API STD 676 2009 pdf download.Positive Displacement Pumps—Rotary.
1 Scope This standard covers the minimum requirements for rotary positive displacement process pumps and pump units for use in the petroleum, petrochemical, and gas industry services. Controlled-volume pumps, hydraulically driven pumps and positive displacement reciprocating pumps are not included (see API 674 for positive displacement reciprocating pumps and API 675 for controlled-volume pumps). For rotary positive displacement pumps in auxiliary services (e.g. lube oil systems), manufacturer’s standard with demonstrated experience is acceptable. Annex A contains datasheets which purchasers are encouraged to use (informative). Annex B provides guidance for factors affecting twin screw efficiencies (informative). Annex C contains an inspector’s checklist (informative). Annex D contains forms which may be used to indicate vendor drawing and data requirements (VDDRs) (informative). Annex E gives guidance regarding net positive suction head (NPSH) vs net positive inlet pressure (NPIP) (informative). Annex F gives guidance on pulsation and vibration control techniques (informative). Annex G provides a typical piping and instrumentation diagram for multiphase pump (MPP) skids (informative). This standard requires the purchaser to specify certain details and features. A bullet ( ) at the beginning of a paragraph indicates that either a decision by, or further information from, the purchaser is required. Further information should be shown on the datasheets (see example in Annex A) or stated in the quotation request and purchase order. 2 Normative References 2.1 The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. API Specification 5L:2007/ISO 3183 1 , Specification for Line Pipe
3 Terms and Definitions For the purposes of this standard, the following terms and definitions apply. 3.1 acoustical simulation Process whereby the acoustical characteristics of fluids and the rotary pump dynamic flow influence are modeled. 3.2 alarm point Preset value of a measured parameter at which an alarm is activated to warn of a condition that requires corrective action. 3.3 anchor bolt Bolt used to attach the baseplate to the support structure (concrete foundation or steel structure). 3.4 baseplate Component on which the drive train and pump are bolted, which is then fastened to the support structure using anchor bolts. 3.5 capacity Flowrate.
3.6 certified material test report CMTR Certified report documenting the actual chemical composition and/or physical properties of critical materials. 3.7 datum elevation Elevation to which values of NPSH are referred (concrete foundation or steel structure to which the baseplate is attached); also see paragraph defining NPSH (see 3.38). 3.8 depressurization valve Valve, external to the MPP, used to relieve the gas pressure within the MPP package to a blow-down system or flare. NOTE Also known as a blow-down valve. 3.9 design Manufacturer’s calculated parameter. NOTE A term used by the equipment manufacturer to describe various parameters such as design power, design pressure, design temperature, or design speed. It is not intended for the purchaser to use this term. 3.10 differential pressure Change in energy of the pumped liquid due to its pressure change in the pump. Typically, the discharge pressure minus the suction pressure. 3.11 discharge pressure Energy of the pumped liquid due to its pressure as measured immediately downstream of the pump discharge flange. 3.12 displacement Volume transferred from the suction to discharge per revolution of the rotor(s). In pumps incorporating two or more rotors operating at different speeds, the displacement is the volume transferred per revolution of the driving rotor. Displacement depends only on the physical dimensions of the pumping elements. 3.13 drive train components Item of the equipment used in series to drive the pump (e.g. motor, gear, turbine, engine, fluid drive, clutch). 3.14 fail safe System which will cause the equipment to revert to a permanently safe condition (shutdown and/or depressurized) in the event of a component failure or failure of the energy supply to the system.