API MPMS 5.1:2005(2011) pdf download
API MPMS 5.1:2005(2011) pdf download.Manual of Petroleum Measurement Standards Chapter 5- -Metering Section 1- -General Considerations for Measurement by Meters.
5.1.7.1.5 A back-pressure valve may he required to maintain the pressure on the meter and the prover above the fluid vapor pressure. In general. dispLacement meters do not acedcrate fluid velocity and are not normally subject to the resulting pressure reduction that can cau-se vaporitation (ca’ itationi in other types of meters.
5.1.7.2 PIPING INSTALLATION
5.1.7.2.1 Meters are normally installed in a horitontal position. The manufacturer shall be consulted if space lintitation.s dictate a different position. For example. Coriolis meters are somçtimçs installed vertically.
5.1.7.2.2 bere the flow range is too great fix any one meter. where shutting down the metering system is impractical. or where frequent service is needed, a hank of meters may he installed in parallel. Each meter in the hank shall he operated within its minimum and masimum flow rates, A means shall be provided to balance flow through each meter.
5.1.7.2.3 Meters should he installed and operated to have a maximum, dependable service life. This may require that protective devices be installed to remove from the liquid abrasives or other entrained substances which could stop the metering mechanism or cause premature wear. Strainers, filters, sediment traps, settling bnk., water separators. a combination of these items, or any other suitable devices, can he used. i’hey should be properly sited and installed to not adversely affect the operation of the meter or the overall systent. Protective devices tttay be installed singly or in an interchangeable battery. depending (in the importance of continuous service. Monitoring devices should he installed to determine when the peotectise device needs to be cleaned,
5.1.7.2.4 Meters shall be installed and operated to perform satisfactonly within the viscosity, pressure. temperature. and flow ranges that will be encountered.
5.1.7.2.5 Meters shall he adequately protected from pressure pulsations. from excessive flow surges and from excessive pressure caused by thennal expansion of the liquid. This kind of protection may require the installation of surge tanks, expansion chambers, pres.sure•limiting valves, relief valves, or other protective devices. When pressure relief valves an located between the meter and the provefl a means of detecting leakage from the valves shall he provided.
5.1.7.2.6 Any condition that contributes to the release of vapor from the liquid stream shall he avoided through suitable system design and through operation of the meter and prover within the flow range specified by the manufacturer.
If it is impractical to mount the temperature-measuring device in the meter. the des ice should be instalkd either inuncdiatcly downstream preferable. especially far turbine mctcrs) or upstream of the meter run. Where several meters are operated in parallel on a 4xwnmon stream. one tempera. ture-measuring device in the iota] streani. located sufficiently close to the mclcr inlets or outlets, is acceptable it the stream temperatures at each meter and at the sensing location agree within the tolerance specified in Chapter 7. Test thermosselks) should hc provided downstream ol’ each meter. or downstream of all the meter runs, to verify that the stream tempenifures are identical and the upstream temperature is representative of the temperature at the meters. Refer to API MP%f S Chapter 7 far additional information.
5.1.7.2.14 To determine meter pressure, a gauge. recorder. or transmitter of suitable range and accuracy shall be installed near the outlet of each meter run. Near the inlet is acceptable for displacement and Coriolis meters.
5.1.7.2.15 A heat-traced nsanift$d that maintains a heavy hydrocarbon in a sutYicientiy liquid state to permit measurement by a meter shall he designed to meet the following objectives:
a. An escessively high temperature (e.g.. esceeding equip. meni manubcturcrs masimum temperature specification), cannot occur
h. The temperature cannot rail below the level at which the viscosity of the liquid becomes too great for the meter at the required flow rates.
c. Temperature conIro is especially important ss hen the meter is not operating. The meter manufacturer should be consulted about high and low limits for viscosity and temperature.
