Home>API standards>API MPMS 22.4 2018 pdf free download

API MPMS 22.4 2018 pdf free download

API MPMS 22.4 2018 pdf free download.Manual of Petroleum Measurement Standards, Chapter 22.4 Testing Protocol for Pressure, Differential Pressure, and Temperature Measuring Devices.
3.6 Linearity The degree to which a response function describing the input-output relationship between a measured quantity and the signal produced by the measuring device can be described by a straight line. 3.7 Rangeability The capability of a measuring device to measure between a minimum and maximum input within an acceptable tolerance. Rangeability is generally expressed as the ratio of the maximum to the minimum. 3.8 Repeatability Measure of the agreement between the results of successive measurements of the same variable carried out by the same method, with the same instrument, at the same location, and within a short period of time. 3.9 Uncertainty (of measurement) The amount by which an observed or calculated value may depart from the true value. 3.10 Zero Measurand Output Zero The signal of a sensor with zero measurand applied. 3.11 Slope The ratio of the output signal to the measured variable between the zero value and the span value of a transmitter. Field of Application The field of application for this testing protocol is limited to devices that are used in the measurement of hydrocarbon fluids in the petroleum, energy, and petrochemical industries. Parameter Variations Affecting Device Performance 5.1 API 22.4 Baseline Tests In order to identify the performance changes resulting from changes in the operating condition, the baseline test is required, see 6.4. The following measures of performance are calculated from the baseline test: — Accuracy — Linearity — Repeatability — Hysteresis
5.2 Influence Testing Influence testing quantifies the environmental effect and the dynamic performance of pressure, differential pressure, and temperature measuring devices including: — Ambient Operating Temperature Influence — Pressure Operating Influence on Differential Pressure Transmitter Maximum Pressure/Differential Pressure Testing — Pressure Maximum Operating Pressure for Pressure Transmitter — Pressure Maximum Operating Pressure for Differential Pressure Transmitter — Differential Pressure Maximum Operating Differential Pressure for Differential Pressure Transmitter 5.3 Special Testing Special testing quantifies the effect of external mechanical and electrical conditions that may affect the performance of pressure, differential pressure, and temperature measuring devices. These tests are covered in 6.6. Tests The following sections describe API 22.4 testing requirements for pressure, differential pressure, and temperature transmitters. Test applicability is indicated in the test name and in Table 1.
6.1 Test Conditions Written testing procedures should be developed and agreed to by the party requesting the test and the test facility prior to the start of any testing. The sequence of tests should be considered and any tests that can alter device performance should be completed last. All deviations from written procedures or standards shall be documented. Care should be taken to ensure that influence factors not being tested are held as constant as possible to minimize their effect on the test results. Influence parameters shall be maintained per IEC 60770-2, Section 5.1. The major influence factors are ambient temperature, pressure, and humidity. Care should also be taken to eliminate or minimize the factors listed in 6.6. The average operating value and range of temperature, relative humidity and atmospheric pressure of the tests shall be measured and reported.
The transmitter shall be preconditioned by: a) Placing the transmitter in the environment and under the conditions it will be tested (e.g. with the covers removed) for at least 24 hours. b) Powering up the transmitter for at least one hour prior to testing. c) Cycling the transmitter (differential and pressure transmitters only) over the range it will be tested as specified in 6.4.1, a minimum of three times. d) Adjusting the transmitter by (differential and pressure transmitters only): 1) Adjusting the zero of the transmitter. 2) Adjusting the slope trim per Annex D if the device has not been factory calibrated. For a bi-directional differential pressure transmitter, each direction shall be treated as a separate device for the purposes of this testing. The transmitter filters and damping adjustments shall be set for minimum effect per manufacturers’ recommendation. Tapping of the transmitter during testing or evaluation is not allowed and the transmitter installation shall minimize the transfer of vibrations and mechanical shock. It is important to use measured atmospheric pressure when testing gauge pressure transmitters with absolute pressure reference standards. Changes in weather can cause atmospheric pressure differences up to ±0.5 psi (3.45 kPa) which at a 10 psia (68.95 kPa) operating pressure could result up to a 5 % error if an assumed atmospheric pressure is used.

Related PowerPoint Templates

Template Categories
Popular Tags