Innovative Way of Testing Underway Replenishment Systems Using Water Weights

The common methodology adopted to test the Underway Replenishment (UNREP) equipment aboard ship is to utilize a dockside or floating crane, a set of test weights and a preventer line to control the angle of the test loads applied, and to ensure that the suspended weights from the crane are kept truly vertical so as not to overload the crane.

The preventer line has to be attached to a strong point on the wharf or floating crane barge, and has the potential to cause a mishandled crane to be overloaded and damage the jib or slewing ring. The test equipment and rigging also has to take into account the height difference between the deck level, test points, availability of strong points for fixing the preventer lines and availability of a suitable crane able to support the full test weight. This methodology is traditionally time consuming and expensive.

All of these problems can be overcome by the use of a gin pole acting as a strut to convert the water Weights into the required pull on the UNREP pad-eye or sliding block. Altering the length of the gin pole would facilitate testing angles in the vertical plane and fixed rigging points on the vessel with adjustable rigging wires would permit the tests to be conducted at a variety of angles fore and aft of a beam, all with the minimum of difficulty.

In addition, the use of a gin-pole would preclude the necessity for a crane to support the test weight other than for rigging the test. This removes the likelihood of shock loading the crane from the impulse of a dropped load should the item of equipment being tested fail. The use of water bags will allow the gradual application of load, together with monitoring key components of the system during the test, thus ensuring that UNREP testing does not create a hazardous situation.

System Description
• Adjustable length gin pole and Water Weights bag
• Load attachment plate
• Base plate and deck load spreader
• Lateral restraint rigging

The gin pole is erected with its rigging to fixed points on the ship such that the gin pole acts to strut the test load off the vessel and convert the vertical test load to a horizontal pull. The UNREP testing can then be carried out very simply by adjusting the length of the gin pole with the addition of intermediate sections to achieve the ±30º vertical alignment about mid-position and by adjusting the lateral restraint rigging to alter the fore and aft alignment of the test.

The use of a gin pole allows the resolution and transfer of the test loads into the internal structure of the vessel by the base plate and deck load spreader without the need for a preventer line to a dock side fitting or bollard. Load monitoring and measurement can be integrated with the gin pole and rigging to ensure the specified test loads are being applied to the UNREP system to meet the design intent.

Water Weights also has the ability to provide a full monitoring suite of instrumentation during testing to determine the ongoing structural integrity of the UNREP system. Typical techniques include the use of Acoustic Emission fingerprinting and monitoring during load applications, instrumented load pins in the primary load paths, rotary encoders for accurate measurement of line angles and telemetry load links able to remotely report the loading regime under which the test is being carried out.

Note: The company is in the process of fitting a full set of monitoring equipment to a Royal Navy Type 23 frigate to monitor the actual loads in real time experienced by the Replenishment At Sea (RAS) system during a period of sustained use under a variety of sea states, load transfers, connected platforms and operational environments. This is part of a data gathering exercise to support the development of a higher load capacity and throughput RAS system for the Royal Navy future carrier project.

For more info visit: http://www.waterweightsinc.com/files/files/US_Downloads/UNREP_Testing.pdf

From the pages of OSHA; Cranes and Derricks in Construction Final Rule

The U.S. Department of Labor's Occupational Safety and Health Administration (OSHA) released a historic new standard, addressing the use of cranes and derricks in construction and replacing a decades old standard. The significant number of fatalities associated with the use of cranes and derricks in construction and the considerable technological advances in equipment since the publication of the old rule, issued in 1971, led the Labor Department to undertake this rulemaking.

In 1998, OSHA's expert Advisory Committee on Construction Safety and Health (ACCSH) established a workgroup to develop recommended changes to the current standard for cranes and derricks. In December 1999, ACCSH recommended that the Agency use negotiated rulemaking to develop the rule. The Cranes and Derricks Negotiated Rulemaking Committee (C-DAC) was convened in July 2003 and reached consensus on its draft document in July 2004. In 2006, ACCSH recommended that OSHA use the C-DAC consensus document as a basis for OSHA's proposed rule, which was published in 2008. Public hearings were held in March 2009, and the public comment period on those proceedings closed in June 2009.

* The rule becomes effective 90 days after August 9, 2010, the date the final rule was published in the Federal Register. Certain provisions have delayed effective dates ranging from 1 to 4 years.
* The final rule was published on August 9, 2010 by the Federal Register, and can be found at http://www.osha.gov/FedReg_osha_pdf/FED20100809.pdf.
* A copy of the regulatory text is available at: http://www.osha.gov/doc/cranesreg.pdf
* This new standard will comprehensively address key hazards related to cranes and derricks on construction worksites, including the four main causes of worker death and injury: electrocution, crushed by parts of the equipment, struck-by the equipment/load, and falls.
* Significant requirements in this new rule include: a pre-erection inspection of tower crane parts; use of synthetic slings in accordance with the manufacturer's instructions during assembly/disassembly work; assessment of ground conditions; qualification or certification of crane operators; and procedures for working in the vicinity of power lines.
* This final standard is expected to prevent 22 fatalities and 175 non-fatal injuries each year.
* Several provisions have been modified from the proposed rule. For example:
o Employers must comply with local and state operator licensing requirements which meet the minimum criteria specified in § 1926.1427.
o Employers must pay for certification or qualification of their currently uncertified or unqualified operators.
o Written certification tests may be administered in any language understood by the operator candidate.
o When employers with employees qualified for power transmission and distribution are working in accordance with the power transmission and distribution standard (§ 1910.269), that employer will be considered in compliance with this final rule's requirements for working around power lines.
o Employers must use a qualified rigger for rigging operations during assembly/disassembly.
o Employers must perform a pre-erection inspection of tower cranes.
* This final rule requires operators of most types of cranes to be qualified or certified under one of the options set forth in § 1926.1427. Employers have up to 4 years to ensure that their operators are qualified or certified, unless they are operating in a state or city that has operator requirements.
* If a city or state has its own licensing or certification program, OSHA mandates compliance with that city or state's requirements only if they meet the minimum criteria set forth in this rule at § 1926.1427.
* The certification requirements in the final rule are designed to work in conjunction with state and local laws.
* This final rule clarifies that employers must pay for all training required by the final rule and for certification of equipment operators employed as of the effective date of the rule
* State Plans must issue job safety and health standards that are “at least as effective as” comparable federal standards within 6 months of federal issuance. State Plans also have the option to promulgate more stringent standards or standards covering hazards not addressed by federal standards.
* OSHA will have additional compliance assistance material available within the next month.

July 28, 2010

http://www.osha.gov/as/opa/cranesderricks-factsheet.html