scope:

This standard covers the minimum requirements of special-purpose steam turbines for refinery services. These requirements include basic design, materials, and related lube-oil systems, controls, and auxiliary equipment.

Note: A bullet (•) at the beginning of a paragraph indicated that a decision by the purchaser is required. These decisions should be indicated on the data sheets (see Appendix A); otherwise they 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 1.1.2.1 and 1.1.2.2.

General-purpose turbines are those 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 intended for applications where steam conditions will not exceed 600 pounds per square inch gauge (41 bar guage) pressure or 750 ºF (400 ºC) inlet temperature, or both, and where speed will not exceed 6000 revolutions per minute. Requirements for general-purpose turbines are defined in API Standard 611.

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.