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Reference Manual00821-0100-4810, Rev BCMarch 2006405 Compact Orifice Series and1595 Conditioning Orifice PlateFlow Test Data Book and Flow Handbookwww.rosemount.com

Reference Manual00821-0100-4810, Rev BCMarch 2006405 and 1595405 Compact Orifice Series and1595 Conditioning Orifice PlateFlow Test Data BookNOTICERead this manual before working with the product. For personal and system safety, and foroptimum product performance, make sure to thoroughly understand the contents beforeinstalling, using, or maintaining this product.Customer Central1-800-999-9307 (7:00 a.m. to 7:00 P.M. CST)National Response Center1-800-654-7768 (24 hours a day)Equipment service needsInternational1-(952) 906-8888The products described in this document are NOT designed for nuclear-qualifiedapplications.Using non-nuclear qualified products in applications that require nuclear-qualified hardwareor products may cause inaccurate readings.For information on Rosemount nuclear-qualified products, contact an Emerson ProcessManagement Sales Representative.Emerson Process Management satisfies all obligations coming from legislation toharmonize product requirements in the European Unionwww.rosemount.com

Reference Manual00821-0100-4810, Rev BCMarch 2006405 and 1595Table of ContentsSECTION 1405 Compact OrificeSeries and 1595Conditioning OrificePlateProduct Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2Structural Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2In-House Performance Testing. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2Independent Testing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2Product Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3SECTION 2Theory of OperationOverview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1Technical Detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1Compact Orifice Plate Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2Conditioning Orifice Plate Technology. . . . . . . . . . . . . . . . . . . . . . . . . 2-2SECTION 3Test Facilities and FlowTestsOverview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1Testing Laboratories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1Gravimetric Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2Flow Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2Run to Run Repeatability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2Meter Installed 2D Downstream of the Following Fittings . . . . . . . 3-3Run to Run Repeatability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4Single Elbow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-24Double Elbows In Plane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-28Double Elbows Out of Plane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-34Swirl Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-408 x 6-in. Reduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-50Butterfly Valve at 75% Open . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-54Gate Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-58SECTION 4Flow CalculationsRosemount 405C and 1595 Conditioning Orifice Plate . . . . . . . . . . . . 4-1Calculated Values and Variables Designations . . . . . . . . . . . . . . . 4-1Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2Rosemount 405P Compact Orifice Plate . . . . . . . . . . . . . . . . . . . . . . . 4-4Calculated Values and Variables Designations . . . . . . . . . . . . . . . 4-4Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5Flow Calculation Tables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6www.rosemount.com

Reference Manual405 and 1595TOC-200821-0100-4810, Rev BCMarch 2006

Reference Manual00821-0100-4810, Rev BCMarch 2006Section 1405 and 1595405 Compact Orifice Series and1595 Conditioning Orifice PlateProduct Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-1Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-2Product Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-3PRODUCT FEATURESThe Rosemount 405 Compact Orifice Series (standard and condition plateoptions) and 1595 Conditioning Orifice Plate primary flow elements maintainthe traditional strengths of orifice plate technology with improved features /performance.The strengths of the 405 include: More Economical than a Traditional Orifice Plate Installation Accurate and Repeatable Short Straight Run Requirements (405C - 2D Upstream and 2DDownstream) Self Centering Mechanism Based on ASME/ISO Corner Tap DesignThe strengths of the 1595 include: Based on the most common primary element in the world withestablished standards for manufacture and installation. Easy to use, prove, and troubleshoot Accurate and Repeatable Short Straight Run Requirements (2D Upstream and 2D Downstream) Based on ASME/ISO/AGA standardsThe Rosemount 405 and 1595 primary flow elements are sized usingRosemount's Instrument Toolkit sizing program. This program providesaccurate flow calculations using installation details and fluid properties for theflowmeter and presents this on a calculation data sheet or specification sheet.www.rosemount.com

Reference Manual00821-0100-4810, Rev BCMarch 2006405 and 1595TESTINGTests performed on the 405 / 1595 primary flow elements are divided intothree major categories: Mechanical and structural testing In-house performance testing Independent laboratory testingAll categories are on going and continue to be a part of the currentRosemount test program for the 405 / 1595 primary flow elements.Structural TestingRosemount performed integrity testing for: Allowable stress limits Hydrostatic Pressure Thermal Effects VibrationAt the following labs:In-House PerformanceTesting Hauser Laboratories, Boulder, CO Rosemount Vibration Laboratory, Eden Prairie, MNHundreds of flow tests were performed in the Rosemount flow laboratory in 2to 10-in. (50.8 to 254 mm) pipeline, using independently certified magneticflowmeters or the laboratory's gravimetric system as primary reference.Straight run requirements, run to run repeatability (w/ and w/o disassembly /re-assembly), pipe schedule, and sensitivity to centering are some of thein-house performance tests that were performed on the Rosemount 405PCompact Orifice Plate primary element.Baseline straight run, run to run repeatability (w/ and w/o disassembly /re-assembly), straight run requirements, pipe schedule, sensitivity tocentering, and gaskets are just a few of the in-house performance tests thatwere conducted on the Rosemount 405C and 1595 Conditioning Orifice Plateprimary elements. Extensive testing was also performed to determineminimum straight run requirements after the following upstream fittings; singleelbow, double elbows in plane, double elbows out of plane, reduction,expansion, and butterfly valve. Performance was also evaluated with up to 20degrees of swirl induced.Every Rosemount 405C and 1595 Conditioning Orifice Plate primary elementis flow calibrated as part of the manufacturing process. A calibration report foreither a 3 point (option code WC) or 10 point (option code WD) calibration canbe provided for shipment with the product.Independent TestingRosemount 405 and 1595 primary flow element models were tested at threeindependent laboratories: Colorado Engineering Experiment Station, Inc. (CEESI) Southwest Research Institute (SwRI) Foxboro Co. Flow Lab Daniel Flow LabCertified flow-data sheets were supplied from each of these facilities.Representative samples of tests conducted at Rosemount and independentlaboratories are in Section 3: Test Facilities and Flow Tests.1-2

