Scope and application

This standard is the DNV standard for the design of machinery components and structures for the complete wind turbine. The standard assumes a typical wind turbine and a design lifetime of 20 years. However, the content and the requirements stipulated in this standard can be transferred to all types of wind turbines.

Machinery components and structures for wind turbines shall be designed with the aim that:

— the maintaining of normal operational conditions will be ensured

— the safety of personnel and installations will be ensured and risks of injury to human life will be reduced to a minimum

— the machinery components and structures will reach the expected design life time

— sufficiently high reliability is reached for the entire system.

This standard covers:

— materials

— corrosion protection

— bolted connections

— machinery structures

— bearings

— blade pitching systems

— yaw systems

— mechanical brakes and locking devices

— couplings

— elastomer bushings

— hydraulic systems

— gearboxes

— nacelle covers and spinners.

This standard specifies requirements for the design of machinery components and structures for wind turbines intended to ensure a safety level that is deemed acceptable for such systems. Some of these requirements imply certain constraints on the designs that reflect the current practice in the industry and established principles of design and construction of wind turbines. Alternative designs and arrangements that deviate from these requirements may be accepted provided that it is documented that the level of safety is at least as high as that implied by the requirements of this standard. Technology qualification procedures may be helpful in this context.

Guidance note:

A recommended method for identifying risk control options and documenting the safety of alternative designs and arrangements is given in DNV-RP-A203.