LTI and Peak Beam Make the World Safer
Peak Beam Systems Inc. of Bala Cynwyd, PA manufactures high intensity
lighting products that illuminate targets up to 1.5 miles away. The
lighting systems are used by the military, government, law enforcement,
fire fighters and the entertainment industry. These searchlights need
to hold up under heavy usage, so Peak Beam president, Bill McManus,
came to LTI to test their durability. He also wanted to determine the
structural integrity of certain parts, assemblies and adhesives.
Testing was performed under normal and extreme conditions to determine
the failure point. The testing results provided information to establish
the safety margins between the normal working load and the failure of
the part. Manufacturing process parameters were also determined to provide
a consistent product part.
The lighting system that was tested consisted of a light attached to a battery with a typical coiled cord. It was determined that the weight of the system is 8.6 pounds. When in use, it is often carried by a shoulder strap attached to lifting ears.
When the complete searchlight assembly is carried by the shoulder strap, the integrity of the lifting ears comes into question. Additional force might be generated if the person carrying the assembly was running over rough terrain. This action might exert momentary forces up to two times the normal weight loading (17 lbs. 2 ozs.), resulting in bouncing and additional pressure on the lifting ears.
To simulate these conditions, a pull type test was performed utilizing a
tensile test machine. Three finished batteries were chosen at random for
testing. Two separate pull tests were performed on each battery by exerting
pressure on one pair of diagonal corner ears during each test. Increasing
pressure was applied until one of the parts failed.
Testing was performed under normal and extreme conditions to determine
the failure point. The testing results provided information to establish
the safety margins between the normal working load and the failure of
the part. Manufacturing process parameters were also determined to provide
a consistent product part.
The series of tests provided information on the amount of pressure that the ears can withstand before distortion and failure occur. During all of the tests, there were no signs of distortion until the pressure reached at least four times the normal weight loading on the parts.