$3M Saved Using Water Bags for Weight Testing

Tuesday, August 21, 2001
The Navy has recently begun using water bags accomplishing periodic weight tests of boat davits. A result of a teaming effort between NAVSEA, NAVSEA Philadelphia-SSES and FTSCLANT, this innovation will save the Navy over $3 million per year compared to traditional methods. In the past, tests using concrete block or steel weights required a pier side or barge crane plus four-six individuals, cost as much as $20 thousand and required up to eight hours. Using water bags is simple. A flexible container is filled with water, acting as the test weight. Water supplied from the ship fire main fills the bag to the required weight. (Remember "A pint's a pound the world around"?) A wireless load cell shackle connected between the bag master link and the davit hook provides an accurate reading as the bag fills. Adding or draining water adjusts the weight. Once the operation is complete, the container is drained and packaged for storage. Since it can be packed up at the relatively small size of 175 - 300 lbs, the process requires no crane supporting or positioning the bags on the davit. Only about three workers are needed over a three-hour job. Cost savings constitute the greatest advantage. The Navy spends between $3.6 and $5.2 million per year for weight tests. Estimated annual costs will decrease approximately $560K per test by eliminating the need for a crane plus reduced labor and time, producing savings of over $3 million. Safety is enhanced, as physical handling of large weights is no longer necessary. Scheduling flexibility increases for the testing activity and the TYCOM, ship's force and FTSC. Without the need to schedule a crane, tests can be accomplished with very little advanced notice. Greater flexibility generates additional savings that defy accurate calculation. Funding obtained from NAVSEA's Engineering for Reduced Maintenance Program enabled the teaming effort between NAVSEA, NSWCCD-SSES and FTSCLANT. The first step called for identifying a manufacturer whose product was safe, functional and reliable. Water Weights Inc. was quickly identified. The second step entailed resolving physical size constraints for the bags because of unique test requirements associated with boat davits. Unlike many other hull and deck machinery systems, boat davits must inhaul the test weights to the fullest inboard point, ensuring the davit winch and structural members are subjected to loading experienced during actual conditions. This brings the weights within the shell of the ship, requiring shapes small enough to avoid deck obstructions. Water Weights Inc. was able to modify "off the shelf" bags to fit. The final step was development of operational and maintenance procedures for incorporation into manuals and a training video. It shows the principle of operation as well as the test. The footage was taken and the operational and maintenance procedures "proofed in" during actual tests on USS GEORGE WASHINGTON (CVN 73), USS BARRY (DDG 52), and USS MOUNT WHITNEY (LCC 20). - (By Tom Warring, Public Affairs Officer, Naval Station Warfare Center, Carderock Division)


Esvagt Makes Vestdavit MissionEase First Choice for Mission Bay

Norway-based boat system and davit-handling specialist Vestdavit has secured a breakthrough order for its unique MissionEase multi-boat handling solution for mission bays,

DNV GL Backs John Laing on First Offshore Wind Investment

DNV GL successfully completed its due diligence work of the offshore wind farm “Nordergründe” in the North Sea, reviewing and quantifying the technical risks of the project.

GoM Operators Evacuating Ahead of Storm

Offshore oil and gas operators in the Gulf of Mexico are evacuating platforms and rigs in the path of Tropical Depression No. 9.   The Bureau of Safety and Environmental

Maritime Careers / Shipboard Positions Maritime Standards Naval Architecture Navigation Offshore Oil Pod Propulsion Ship Electronics Ship Simulators Shipbuilding / Vessel Construction Winch
rss | archive | history | articles | privacy | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.0670 sec (15 req/sec)