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ESL Labs’ Medium Weight Shock Machine tests the limits
When the Canadian government awarded Nova Scotia’s Irving Shipbuilding the 2011 contract to build the combat package, the largest portion of work under the National Shipbuilding Strategy (NSS), the procurement promised to not just end the boom-and-bust cycle of shipbuilding jobs but also usher in new Canadian development - and the engineering, manufacturing and hi-tech jobs that come with it - for Canadian suppliers, from electronics to propulsion systems, requiring domestic design, manufacturing and test engineering expertise.
Irving Shipbuilding’s supply chain now stretches from coast-to-coast, and the National Shipbuilding Strategy supporting around 9,400 jobs annually across Canada, with 4,300 of those 9,400 jobs located in Nova Scotia.
With the work nearing completion for the six Arctic and offshore patrol ships, and plans turning toward the River-class destroyer series, ESL Labs, a Dartmouth, Nova Scotia test facility, has invested $10M in upgrades, including installation of a Medium Weight Shock Machine (MWSM), one of only two in Canada, and just 18 in the world, for testing the ability of equipment and system installations onboard to withstand the effects of nuclear or conventional weapons.
“The navy needs to ensure that shipboard equipment can survive the severe shock loadings that could be experienced during combat conditions, for example due to the impact of nuclear or conventional weapons, “ explains Steve Mercer, P.Eng., ESL Labs General Manager.
“The shock that’s generated on that machine emulates the impact that equipment receives inside the vessel (under attack). We want to make sure the equipment remains operational and doesn’t become a hazard.”
The fifteen River-class destroyers (the first three are named ‘Fraser, ‘ ‘SaintLaurent, ‘ and ‘Mackenzie’) will replace both the retired Iroquois-class destroyers and patrol frigates. They will ensure that Canada can continue to monitor and defend its waters and contribute to international naval operations.
Shock testing is essential. Critical naval ships and submarine equipment for combat and survival must continue to function after explosions. Shock tests ensure the equipment’s mounting is secure and that equipment does not become hazardous after an underwater blast.
Shock tests simulate non-contact underwater explosions in combat situations and apply to all critical equipment installed on Royal Canadian naval ships expected to be in harm’s way.
The MWSM is used to simulate underwater explosions and the impact on continued operation of both critical systems and equipment. “Different shock loads are generated on equipment in different mounting orientations to ensure the equipment remains operational and functioning at optimal capacity,” says Mercer.
Our comprehensive Canadian manufacturing and testing capabilities, which underpin the entire Canadian supply chain, directly supports the emphasis on national sovereignty
“Shock testing does more than just ensure combat readiness and protect personnel; it also delivers significant long-term cost savings. By providing valuable feedback to manufacturers, testing helps reduce future repairs and downtime, avoid expensive retrofits, and ultimately extend the lifespan of equipment. “
Many engineering challenges were overcome in the installation of the MWSM in the 30,000 sq. ft. Dartmouth facility. It was a complicated assembly - with the last MWSM built in the United States in 1993. ESL Labs points out that the MWSM drawing package dates to 1961. Materials and construction methods have changed greatly since 1961, so a substantial amount of re-engineering was required.
The greatest challenge was with the concrete assembly. The MWSM counter weight is 34,300 kg of concrete and steel embeds. sitting on eight springs. The assembly sits on eight springs within the outer foundation of 157,200 kg of concrete and steel embeds. Due to building constraints, the counterweight needed to be cast in place. This required the concrete to be cast and the assembly grouted with the springs in compression, with the springs being released once the concrete had cured. “Our task involved a double challenge: managing immense material weight while also adhering to critical time limits.”
With support of a subject matter expert - a mechanical engineer from the US with more than 35 years of experience in shock testing - the MWSM was 100% re-engineered, fabricated and assembled in Nova Scotia. The project required significant mechanical, civil & electrical engineering design and construction support:
• Stantec Engineering (Dartmouth) completed the drawing package, including the foundation, piece parts, assembly and controls.;
• Castone Construction (Dartmouth) undertook the concrete assembly; MacGregors Industrial Group (Thorburn) took care of the manufacturing of components and assembling of the mechanical and electrical components; and
• Harbourside Project Management oversaw the overall Project Management.
The National Shipbuilding Strategy ensuring public money stayed in Canada has meant jobs growth across Nova Scotia. “The expansion of our military testing, particularly for naval applications, is occurring at a critical time. ESL Labs takes great pride in our role of delivering mission-critical systems and equipment.” As the NSS continues, ESL Labs expects to more than double its workforce in the next 3-5 years.
