The Full Bore Flowmeter
Authors: Leach B.C. , Jameson J.B. , Smolen J.J. , Nicolas Y. 
Published: December 2007

Leach, B.C., Member SPE-AIME, Schlumberger Well Services, Houston, Texas Jameson, J.B., Member SPE-AIME, Schlumberger Well Services, Denver, Colorado Smolen, J.J., Member SPE-AIME, Schlumberger Well Services, Houston, Texas Nicolas, Y., Etudes et Production Schlumberger, Clamart, France
American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.
This paper was prepared for the 49th Annual Fall Meeting of the Society of Petroleum Engineers of AIME, to be held in Houston, Texas, Oct. 6–9, 1974. Permission to copy is restricted to an abstract of not more than 300 words. illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made. provided agreement to give proper credit is made. Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussions may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
The Fall Bore Flowmeter is a spinner-type velocimeter designed to be lowered through production tubing in order to measure flow rates in the casing below. The tool provides continuous fluid-velocity measurements at lower production rates than was possible with earlier Continuous Flowmeter equipment. possible with earlier Continuous Flowmeter equipment. In polyphasic flow it provides measurements that are more accurate and less affected by fluid-viscosity changes than those from the earlier Continuous Flowmeter.
The tool has a 1 11/16-in. diameter. The spinner-and-protective-cage assembly is run in the hole while collapsed to the 1 11/16-in. size. When the tool is below the tubing, it opens and the spinner blades are exposed to a large cross section of the flow in the casing. A considerably larger position of the total well production is metered through the spinner section production is metered through the spinner section than with the Continuous Flowmeter tool. The fullbore exposure of the spinner increases its sensitivity for use in low flow rates, and decreases the effect of changes in viscosity in polyphasic flow. The spinner suspension system has been designed to minimize the effects of friction. The tool is collapsed as it is pulled back into the tubing, and is held in the collapsed position while being retrieved to the surface. position while being retrieved to the surface. The Full Bore Flowmeter may be run by itself or in combination with the Gradiomanometer, Thermometer, Manometer, and thru-tubing Caliper. A Casing-Collar Locator run in combination with the Flowmeter provides positive depth control. provides positive depth control. Several field examples are presented showing downhole flow profiles and production profiles where problems exist, such as crossflow, plugged perforations, problems exist, such as crossflow, plugged perforations, and changes in contributions to production.