Papers

Gas chromatography is one of the most widely used techniques for analyzing hydrocarbon mixtures. Some of the advantages of chromatography are the range of measurement (from ppm levels up to 100%), the detection of a wide range of components, and the repeatability of the measurements. Chromatography is used in the laboratory, in permanently installed online …

FUNDAMENTALS OF GAS CHROMATOGRAPHY Read More »

Much effort is spent to achieve accurate measurement. Up to date measurement standards, modern meter station design, high quality equipment, and proper measurement operations are all necessary for measurement accuracy. Unfortunately, these processes do not assure measurement accuracy if the contract does not also support accurate measurement. The contract impacts measurement accuracy by what it addresses and what is left unaddressed. More focus needs to be applied to the measurement sections of the contracts. Hopefully this paper will help the reader better understand the relationship between the contract and accuracy.

This paper presents fundamental information necessary to understand and appreciate the concept of total gas energy in a natural gas pipeline. That is, to be able to converse with peers within the natural gas industry and understand basic concepts and terminology. Discussed is the historical transition from volumetric measurement to total gas energy including some …

FUNDAMENTALS OF ENERGY DETERMINATION Read More »

Electronic flow measurement as applied to the natural gas industry has advanced considerably over the last 30 years. Applications to address Upstream, Midstream and Downstream gas measurement technologies have become more complex. Over time it has become necessary to understand the fundaments that make up this ever-changing environment. This paper will discuss the important fundamental …

FUNDAMENTALS OF ELECTRONIC FLOW METER DESIGN, APPLICATION & IMPLEMENTATION Read More »

Fundamental to all electronic gas measurement (EGM) and electronic liquids measurement (ELM) systems is the ability to accurately measure, review, correct, and report data. Any weakness in this chain undermines the accuracy and data integrity in the system.

Recent industry standards and practices have greatly expanded the emphasis on data integrity. The Sarbanes-Oxley (SOX) Act of 2002 focuses on the integrity and consistency of all financial-based transactions for an organization.

A SOX auditor will directly reference the American Petroleum Institute (API) Manual of Petroleum Measurement Standards (MPMS) Chapter 21 (popularly known as “API 21”) as the standard for all steps in the measurement process throughout an organization. Therefore, measurement personnel must possess a thorough understanding of API 21 and put its requirements to practice in order to satisfy the audit process.

The first gas company in the U.S., The Gas Light Company of Baltimore, Maryland, founded in 1816, struggled for years with financial and technical problems while operating on a “flat rate” basis. Its growth was slow with the charge for gas service beyond the pocketbook of the majority. By comparison, the New York Gas Light …

FUNDAMENTAL PRINCIPLES OF DIAPHRAGM DISPLACEMENT METERS Read More »

Since the early 1980s, Coriolis meters have gained worldwide acceptance in gas, liquid, and slurry applications with an installed base of more than one million units. Through significant design, enhancements in the early 1990s Coriolis meters have rapidly gained worldwide acceptance in gas phase applications with over 100,000 meters installed worldwide and most notably the …

FUNDAMENTALS OF CORIOLIS METERS AGA REPORT NO. 11 Read More »

Meter inspections, configuration changes, calibration verification, troubleshooting, and gas sampling generate important subsets of measurement data. Automated computer systems capture, process, store, and report this data better than manual, paper-based systems; minimizing effort, time, resources, and error for field and office workers.

Measurements of pressure and temperature are made for many reasons and by several methods. This paper will focus on measurements made during gas production and transportation and suggests criteria to be used in the selection and installation of the instruments used to measure these physical properties. In this industry, pressure and temperature measurements are primarily …

Basics of Ascertaining Effective Pressure and Temperature Measurement Read More »

Electronic gas measurement auditing or EFM auditing is a very important process in the natural gas industry. Within the last twenty years, the natural gas industry has changed from the dry flow chart recorder to the Electronic flow Computer(EFM) as the primary method of recording the measurement data for custody transfer.
These flow computers are still typically connected to an orifice meter and are subject to all of the problems in the primary device that a chart recorder was. In addition they have their own set of problems that crop up in the flow computer and transmitters, some of which had similar problems when it was a chart recorder and some of which are unique to the flow computer. Careful review of the meter data should still be (and usually is) a part of the monthly close process. Even with the review process, occasionally measurement errors make it through to the payment calculation. It is for this reason that auditing is necessary and prudent. A proper audit procedure can be cost effective and ensure that proper credit is received for any delivery. As a side benefit, it will also help ensure that internal measurement is being performed properly.