This standard covers the minimum requirements for general-purpose steam turbines for refinery service. These requirements include basic design@ materials@ related lubrication systems@ controls@ auxiliary equipment@ and accessories. Note: A bullet (?) at the beginning of a paragraph indicates that either a decision is required or further information is to be provided by the purchaser. This information should be indicated on the data sheets (see Appendix A): otherwise@ it should be slated in the quotation request or in the order. ? Steam turbines are classified as general- or special-purpose according to service requirements. The purchaser will specify the type of turbine that is best suited to his needs. General-purpose turbines are horizontal or vertical turbines used to drive equipment that is usually spared@ is relatively small in size (power)@ or is in noncritical service. They are generally used where steam conditions will not exceed a pressure of 700 pounds per square inch gauge (48 bar gauge) and a temperature of 750??(400?? or where speed will not exceed 6000 revolutions per minute. Special-purpose turbines are horizontal turbines used to drive equipment that is usually not spared@ is relatively large in size (power)@ or is in critical service. The use of special-purpose turbines is not limited by steam conditions or turbine speed. Requirements for special-purpose turbines are defined in API Standard 612.