Harley’s Latest tug begins service
The latest addition to the Harley Marine fleet is now completing sea trials and preparing to enter service. The “M/V Earl W. Redd” will be operated under the flag of the Olympic Tug & Barge unit of Harley. The 120 foot tractor tug, built by Diversified Marine Inc. in Portland, Oregon, and named after the father of Diversified President Kurt Redd, is slated to enter service providing unrestricted coastal towing along the West Coast of the United States. Tier IV-compliant CAT engines coupled to Rolls-Royce “Z-drives” power the tug, delivering an expected bollard pull capability of 75 tons.
Harley Marine once again selected Markey Machinery to supply the deck equipment for this vessel. The tug is equipped with a two-winch suite of equipment consisting of a Markey TESD-34B-100HP doubledrum electric towing winch, and a DEPC-48-50HP electric bow hawser winch with Render/Recover.
The TESD-34B-100HP towing winch is arranged to hold 2500 feet of 2-1/4” diameter wire rope on the starboard drum, and 1500 feet on the port drum. Barrel layer performance is rated at 193,000 lbs (87500 kgs) at stall; 129,000 lbs (58500 kgs) at 22 FPM (6.7 MPM); and 55,000 lbs (24900 kgs) at 43 FPM (13 MPM). The brake has a maximum holding capacity of 645,000 lbs (292500 kgs). Powered by a 100 HP TENV inverter-duty electric motor controlled by a variable frequency drive, the winch can provide full
torque at continuous stall. The winch also includes a hydraulically powered emergency “come home” drive motor in the event of electrical failure.
The DEPC-48-50HP bow hawser winch will hold 500+ feet (152 meters) of 9” Synthetic HMPE line in 8 layers. The mid-drum (5th layer) performance rating is 22400 lbs (10100 kgs) at 100 FPM (30 MPM). Light-line (high speed) ranges from 107 to 291 FPM (32 to 88 MPM). Brake capacity exceeds 612,000 lbs (277000 kgs). The winch utilizes Markey’s proven Render/Recover technology to allow tug positioning while automatically maintaining an adjustable inhaul/payout constant-tension on the line. It also includes a “Freewheel” feature allowing for fast line payout or emergency escape.
In order to minimize the impact of “below-deck” equipment on available space, (along with system cost), the two winches share the 100 HP towing winch VFD drive panel, while having discrete wheelhouse controls for each winch. When the hawser winch is selected to operate, the VFD is programmed to supply 50HP power and control to the winch’s 50HP motor.