There are two industries that require tig welding certification.

1. Industrial piping, (including boiler tubes)
2. Aerospace and aviation (manufacture and overhaul/repair)

For tig welding certification in piping, pressure vessels, and boilers, ASME section IX of the "Boiler and Pressure Vessel Code" specifies the criteria for acceptable welding tests.

For Aerospace tig welding, the American Welding Society (AWS) D17.1 - "Specification for Fusion welding for Aerospace Applications" is the code for welding certification tests.

More often than not, a 6G position welding test is required to certify for Pipe welding jobs. On many boiler jobs, 2" heavy wall tubing is tig welded all the way out in the 6G position making the welder either switch hands, or at least get in some uncomfortable positions. That is why 6G position Tig welding tests are considered the most difficult.

Most of the time, sheet metal test pieces in the 0.020"-0.125" thickness range are used for aerospace welder qualification testing. The 6G welding test is only used occasionally because it does not accurately represent the scope of welding tasks performed for most aerospace and aviation welding applications. AWS D17.1 even has a provision for welders to certify on a scrap part or mock up of a weld that is not represented well by a plain groove or fillet weld.

ASME section IX Boiler and Pressure Vessel Code has been around for a very long time, but AWS D17.1 is relatively new and was written to replace 2 old Mil standards... 1595a and 2219.

One thing both welding certification specifications have in common is that the test welds that are selected to be used for certification tests only qualify the welder for a range of positions, thicknesses, and joint types. No single test qualifies for all the possible material, thickness, positions, and joint types that are possible. That is why some welders hold a dozen or more certifications.

One main difference in welding tests for these 2 industries is that the initial welding test for Pipe welding jobs are largely done using low carbon steel or stainless steel. Other materials like inconel are sometimes used also but not nearly as much as carbon steel and stainless.

In the Aerospace and aviation industries, It is not uncommon for a welder to be tested on carbon or low alloy steels, stainless steels, nickel alloys, aluminum, magnesium, titanium, cobalt alloys, and even some refractory alloys like Niobium...with separate welding tests required for each material category.

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As with most machinery you do not necessarily need a license to operate a powered pallet truck as the company who are requiring you to use the pallet truck will provide the necessary training. If the company fails to offer such training then you are at risk of hurting yourself or another person in which the company is liable. Although it is not required some companies with their training of powered pallet trucks give certificates to show competence of the machine, whereas other companies usually smaller companies do not give out certificates and only provide the training.

So what kind of training do you need to operate a powered pallet truck?

If you are working in a job where using a powered pallet truck is necessary you will receive training. A general training regime may look a little like this:

• An Introduction
• Theory and Video
• Operators Safety Code
• Responsibility under the HSE act 1974
• Battery Charging
• Truck Stability
• Motive and Hydraulic Controls
• Pre-shift checks recording

Once the candidate has gone through the proper training a few tests will be performed that the candidate will be required to pass. In the event that the candidate fails the tests, he or she will need to sit through the training again and re-take the tests.

The candidate will be required to pass:

• A theoretical test
• Pre-use checks
• A practical test

Always remember to never operate a powered pallet truck, or any type of machinery, without the proper training as this can result in injury and accidents which you personally could be held responsible for.

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The previous article in our Roush F-150 project truck series covered the Roushcharger intercooled supercharger installation article. Before and after power gains were left out and I'm sure many of you are dying to know the bottom line results. We did a series of dyno pulls before and after the supercharger installation in order to get a picture of the power gains. Graphs alone don't tell all the data unless I present some additional information with each graph.

You'll notice the graphs do not start at idle speeds. When you go from idle to full throttle on these trucks there is a sudden shock of power through the torque converter. With manual trannies you'll generally see numbers generated lower in the RPM range. The more power from the start, the higher the RPMs before the dyno's drum sampling settles enough to get good numbers. This power surge is even more apparent with the supercharger.

In the above graph you see stock horsepower and torque. There are a couple of things to note here, or the Roushcharger graphs persented later won't make sense. First, you'll see that this chart plots the truck's power all the way to 5800 rpm. This will not happen in real life driving. The 5.4L 3-valve V8 has shift points around 4800-4900 RPM so the graph in real-world usage would suddenly drop around 4900 rpm. Second, the abrupt drop-off at 5800 RPM is due to the factory RPM rev limiter.

In this chart you see the Roushcharger horsepower and torque. Again, there are a few things of interest here that help make sense of the plot lines. First, you'll see horsepower and torque drop off quickly at about 5400 RPM but it doesn't on the stop graph. This doesn't mean there is a power loss here. What is happening is the computer is kicking in the boost-dump to prevent over-boosting the engine. This happens at (according to the raw data from the dyno) exactly 5316 RPM. This does not impact the truck at all in real-world conditions with the standard Roush tune because the shift occurs at 4900 RPM, well before the boost-dump kicks in.
Here you see the graphs overlayed. The total power increase was 121.26 HP and 118.22 ft/lbs. torque. Based on the graph trends it looks like peak torque with the Roushcharger is actually much higher in the lower RPM ranges than this chart reveals (this truck will launch hard from a standstill). These numbers, for "at the wheel numbers" are impressive and well within Roush specs when you consider drive-line loses on a 4x4 truck with 20 inch wheels. The torque peaks very early meaning the truck starts up quick, and stay nearly flat across the entire rpm range, with horse-power increasing throughout the chart. What does this all mean? Basically, not only does the truck come off the line fast but it keeps gain speed very quickly without falling off in power like you'll typically see in natually aspirated engines. Unlike a Mustang GT, which takes time to get into its peak torque area, a Roushcharger equipped F150 is almost at peak torque right off the line. With proper launching for traction, most Mustangs don't stand a chance even against the much heavier F150.

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