Examples from the Field

	Quantum Engineering Corporation

Interesting Examples from the Field

QEC staff have learned that most field tests have some unique feature that requires
an innovative adaptation. This page highlights some of these interesting cases.
It will be updated periodically.

Wells Using Wire-Wrapped Stainless Steel Screen.jpg (26055 bytes)

The Problem

A fully slotted screen is ideally suited to the flowmeter method for determining the vertical distribution of flow entering or leaving a well. It is relatively easy to seal the annulus between the outside of the probe and the pipe wall of a fully slotted screen. This prevents flow from bypassing the recording portion of the probe. However, it is virtually impossible to seal the region between the outside of the downhole probe and the walls of a wire-wrapped screen. These screens are constructed by wrapping wire around several vertical ribs extending over the length of the screen. The internal ribs preclude either an inflatable packer or collar from effecting a good seal.

The Solution

The flowmeter method is based on the relative flow rate entering the well from each geologic stratum. The data recorded by the flowmeter accurately represent the flow rate entering or leaving each stratum as long as the ratio of the flow bypassing the probe to the flow through the recording interior is constant.

Flow rates can be analyzed directly as recorded to estimate the hydraulic conductivity distribution, or adjusted to account for the bypass flow. Adjustments are made using flows measured at solid sections of the pipe. However, it is essential that data collected at the solid joints be recognized as inconsistent with data collected in the screened segments as shown below