Dri-Prime pump improves waterline installations in Antigua
Godwin HL Series High Head Dri-Prime® pump's 20-inch impeller generates greater pressure at greater depth, which accounts for the successful installation of a power cable and waterline in Antigua.
Godwin HL Series High Head Dri-Prime® pump’s 20-inch impeller generates greater pressure at greater depth, which accounts for the successful installation of a power cable and waterline in Antigua.
Stephanie Morgan, Bill Wenger
Marine contractors specializing in applications, such as jetting on dredge heads and hoppers, and installing sub sea waterlines and power and communication cables require pumps that can push a reasonable amount of water at extreme discharge pressures.
According to Project Manager Tim Paquette for Durocher Marine Division: “In underwater cable installation especially, you can never have too much volume or pressure. Engine speed can be adjusted to changing sub bottom conditions, but it is a great feeling knowing that when burial conditions become difficult, the Godwin HL160M pump will always get the job done.” Durocher Marine Division, part of the Kokosing Construction Company, is based in Cheboygan, Michigan, USA.
The eductor sled jets the cable out.
Paquette and his Durocher Marine Division crew put the HL160M to the test in a power cable and waterline installation in the West Indies on the Caribbean island of Antigua last July 2005. In three months, Durocher buried 13,000 feet of 15KV power cable and four-inch waterline using an eductor (cable burial sled) powered by two Godwin HL160M pumps. The 15KV power cable was 3.1 inches in diameter and weighed 6.5 pounds per foot, while the water line measured 5.3 inches in diameter and weighed four pounds per foot. These two materials were bundled together with a ballast cable weighing an additional 2.9 pounds per foot. All three materials were pulled from their reels by a lineal cable machine and banded together at the end of the barge just before being submersed. The cables were laid using 1.5-inch wire rope for ballast and roughly 5,300 feet of the cable/waterline bundle, which was covered with protective mats to prevent damage from boat anchors and possible danger of flotation should the bundle ever separate. The barge moved on anchors along a pre-determined lay route, stopping every 1,000 feet so that divers could ensure proper placement of the installation.
With the bundles placed securely in position, the route was retraced for burial by the eductor. Using a combination of water and air, the eductor created a trench in which the cable bundles could be buried. Divers observed as the HL160M pumps worked to move 3,600 gpm at 206 psi, allowing the eductor to cut a 24-inch wide trench approximately 24 to 72 inches deep, depending on bottom conditions.
Closeup of the eductor sled and cable
Antigua posed several environmental challenges, including difficult bottom conditions. The eductor encountered surfaces varying from coral rock and soft limestone to sand, posing a challenge for burial. In addition, the availability of equipment, tools, and supplies was limited due to the remote location. These challenges were met head-on by the HL160M pumps.
The Godwin HL160M Dri-Prime pump overshadows its multi-stage competitors because it does not need to be manually primed and was designed to be more portable/flexible for users. The secret behind its performance is its 20-inch diameter impeller. Where multi-stage pumps use multiple, smaller impellers, the HL160M pump’s 20-in. impeller is capable of generating greater pressure at greater depths—a perfect fit for marine construction.
Stephanie E. Morgan is a technical writer for Godwin Pumps of America, Inc., based in Bridgeport, New Jersey, USA. Bill Wenger is a project originator and overall manager for Durocher Marine Division, based in Cheboygan, Michigan, USA. For more information, email firstname.lastname@example.org