Page 39: of Maritime Reporter Magazine (January 2004)

Company Profile:

Propeller Cutting Technology to Free Entangled Lines

Marine Propulsion Annual

Since 1982, equipment manufac- tured by Spurs Marine has been pro- tecting propellers, shafts, seals and bearings from line entanglement.

Spurs cutter technique is a two-part assembly, with one or more rotary cut- ting blades and one stationary cutter blade - attached to a propeller hub, rope guard and/or strut. The purpose of this mechanism is to engage lines or debris entangled by the propeller and instantly cut them free with each revolution of the propeller.

Although the con- cept is simple, the technology involved is advanced in terms of design, materi- als and precision manufacturing, since the equipment must remain in opera- tion for a long period of time. Years of research and testing have resulted in a patented system that has been proven both reliable and effective. Precision machined, heat treating, hardened stainless steel metals, high tech hydrophilic and bronze bearings and corrosion control engineering are inte- gral features of Spurs cutter systems.

Routine maintenance during regular scheduled drydocking is recommend- ed. Under the U.S. Oil Pollution Act of 1990 (OPA 90), which imposes heavy penalties for oil leaks, the source of any leak as from a stern tube must be secured immediately. Spurs cutter systems help protect against pollution by guarding the running gear from oil seal damage and the use of Spurs, as an entanglement clearance system, will assist in the prevention of leaks before they can occur. Thousands of

U.S. Navy and Coast Guard vessels, as well as tankers and other cargo ships operating worldwide, currently use

Spurs cutter systems. Spurs use the propeller's rotation and inertial force to power the cutting action. As an offending line enters the propeller vor- tex, it is wound down toward the pro- peller hub. Without such equipment installed, it is at this point that the line would wrap itself tighter and tighter, entering into the space between pro- peller hub and rope guard, where oil seal damage occurs. Instead, the line is engaged by the rotary cutter blades and delivered to the stationary cutter blade. This sudden resistance, sensed by the stationary cutter, forces a cam action causing the blade to be pushed aft, meeting the rotating blade and severing the obstruction instantly.

The cutting force increases in direct proportion to the resistance sensed by the stationary cut- ter assembly.

Hydrophilic and bronze surface ! bearings maintain precise cutter posi- tioning when resistance occurs.

With each revolu- tion, the cutters pass each other gliding on a thin lubricating film of water within a few thousandths of each other, thus avoiding surface wear during long passages.

The typical large ship cutter is installed easily on vessels with oil seal bearings. With cutting blades that are comprised of stainless steel hardened to approximately 43-45 Rockwell C, this hardening characteristic ensures a high level of cutting ability. The resulting metal is reportedly the hard- est metal known to remain stable in saltwater. The remainder of the cutter parts are 316L stainless. This grade of metal is suitable where hardness is not required for performance, however, it is also very stable in saltwater. The box welded into the rope guard is made from 316L stainless and is easi- ly welded into the mild steel rope guard using stainless welding rod.

Zinc anodes are also welded on the underside of the rope guard.

The typical cutter system from medium to very large vessels can be fitted with forward propeller hub diameters from 228 mm-1,825 mm.

The stationary cutter assembly can be mounted directly onto a strut or into a rope guard. Cutter installation is quite versatile and can be adapted to almost any application. A new rope guard design is part and parcel of the overall cutter system design. Rope guards that are larger than the propeller hub and slope upward from the propeller hub guarantee line intrusion and must be redesigned.

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Washington State Ferries

Washington State Ferries

NEW 130-AUTO FERRIES

DESIGN AND BUILD CONTRACT NO. 00-6674

REQUEST FOR PROPOSALS

Washington State Ferries, a division of the Washington State Department of

Transportation (hereinafter called "WSF"), requests proposals from firms who wish to be considered for the following described project:

A Contract to design and build up to four (4) new auto ferries, through use of a modified Request For Proposals (RFP) process. Under the RFP, the prevailing shipbuilder and WSF will engage in a design and build partnership for the new auto ferries. Each ferry will have a capacity of 130 autos and 1202 passengers and crew.

Estimated Price Range for the shipyard Contract for all four auto ferries: $183,000,000 -$223,000,000.

In accordance with RCW 47.60.814, the vessels are required to be built within the boundaries of the state of Washington with warranty work performed in the state of Washington, insofar as practical. Additional information on these requirements is contained in RFP Volume IA.

The vessel Delivery Dates will be as follows:

VESSEL DELIVERY DATE 1st : Twenty-eight (28) months after commencement of Contract. 2nd : Thirty-six (36) months after commencement of Contract. 3rd : Forty-three (43) months after commencement of Contract. 4th : Fifty (50) months after commencement of Contract. (See Note 1.)

Proposers must be prequalifted by WSF in Class 81 work. "Vessel Construction and

Renovation", prior to submittal of a proposal. Additionally, Special Prequalification requirements apply to this RFR Certified Minority/Women Business Enterprises (M/WBEs) are encouraged to participate in the RFP process.

On or after December 3, 2003, interested parties may obtain Volume IA of the RFP pack- age from the WSF Contracts/Legal Services Department as shown below. The remain- der of the RFP package is scheduled tor issue in the Spring of 2004. At that time, the complete RFP packagc will be available upon request for the non-refundable fee of $200.00. Informational copies of the RFP package will be on file after that date at var- ious plan centers, WSDOT Support Services / Seattle SBA and at WSF. WSF will also post the RFP package on the following web site: www.wsdot.wa.gov/ferries/contracts.

Contracts/Legal Services Department Washington State Ferries 2911 2nd Avenue Telephone: 206.515.3606 (recording)

Seattle, Washington 98121-1012 Telefax: 206.515.3605

WSF assumes no obligation of any kind for expenses incurred by a respondent to this Notice or the RFP package.

Note 1: The fourth vessel has been approved by the Washington state legislature for the 2011-2013 Biennium. In the event that, prior to submission of bids for the

Construction Contract, the legislature advances the start date of a 4th vessel to the 2007-2009 Biennium, the Delivery Date for the 4th vessel will be as provided above

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January 2004 39