National Oilwell Varco - Brushless Synchronous Generators

National Oilwell’s Baylor brushless synchronous generators are built for extreme duty. They are manufactured using the latest technology and heavy-duty construction designed for long life during oilfield drilling applications, including heavy motor starting and non-linear S.C.R. Drives.

They are constructed to withstand severe environmental conditions of heat, high humidity and contaminated ventilation. Designed specifically for the oil and gas industry, the line of generators features:

• Class F, fully taped, form wound coils
• Vacuum Pressure Impregnation
• Heavy-duty dove-tailed rotor construction
• Fabricated, copper damper circuit
• Epoxy layer wound fields

CONSTRUCTION

National Oilwell’s Baylor generators are constructed from the highest-grade materials. The stator iron is low loss electrical steel with slot combinations and skewed slots designed to reduce harmonics and perform exceptionally well in SCR duty and while starting large motors.

The stator frame is a heavy-duty fabrication designed to withstand the forces caused by the frequent relocation of drill rigs and around the clock running. Units are two bearing construction with robust spherical roller bearings designed for a 40,000 hour minimum life.

Rotor construction is compact and rugged with brushless exciter components located outboard of the rear bearing to allow easy access for maintenance. All rotors are dynamically balanced to exacting standards and are capable of 125% overspeed without damage. Enclosure is drip proof guarded (IP22) with optional water-air-cooled and air-air-cooled enclosures available. Inlet air filters are available for extreme environments.

Cooling air ventilation inlet is at the rear of the generator and is radially discharged at the front. Units are designed for operating in ambient temperatures of 50ºC or greater and remain within temperature limits of insulation systems.

QUALITY

National Oilwell’s Baylor brushless synchronous generators are manufactured to exacting internal standards and meet or exceed NEMA, IEEE, ANSI and IEC requirements. In addition, third party certification to ABS, DNV, LLOYDS, Bureau Veritas, etc. is also available.

National Oilwell’s Sugar Land, Texas facility has been continuously certified to ISO 9001 standards since 1995 and receives surveillance audits from ABS, Evaluations, Inc. every six months.

WOUND STATOR ASSEMBLY

Wound Stator Assembly consists of heavy form wound coils with fully taped and insulated magnet wire, completely processed with multiple Vacuum Pressure Impregnation procedures to assure maximum dielectric and environmental protection. Both ends of the three phase stator windings are brought out to the terminal box and connected to bus bars. The neutral connection is made up in the box and provisions are made for differential protection, if required.

ROTOR ASSEMBLY

Rotor Assembly is made of a laminated rotor spider and individual field poles attached to the spider with robust dovetails inserted into slots in the spider. The field poles are wound with insulated copper wire and layers of epoxy to provide maximum bond strength. A full copper damper circuit is interconnected from pole to pole to provide superior paralleling and transient characteristics.

SERVICE

National Oilwell’s worldwide distribution, warehousing and service centers provide comprehensive service, parts and warranty support for our complete line of drilling products. In addition, we stock critical generator components at our authorized service centers located in all the principal drilling regions of the world.