Chun-Min Su, Win-Ti Lin, Sutham Masri
To verify the measurement capability and performance of the newly established primary low-pressure gas flow standard, a mercury-sealed piston prover, at the National Institute of Metrology of Thailand (NIMT), a bilateral comparison with the piston prover at the Center for Measurement Standards (CMS, Taiwan) was conducted. The piston prover at NIMT has a measurement capability of 5 mL/min to 24 L/min flow range with a relative expanded uncertainty smaller than 0.13 %, whereas that of the system at CMS is 2 mL/min to 24 L/min with 0.10 % expanded uncertainty. The transfer standard (TS) used...
Sutham Masri, Win-Ti Lin , Chun-Min Su
To establish the traceability chain of low-pressure gas flow measurement within Thailand, a primary standard with the capacity of 0.005 L/min to 24 L/min (at 296.15 K and 101.325 kPa) was established at National Institute of Metrology (Thailand); NIMT. The standard facility is a mercury-sealed piston prover consisting of three precision- machined glass cylinders. With the positive displacement technique, the facility measures gas flowrate by determining the displaced volume, time, and pressure and temperature of the gas. Flow measurement can be carried out manually or semi-automatically. The...
Jerker Delsing, Kristoffer Karlsson
Low-pressure gas measurements are of increasing interest in the process industry for both control purposes and emission measurements. Industrial measurement environments include some very challenging components, such as: • Dust, particles, vapor, water droplets, etc. • Temperatures up to 1200 °C • Pipe diameters of 1 to 10 m Ultrasound flow measurement techniques have many advantages for such industrial measurement problems. Currently, a major problem is the lack of transducer technology that is sufficiently robust to operate in the presence of the above given industrial components. For the...
Carlos Eduardo Jeronymo, Valter Yoshihiko Aibe
This work presents an electronic circuit for quadruple-timing pulse interpolation applied to compact piston provers. Compact provers are usually employed to prove meters with pulsed outputs. API and ISO standards recommend a minimum of 10000 pulses per run to obtain a resolution better than ±0.01 %. Since the volume of fluid displaced by a compact prover is relatively small, the number of pulses produced during a proving run is often considerably less than 10000 pulses. Pulse interpolation techniques are commonly used to increase resolution and to diminish uncertainty during a proving run by...
Michael Reader-Harris, Neil Barton, David Hodges
Orifice plates can be contaminated by oil, grease, pipeline sludge or other liquids or solids. Experience shows that sometimes the contamination extends to the sharp edge of the orifice plate, but that on many occasions any possible contamination near the edge is cleaned by the flow. The latter case is investigated here. In some of the existing sets of data the contamination in the form of soft deposits used to gather the data means that interpretation is not straightforward; so Computational Fluid Dynamics (CFD) was used to assist in the interpretation. In the experimental work the...
Richard Steven, Charlie Britton, Joshua Kinney
Cone DP meters are often used for unprocessed natural gas flow metering applications. Unprocessed natural gas flows can have entrained water and light hydrocarbon liquids. Hence, it is important to fully understand the wet gas flow response of cone DP meters. One method of metering the gas flow rate of a wet natural gas flow is to estimate the liquid flow rate (usually a mixture of hydrocarbon liquid and water) from an independent source (such as a tracer dilution technique or test separator histories) and then use a wet gas correction factor or "correlation" to correct for the liquid...
R. Mascomani , S. Saseendran, BVSSS Prasad
It is often difficult to realize calibrated accuracy of a flow metering system over measurement range when it is installed under hostile and perturbed flow conditions. Though widespread studies are reported in literature on individual characteristics of meters, comparative evaluation of the performance of these devices under real life installation situations is relatively inadequate. Present study compares classical venturi, cone, standard orifice and new slotted orifice and four hole orifice meters. Experiments are carried out to investigate the effects of single elbow, double elbow in and...
Casey Hodges, Charles Britton, William Johansen, Richard Steven
Cone DP flow meters are becoming increasingly popular for natural gas flow metering. A cond DP meter operates according to the same physical principles as other DP meters but it is not as yet included in the ISO 5167 report on DP meters. In this paper, thirty one cone DP meter single phase data sets from CEESI independent research, a wet gas research Joint Industry Project, and multiple third party cone DP meter calibrations are reviewed. The meters discussed have diameters ranging from 2” to 14”, beta ratios ranging from 0.45 to 0.85, Reynolds numbers ranging between 5e4 and 5e6, and...
Casey Hodges
There are several relatively new differential producing meters that are available for end users. Each meter claims to have advantages over other meter types, specifically orifice meters. Meter types discussed include; cone meters, Venturi meters, multi-ported averaging pitot tubes, multi-holed orifice plates, and diagnostic differential meters. This paper is intended to be used by purchasers of these meters to help them obtain the best meter for their application. The operating principles of these meters will be explored. This paper will look at the claims that the manufacturers of these...
Lei Sui, Toan H. Nguyen, James E. Matson, Peter Espina, IvanTew
Flare gas ultrasonic flow measurement has now been well established with more than 3000 units installed worldwide in process plants and refineries. One of the remaining technical challenges in flare gas ultrasonic flowmetering is to deal with extremely high flare flows (greater than 80 m/s) during emergency flaring. High flare flows introduce soaring flow noise, cause ultrasonic beam drift and thus deteriorate ultrasonic signal quality, leading to an ultimate failure of the flare gas flow measurement. In this paper, the ultrasonic propagation in flare gas has been studied, the beam drift due...