Reference Manual00821-0100-4810, Rev BCMarch 2006PRODUCTSPECIFICATIONS405 and 1595The above testing has enabled Rosemount to provide product whichconforms to the following specifications:TABLE 1. Rosemount 405 Compact Orifice FlowmeterTypeBetaDischarge Coefficient UncertaintyConditioningConditioningStandard (1/2 to 11/2-in. line size)(1)Standard (1/2 to 11/2-in. line size)(1)Standard (2 to 8-in. line size)Standard (2 to 8-in. line size)0.40.650.40.650.40.65 0.50% 0.75% 1.75% 1.75% 1.25% 1.25%(1) Discharge Coefficient Uncertainty for 1/2-in. units with Beta 0.65 is 2.25% (2.5% of flow).TABLE 2. Rosemount 1595 Discharge Coefficient UncertaintyBeta RatioAccuracyβ 0.40β 0.650.50%0.75%Straight Pipe RequirementUse the appropriate lengths of straight pipe upstream and downstream of the 405 to minimize theeffects of moderate flow disturbances in the pipe. Table 1-1 and Table lists recommendedlengths of straight pipe per ISO 5167.Table 1-1. 405C / 1595 StraightPipe Requirements(1)Upstream (inlet)side of primaryBetaReducer (1 line size)Single 90 bend or teeTwo or more 90 bends in the same planeTwo or more 90 bends in different planeUp to 10 of swirlButterfly valve (75% open)Downstream (outlet) side of 46028187(1)(2)(3)BetaUpstream (inlet)side of primaryTable 1-2. 405P Straight PipeRequirements0.40ReducerSingle 90 bend or teeTwo or more 90 bends in the same planeTwo or more 90 bends in different planeExpanderBall / Gate valve fully openDownstream (outlet) side of primary(1) Consult an Emerson Process Management representative if disturbance is not listed.(2) Recommended lengths represented in pipe diameters per ISO 5167.(3) Refer to ISO 5167 for recommended lengths when using flow straighteners.1-3

Reference Manual405 and 15951-400821-0100-4810, Rev BCMarch 2006

Reference Manual00821-0100-4810, Rev BCMarch 2006Section 2405 and 1595Theory of OperationOverview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-1Technical Detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-1Compact Orifice Plate Technology . . . . . . . . . . . . . . . . . . page 2-2Conditioning Orifice Plate Technology . . . . . . . . . . . . . . . page 2-2OVERVIEWThe Rosemount 405 and 1595, based on orifice plate technology, is a deviceused to measure the flow of a liquid, gas, or steam fluid that flows through apipe. It enables flow measurement by creating a differential pressure (DP)that is proportional to the square of the velocity of the fluid in the pipe, inaccordance with Bernoulli's theorem. This DP is measured and converted intoa flow rate using a secondary device, such as a DP pressure transmitter.The flow is related to DP through the following relationship.Equation 1Q K DPwhere:Q Flow rateK Units conversion factor, discharge coefficient, and other factorsDP Differential pressureFor a more complete discussion on the flow equation, refer to Section 4: FlowCalculations.TECHNICAL DETAILAs stated previously, traditional orifice plate flowmeters are based onBernoulli's theorem, which states that along any one streamline in a movingfluid, the total energy per unit mass is constant, being made up of the potentialenergy (the pressure energy), and the kinetic energy of the fluid. Where:1 21 2P 1 --- ρV 1 P 2 --- ρV 222where:P1 Upstream pressureP2 Downstream pressurep DensityV1 Upstream velocityV2 Downstream velocityWhen fluid passes through the orifice the velocity of the fluid through theorifice increases. This increase in fluid velocity causes the kinetic energy ofthe fluid immediately downstream of the orifice plate to increase, whilesimultaneously decreasing the static pressure energy of the fluid at that samepoint. By sensing the static pressure on the upstream and downstream sidesof the orifice plate, the fluid velocity can be determined.www.rosemount.com

Reference Manual00821-0100-4810, Rev BCMarch 2006405 and 1595Some assumptions were made in deriving the theoretical equation, which inpractice are not valid: a) Energy is conserved in the flow stream. b) Pressuretaps are at ideal locations. c) Velocity profile is flat. These items are correctedby the discharge coefficient. Which is derived from experimental data and isdifferent for each primary element.Actual FlowDischarge Coefficient C Theoretical FlowCOMPACT ORIFICEPLATE TECHNOLOGYThe 405P Compact Orifice Plate is a wafer style meter and has a traditionalstyle orifice plate integrally machined into the wafer. The wafer is 1 inch thick.Meter inlet and outlet sections in this wafer are sized for schedule 40 pipe. Ifthe meter is installed in pipe where the schedule is something other thanschedule 40, adjustments are made in the flow calculations to accommodatethe pipe schedule mismatch. For more information on this please refer to“Thermal Expansion Corrections” on page 4-5.Orifice plates work well when the velocity profile is symmetrical about thelongitudinal axis of the pipe in which the fluid is flowing. In such cases, wherethe flow is conditioned or there is an adequate amount of straight run, thehighest velocity fluid is along the central axis of the pipe, coaxial with theorifice of the conditioning plate. This is the situation under which thedischarge coefficient was determined and is how most standard orifice platesare used. However, if an orifice plate is installed immediately after anupstream fitting the velocity profile will