UNDEX is a term used to specifically define underwater explosions. UNDEX Shock Isolators can be used to protect vital equipment, weaponry, and personnel on ships and submarines, and therefore comply with shock survivability requirements that have been in place since the end of WWII.
The Importance of Naval Warfare
Throughout modern history, humans have relied on naval warfare as a key factor during times of war. Whether it is crossing oceans to reach enemy territory, battleship combat on lakes and rivers, or even transporting materials and equipment through smaller canals, controlling these waterways has proven to be a necessary strategy.
For the United States, the importance of a strong naval army became even more certain after the attack on Pearl Harbor in 1941, forcing the US to enter World War II. It was immediately clear that these battles at sea were different than those in the past with the development of the modern steel-armored battleships and submarines in the early 20th century. By the time the War concluded, the United States had become the world’s most dominant sea power and many lessons had been learned.
Setting Safety Standards
After World War II, the US and the UK looked back at some of the past battles and realized that new safety measures needed to be put in place in order to protect this new naval fleet. While mines and other blasts may not sink a ship, they can still cause significant damage to weaponry, equipment, and personnel on board.
The US Congress took action and incorporated a set of standards that would define a shock environment and establish the requirement for shipboard installations to withstand this shock loading due to the effects of nuclear or conventional weapons or environmental mechanical shock during operation. These would become Public Law, OPNAV Instructions, and NAVSEA Instructions, among others. They included the release of military standard MIL-S-901, which set the standard for high-impact shock testing and qualification of maritime systems, including mission and safety-critical computer systems and electronic equipment. For decades, these requirements were followed for equipment that was deployed onto US Naval ships and submarines.
More recently, in 2017, a new revision of MIL-S-901 was released designated as MIL-DTL-901E. This specification supersedes MIL-S-901D, and included detailed production and testing procedures, extensive diagrams and examples, and provisions for testing on land to help field needed equipment faster and more cost-effectively.
Shock Testing Equipment
In order to ensure that equipment is able to withstand a designated shock environment, a variety of shock tests per MIL-DTL-901E are performed. There are three different categories of testing. For lighter units under test, the standard methods include the use of lightweight and medium weight shock test machines. Alternate methods include the use of a Submarine Shock Test Vehicle (SSTV), among others. The standard heavyweight tests, on the other hand, are more elaborate and involve a floating barge test. The unit under test is placed on the floating barge, and a nearby charge is detonated underwater.
Past & Current Programs
Taylor Devices has a long and trusted history of developing custom solutions for UNDEX Shock Isolation that enables compliance with the aforementioned shock requirements. For over 40 years, we have worked on programs for the US Navy that provided UNDEX Shock Isolators for items including navigation systems, missiles and missile launcher systems, structural systems, electronic cabinets, among others.
One unique device that Taylor Devices provides that has been found to be very useful for these systems is our hard-centering liquid spring shock isolator. This device allows the equipment to remain rigid under some conditions such as wave action and under shipboard vibration but provides efficient shock isolation during shock events. During these shock events, the hard-centering feature will essentially unlock, thereby allowing the isolation system to attenuate the transient shock, and will then reposition the system to its exact position prior to the event. These isolators are arranged to provide 2DOF-6DOF isolation systems.
If you would like to learn more, or have further questions about our UNDEX Shock Isolation solutions, you can contact our team and we would be happy to help.