Frank Mohn's deliveries to Petrobras include these diesel hydraulic firewater pumps for the P-31 floater.When planning pump facilities it is important to recognize that production ships are not the same as tankers. The offshore pump can be ten times the size of the marine pump, which creates difficulties if installed in the machinery space. And although a tanker comes to port for maintenance, the FPSO remains permanently on the field.
One solution for the installation problem is to use submersible pumps and a caisson. This solution has been adopted on a number of FPSO projects, including Conoco's Banff, Amerada Hess's Bittern, Shell's Curlew and Woodside's Laminaria. On Statoil's Norne vessel, the pumps and caisson were retrofitted at sea.
In the case of tankers being converted into FPSOs, it may be difficult to install a caisson. In this type of case, Frank Mohn provides a submersible pump solution without the caisson. Instead, the pump hangs over the side of the vessel.
Latin America
Frank Mohn Flatoy has become a regular supplier of firewater and seawater lift pumps to Petrobras production floaters. In just four years, the Bergen-based company has delivered 23 firewater pumps and seven seawater lift pumps to 11 of the state oil company's production units, reports German Nilsen, sales manager, Americas. The latest order, which was confirmed in July, is for two fire-water pumps, each of 2,000 cu meters capacity, for the P-40 production ship. These are due for delivery in April.Last year, Frank Mohn delivered three seawater lift pumps for caisson installation to Amec for the P-36 (ex Spirit of Columbus) semisubmersible production platform; two diesel-hydraulic firewater pumps and one diesel-direct firewater pump to Modec for the P-37 production ship; and one diesel-hydraulic and one diesel-direct firewater pump to AESA for the P-47 floating storage unit. The P-37 and P-47 pumps are all skid-mounted.
The company has opened a service office in Rio de Janeiro.
Also, Frank Mohn has a number of orders for emergency offloading packages from Pemex. The state oil company has also purchased the supplier's cargo pumps for its products tankers, Nilsen says. Mexico does not represent a big market where floaters are concerned - it has three floating storage and offloading units, but no production floaters.
Last year, the supplier sold water injection pumps to a BP operation in the Pedernales region of Venezuela, a mangrove area where production takes place using barges. At 350 bar, these are the highest pressure pumps the company has ever supplied, Nilsen says.
North Sea
The North Sea continues to be an important proving ground for Frank Mohn. In mid-1998, the company delivered three fire-water pumps and three sea-water lift pumps for Elf's Elgin process platform. The pumps are installed in three A-60 rated modules - in the case of fire, the modules will seal themselves off and the pumps will continue operating for as long as the fuel supply lasts.By employing its caisson-free concept, it was possible to save a total of 120 tons on a weight-sensitive project, says oil and gas sales manager Frode Hjelmeland. The weight savings are achieved by Frank Mohn's concept using integral power tubing, allowing the pumps to be installed without the large-diameter caissons normally used.
Each of the pumps is driven by a 2 MW driver. A time and labor-saving feature is that the condition monitoring of the pumps is performed through the lube oil system.
Where required, the company also supplies systems packages. Last summer it delivered an 89-ton systems package for Esso Norge's Jotun production ship, comprising two pumps for produced water injection with filtration systems. All the equipment is mounted on a common skid with valving and instrumentation. A similar - but at 312 tons, much heavier - systems package was supplied to Statoil's Norne production ship.
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