Abstract: An improved apparatus and method for gravel packing is provided. The apparatus includes a substantially tubular-shaped base pipe having a plurality of apertures disposed along part of its length and a dual-wall sand screen coaxially secured to the base pipe. The dual-wall screen is substantially permeable to fluids and impermeable to sand. The apparatus provides a plurality of fluid permeable channels formed within the sand screen, which are disposed along the entire length of the screen. Each channel has an associated plurality of ports spaced along discrete intervals of the screen, which communicate with an annulus formed between the apparatus and the wellbore. The method provides for injecting a sand and fluid slurry mixture through the screen and out of the ports. This design reduces the incidence of sand bridge formation, and packs gravel around any sand bridges, which may be formed.

Abstract: An improved apparatus and method for gravel packing is provided. The apparatus includes a substantially tubular-shaped base pipe having a plurality of apertures disposed along part of its length and a dual-wall sand screen coaxially secured to the base pipe. The dual-wall screen is substantially permeable to fluids and impermeable to sand. The apparatus provides a plurality of fluid permeable channels formed within the sand screen, which are disposed along the entire length of the screen. Each channel has an associated plurality of ports spaced along discrete intervals of the screen, which communicate with an annulus formed between the apparatus and the wellbore. The method provides for injecting a sand and fluid slurry mixture through the screen and out of the ports. This design reduces the incidence of sand bridge formation, and packs gravel around any sand bridges, which may be formed.

Abstract: The pressure of a heated fluid is reduced in a test chamber. A small vent in the upper portion of the test chamber receives a stream of liquid from the chamber and yields a steady hiss when the fluid in the test chamber is under sufficient pressure to maintain the fluid solely in the liquid phase and it yields a sputtering hiss sound when the pressure in the test chamber is reduced sufficiently to permit steam and/or gases to coexist with the liquid in the chamber thus permitting liquid plus vapor to enter the vent. The change in sound may be used to alert an operator and/or pressure fluctuations in the test chamber may be automatically monitored to produce an output signal or a feedback signal for automatic control.