TECHNOLOGY - CARGO PUMPS Ice age pumps As the world faces up to the problems of global warming, engineers at the headquarters of Marflex are looking towards a new ice age. The management too, have responded, and are in the process of building 4,000 sq m of extra space in order to meet the challenge, reports Brian Warshaw. In October 2006, Russia's largest shipping company, Sovcomflot, placed an order with Samsung for three 70,000 dwt Ice Class 1A tankers. The tankers will be equipped with a dynamic positioning system, two 10 megawatt (MW) Azipod 360 deg rotatable propulsion units, two 13,180 kW main generators, helipad, and an Arctic bow loading system in which the hose connection is located well within the deck area. The vessels, which are 256 m in length, 34 m wide, and have a draught of 14 m, will be equipped with three main diesel-electric engines, which are capable of delivering propulsion totalling 24 MW. Able to sail in the harsh winter months, the vessels will be capable of ploughing through 1.57 m of ice without the assistance of an escorting icebreaker, and to operate in conditions of down to 45 deg C below zero. In the event of entrapment in the ice, the Azipod thrusters can be turned to move the vessel sideways to break free from the ice. These are the first ships to have the ability to move fore, aft, port and starboard; a factor included in the price of the vessel which is believed to have cost three-times that of a conventional oil tanker. Built to a dual classification of the Russian Maritime Register of Shipping LU6 class, and Lloyds Register 1A ice class, the vessels Pump warning device A simple, yet effective safety device has been developed by Pres-Vac Engineering of Allerød, Denmark, for installation on its deepwell cargo pumps. The device provides a warning when the main impeller bearing has been damaged or, as a result of long usage, has reached the stage where significant wear had taken place. Pres-Vac cargo pumps, which are electrically driven, feature a magnetic coupling between the drive shaft and the impeller. Unlike pumps that use a direct mechanical coupling to transfer power from the drive shaft to the pump head, and have always been subject to a small leakage, the magnet coupling ensures that the pump is leak-free. A static housing prevents lubrication oil from the drive shaft seeping out to contaminate the cargo, and conversely, the cargo cannot enter the drive shaft housing to dilute or replace the lubricating oil. The warning device consists of a nitrogen charged capillary tube, one end of which is fitted in the pump housing just below the impeller: the other end being attached to a small pressure container mounted on the pump deck. In the event of a failure in the main bearing, the impeller will oscillate, break the tip of the capillary tube, and the tube will operate under a 25 year timecharter. They will be used to transport oil from Varandey Island in the Pechora Sea, north-western Arctic Russia, to international markets, on behalf of Naryanmarneftegaz, a jointventure company between LukOil and ConocoPhillips. The three vessels are due to be delivered at the end of 2007, spring 2008, and in early 2009. The Varandey terminal is currently being expanded from 200,000 to 240,000 barrels per day, and due to shallow water in the area of the terminal, oil is loaded on the tankers from an offshore platform. Dutch deepwell pump manufacturer Marflex is supplying 42 deepwell pumping sets to will lose its pressure. The loss of pressure will immediately effect an indication and alarm on the control system. The pump will continue to operate safely on its secondary bearings in the period during which the pump is automatically shutting down. Pres-Vac's Eric Sorensen told TANKER<strong>Operator</strong> that the unit had been developed in response to the findings of an industry study into incidents that had occurred on chemical carriers. He said that at the moment it was an optional feature on Pres- Vac pumps, although it will be fitted as a standard on the company's next generation of single-stage magnetic driven pumps when they become available later this year. • Samsung in a contract worth nearly Eur6 mill. The pump sets for the first vessel are scheduled for delivery in June this year. Each vessel will be fitted with 10 cargo pumps, type MDPC- 250, with a discharge capacity of up to 800 cu m per hour, two slops-tank pumps operating to 500 cu m per hour and ballast tank pumps with a flow rate of 2,500 cu m per hour. The pumps are electrically driven and the controls are being supplied to Marflex by Siemens Netherlands. The Marflex deepwell pump consists of three major parts, an electrical drive motor that is installed on the deck, an oil lubricated drive shaft rotating in a separate pipe, and the pump head. It is claimed by the manufacturer that the drive shaft has a life exceeding 10,000 operating hours without maintenance, and is sufficient to last the 20 to 25 lifespan of an average tanker. Each of the 14 pumps fitted per vessel is fitted with EExd certified electric motors, which are designed to a particular specification for Marflex, and are linked to a series of variable drives. The variable Sinamics drivers, and Simatic S7 programmable logic controllers, deliver an electrical output of between 220 and 390 kW, which controls the pump discharge at flow rates within the range of 400 and 2,500 cu m per hour. Communication signals to the electric motors are facilitated by a Profibus interface, and the operations are managed from the ships' bridge using a Siemens designed panel. This solution enables the pumps to be directly controlled, and 36 TANKER<strong>Operator</strong> • March 2007
One pump One tank One supplier Frank Mohn AS, located outside Bergen in western Norway, is the leading supplier of submerged cargo pumps to the world tanker market. More than 32.000 Framo submerged cargo pumps are in service onboard some 2.000 tankers. In 2006 alone about 200 complete cargo pumping systems were commissioned. Framo Cargo Pumping System • Submerged Framo Cargo Pumps with individual capacities up to 2.000 m 3 /h • Submerged Framo Ballast Pumps with • Deck mounted Framo Cargo Heaters • Framo Hydraulic Piping System • Framo Control System Ballast Pumps Hydraulic piping Control Panel Hydraulic Power Unit (HPU) UPCOMING EVENT: Please visit us at Europort Eurasia, Istanbul. 25. - 29. April 2007 Cargo Heaters Cargo Pumps Bow thruster motor Hydraulics for deck machinery Frank Mohn AS P.O.Box 98 Slåtthaug - NO-5851 Bergen - Norway tel. +47 55 999 000 - fax +47 55 999 380 marine@framo.no www.framo.no HOUSTON BER GEN GOTHENBURG ROTTERDAM SHANGHAI PUSAN TOKYO SINGAPOR E “To a brave and faithful man nothing is difficult” RIO DE JANEIRO
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