By Ana HendersonAugust 12, 2019
Yuma Test Center's motto is "Truth in Testing" and that is Subject Matter Expert Lead of Non-Destructive Testing, Mechanical Engineer, David Le's mission with non-destructive inspections at the Yuma Proving Grounds (YPG) Metrology and Simulation Division.
Le says as a test center, "We have to perform the inspection and measurements at a higher precision level requirement, than private industry" adding, "A lot of the weapons systems coming here to YPG for testing are looking to optimize the design and performance. Our inspection findings, the data, and the photographs, give valuable information to evaluators, engineers and designers, to optimize what they are testing."
Weapon technology is continually advancing and the inspection equipment must keep up with it in order to help push the boundaries of future weapon capabilities. The latest piece of inspection technology acquired by Metrology Branch helps uphold this standard.
In April, YPG purchased a high-tech cannon tube inspection system which can detect very small cracks that may occur during testing, and can also see propellant residue in the interior bore surface of a tube to evaluate the cannon tube cleaning procedures. The system is called the High-definition Ultraviolet Visual Borescope inspection system and is used for visual borescope inspection and the magnetic particle inspection of the cannon gun barrel. It has the capability to inspection 105, 120 and 155mm cannon tubes.
Until recently, the inspection team, used two individual analog tube inserts, one with an ultraviolent light attached and one with a white light for inspections. To capture photographs of the interior of the cannon tube the team would have to place a digital camera at the end of the 20-foot tube to capture the images of the cracks and wear. This method was considered high tech at one time, but it was time to use a method with the amazing optical clarity being offered in 2019.
With the new system, all the accessories are built into one. The high-definition video camera system goes into the cannon tube, then using the mouse and computer monitor an inspector can adjust the focus and lighting of the camera to see very fine details.
The team has a real-time view of the interior of the cannon tube on a 40-inch computer monitor, and with a click of a computer mouse they can capture high-definition photographs or video.
"We have the high-definition video camera and an images transfers from the camera directly into the high-definition monitor. We are able to view, capture and store the images and make video. "
The previous ultraviolet light intensity was 1,200 megawatt per centimeter square. The new system has 6,000 megawatt per centimeter, five-times the light intensity, Le explains "It's capable to make adjustments, from low to medium and medium to high intensity which allows us to see the surface better and for the camera to focus on the surface to detect cracks."
The white light provides increased intensity that provides high-definition images which allow inspectors to zoom into an image approximately 15 times without losing visual resolution. The white light inspection detects debris or lint that might have entered the bore surface via the cleaning cloth or brush.
In the past, the ultraviolet and white lights were used separately, now both lights can be used simultaneous which Le says "Makes the process of the inspection go faster and more accurate. We are talking about speed and accuracy."
The still image resolution goes from 1200 megabyte to 1800 megabyte, "It's really high-definition and we are able to see more details" says Le.
Adding, "We can actually see really well with the crack indentation about 5,000 of an inch width and 10,000th of an inch long easily."
To put that in perspective, the size of the human hair is about 3-4,000th of an inch thick diameter.
The system software shows the position and location (angle and axis) of the camera (when inside the cannon tube) on the screen, allowing inspectors to pin point exactly where cracks are located. "If we see any type of feature show up on the screen, we are able to see the location."
This technology helps set a baseline for any existing wear, inspectors can measure if the cracks changed after testing and also capture new cannon tube wear.
The system also allows them to make annotations on the images.
These clear images and accurate measurements essentially eliminate the need to repeat processes like in the past, "It would take four to six hours looking in the cannon tube, with the new system, it's one shot going into the barrel and we are able to see on the image on the screen with one touch and record the entire cannon tube."
Applying new technology that is built into the system provides customers with the most accurate information on the condition of their test item.
With research development testing at YPG, if a weapon has an issue while testing, the test team brings the cannon tube into the inspection shop for crack detection, evaluation of erosion or dimensional laser bore mapping.
"Sometimes they see a cannon four times in week or two times in a day."
Regardless, inspectors need to provide answers in a timely manner to keep the test moving forward.
"We have the equipment capability to handle this type of testing requirement from the customer, so they can turn around and get back on the testing schedule."