摘要:
A method of hydraulically fracturing a formation comprises controlling a pump rate during hydraulic fracturing of the first section of the horizontal well bore during a first period to break down the formation while reducing pick up of sand positioned in the well bore; during a subsequent second period to pick up the sand positioned in the well bore generally at a rate at which the formation will accept the sand; and, during a subsequent third period to fracture the formation.
摘要:
A disturbance locating system includes a voltage transducer, a current transducer and disturbance energy determination circuitry. The system may also include disturbance power determination circuitry. The voltage transducer couples to an output of a voltage transformer, the output of the voltage transformer representative of a voltage on a line. The current transducer couples to an output of a current transformer, the output of the current transformer representative of the current flowing through the line, the output having a forward reference direction and a behind reference direction. The disturbance energy determination circuitry couples to the voltage transducer and the current transducer. Based upon the inputs received, the disturbance energy determination circuitry determines disturbance energy flowing in the line and estimates a direction of disturbance energy flow with respect to the system as either in front of or behind of the disturbance locating system.
摘要:
There is disclosed a vibrating electric heating pad connected to a vibrator having a vibrating plate suspended in foam plastic in the vibrator housing and a control module with a slide switch and a transformer/rectifier. In a preferred embodiment, the vibrator is attached by velcro strips to the heating pad, and via a jack to the control module. The control module is also electrically connected to the heating pad and controls the heating pad and the vibrator.
摘要:
A dental plaque disclosing light for use in conjunction with a fluorescent dye plaque disclosing solution contained in a periodontal area of an individual's mouth is disclosed. A parabolic reflector supports a light source providing only light which causes the fluorescent dye to fluoresce. The light source is located in conjunction with the parabolic reflector to cause the parabolic reflector to project a solid, converging cone of light. Preferably, the light source is located forward of the focus of the parabolic reflector. A power supply is selectively connected to the light source for illuminating the light source. The power supply may be one or more batteries, and if the batteries are of the rechargeable type, a means for selectively recharging the batteries is connected to the batteries. A lens is supported adjacent the light source for projecting a solid, diverging cone of light having an axis concentric with the axis of the converging cone of light. A casing which supports the parabolic reflector also supports a reflecting surface adjacent the parabolic reflector such that, when the converging cone of light and diverging cone of light are directed toward the individual's mouth, the light reflected by the fluorescent dye is reflected by the reflecting surface and directed toward the individual's eyes. The light source may be a lamp and a filter means covering the lamp for filtering and passing therethrough only light which cuases the fluorescent dye to fluoresce.