摘要:
A process is disclosed for assembling a gun tube for use in a perforating system. At a first location, which is not the site where perforating operations are to be conducted, the gun tube is completely assembled except for an initiating device. After transporting the gun tube to the site where perforating operations are to be conducted, an initiator is connected and installed via port in the gun tube.
摘要:
An apparatus string for use in a wellbore has a plurality of activation modules having first and second ends and containing devices to be activated/initiated downhole. An apparatus string also has a plurality of initiator modules where at least initiator is operatively connected to each activation module and is addressable. Each initiator module may have a safety initiator which when the initiator module is addressed initiates the firing of the shaped charges in the gun module to which it is operatively connected. A wireless transmitter is operatively connected in and integral to the apparatus string for use in transmitting signals to address any initiator module in the apparatus string.
摘要:
An apparatus string for use in a wellbore is disclosed comprising a plurality of activation modules having first and second ends and containing devices to be activated/initiated downhole. An apparatus string according to the present invention also comprises a plurality of initiator modules where at least initiator is operatively connected to each activation module and is addressable. Each initiator module may comprise a safety initiator which when the initiator module is addressed initiates the firing of the shaped charges in the gun module to which it is operatively connected. A wireless transmitter is provided which is operatively connected in and integral to the apparatus string for use in transmitting signals to address any initiator module in the apparatus string. An apparatus string according to the present invention may be especially useful in perforating operations.
摘要:
A telemetry system employs a periodic pseudorandom training sequence to effectively initialize an adaptive digital FIR filter-equalizer for optimal communications between a surface modem and downhole measuring equipment, without requiring any changes to the normal logging configuration or any special operator intervention. In a "training mode", an electronic source in a downhole sonde transmits a predetermined training sequence to a surface modem via a cable. The source preferably transmits the training sequence continuously until the surface modem has acclimated itself to the characteristics of the multiconductor cable by adaptively configuring the filter-equalizer, thereby enabling the surface modem to accurately interpret data received from the sonde despite attenuation, noise, or other distortion on the cable. The filter-equalizer adjusts itself in response to an error signal generated by comparing the filter-equalizer's output with a similar training sequence provided by a training generator. After the surface modem is trained, the system operates in an "operational mode," in which the sonde transmits data corresponding to downhole measurements, and the filter-equalizer's error signal is generated by comparing the filter-equalizer's output to a sliced version of the filter-equalizer's output. In this mode, the filter-equalizer continually adjusts itself to most accurately receive and interpret the data.
摘要:
A perforating gun that is usable with a well includes at least one perforating charge and a initiator. The initiator includes an explosive ballistic train to the perforating charge(s). The initiator is adapted to physically misalign components of the ballistic train to prevent inadvertent firing of the perforating charge(s) and physically realign the components to arm the ballistic train.
摘要:
The present invention provides for an apparatus and method of use to control a downhole tool remotely based on the autocorrelation of command sequences. Repeating signals of a priori unknown or undefined shape can be correlated to themselves to reliably distinguish intentional changes from random fluctuations or other operations performed on the well. Using autocorrelation, any fluctuation of pressure of sufficient amplitude can be used to send commands by controlling the timing or the number of repetitions of the sequence.
摘要:
The operation of hostile environment logging tools at temperatures up to 250.degree. C. stresses not only the tools, it also places severe demands upon the wireline telemetry due to the wide variations in the logging cable transmission characteristics. A robust adaptive wireline telemetry system for use in hostile environments has been developed that combines sophisticated digital communication methods with modern Digital-Signal-Processing (DSP) techniques. The downhole telemetry transmitter outputs a multilevel signal. The uphole receiver includes an adaptive transversal-filter equalizer (TFE) that is continually optimized to correct for changing signal distortion. The system operates robustly at high data rates over the temperature range of 0.degree. to 250.degree. C.
摘要:
An assembly for minimizing damaging effects of pressure waves on devices in a wellbore. The assembly comprises a dynamic device disposed in the wellbore and generating pressure waves during actuation; a barrier device disposed in the wellbore and presenting an obstacle to the pressure waves generated by the dynamic device; and an occlusion disposed in the wellbore between the dynamic device and the barrier device which reduces the damaging effects of the pressure waves on the barrier device.
摘要:
An assembly for minimizing damaging effects of pressure waves on devices in a wellbore. The assembly comprises a dynamic device disposed in the wellbore and generating pressure waves during actuation; a barrier device disposed in the wellbore and presenting an obstacle to the pressure waves generated by the dynamic device; and an occlusion disposed in the wellbore between the dynamic device and the barrier device which reduces the damaging effects of the pressure waves on the barrier device.
摘要:
A system for use in a wellbore includes plural modules for positioning in the wellbore and including respective interfaces, where the plural modules are configured to perform predefined downhole tasks in the wellbore. The plural modules are associated with respective local power sources. A telemetry subsystem enables communication between at least two of the plural modules, where the communication between the at least two of the plural modules allows one of the two modules to affect an operation of another of the two modules.