Scope PURPOSE This standard covers the minimum requirements for general-purpose steam turbines. 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 stated in the quotation request or in the order. Steam turbines are classified general-purpose or special-purpose according to service requirements as described in 1.1.1.1 and 1.1.1.2. 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 non-critical service. They are generally used where steam conditions will not exceed a pressure of 48 bar (700 pounds per square inch gauge) and a temperature of 400 °C (750 °C) or where speed will not exceed 6000 revolutions per minute. Special-purpose turbines are those horizontal turbines used to drive equipment that is usually not spared, is relatively large in size (power), or is in critical service. This category is not limited by steam conditions or turbine speed. Requirements for special-purpose turbines are defined in API Standard 612. ALTERNATIVE DESIGNS The vendor may offer alternative designs. Equivalent metric dimensions, fasteners, and flanges may be substituted as mutually agreed upon by the purchaser and the vendor. CONFLICTING REQUIREMENTS In case of conflict between this standard and the inquiry or order, the information included in the order shall govern.