Large machine maintains continuous process

Edited by the Engineeringtalk editorial team Jun 10, 2004

WEG has supplied one of its medium-voltage H series motors for use on a continuous distillation process at Esso's Fawley refinery in Southampton.

WEG has supplied one of its medium-voltage H series motors for use on a continuous distillation process at Esso's Fawley refinery in Southampton.

Rated at 1.1MW, 3.3kV, the H Series motor is operating 24 hours a day 365 days a year driving a large compressor, which feeds one of the important pipestills at the refinery.

Esso's Fawley refinery is the largest in the UK and one of the most complex in Europe.

Situated on Southampton Water, it has a modern marine terminal that handles around 2000 ship movements and 22Mt of crude oil and associated products every year.

The refinery processes some 300,000 barrels of crude oil a day and supplies over 15% of all oil products used in the UK.

Central to the production at Fawley is a continuous distillation process, undertaken using large distillation columns known as pipestills.

These are fed with crude oil, which is heated to around 600C in a boiler using superheated steam and then subjected to a complex fractionation process.

This causes the oil to separate into different products at various levels of the pipestill - typically, heavy gas oil, lubricating oil, diesel, kerosene, gasoline, Naptha and gas.

WEG's H series motor is an integral part of the distillation process.

The motor, a 1100kW, 1500rev/min unit, coupled via a step-up gearbox to drive a feed compressor 10,000rev/min, 24 hours a day, 365 days a year.

Because of the nature of the electrical system characteristics, the WEG motor is equipped with a fault rated phase segregated terminal box rated to withstand 250MVA for 0.25s at 3.3kV.

In addition, insulated, self-contained Renk sleeve bearings are fitted to ensure continuous and maintenance-free operation.

These bearings are insulated to prevent circulating shaft currents within the motor, which could result in electrical discharges and bearing damage.

The high levels of protection available on the H line machines are the result of WEG's application experience in some of the toughest oil, gas and petrochemical markets in the world.

This experience is also evident in the motors' basic design, H line units being extremely robust machines with cast-iron frames, corrosion resistant finishing and galvanised mounting components.

As a result, they are ideally suited to operating conditions encountered in the most arduous industrial and process applications.

In these applications the combination of an internal cooling circuit, external cooling fins and high-efficiency cooling fans guarantees a favourable temperature gradient within the motor, which both protects and extends the operating life of the motor.

"WEG is probably best known worldwide for its low voltage range of motors, but with rapidly increasing sales of our medium and high voltage machines that perception is changing", says Colin Cox, WEG Product Manager for MV and HV Machines.

"We have proven that our large machines can offer the highest levels of reliability and performance in the most severe industrial, processing and petrochemical applications, and we can back them up with 24/7 local service and support where required".

"This message is certainly getting through because, although a recent newcomer to the UK with large machines, WEG is already accounting for 8% of the market".