burn-out. If you pay on time your staff won’t have to make up excuses for late payment and may actually start to enjoy their jobs.

In summary, if you want good service, good products, happier staff and ongoing loyalty, pay on time or before time and ignore your accountant’s advice.

What do you think? Why do you like early payment or not?

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Article supplied by Brisbane web designer and SEO Training.

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December 16, 2008

Laser Hair Removal Brisbane

Filed under: Interesting — Tags: , , , — Bradley Fraser @ 6:44 pm

 

 

Brisbane Laser Hair Removal

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