Output from a flow analysis includes:
(a) Hydrostatic and friction pressure
gradients
(b) Velocity (of each phase present)
(c) Gas volume fraction/foam quality
and flow type for two phase flow
(d) Reynolds number
(e) Effective viscosity and shear rate
All of the above listed parameters are output at various measured depths between the wellhead and bottom of hole for both inside the coil and its annular.
CIRCA™ Tubing Force Analysis
The forces experienced by a workstring vary along its length according to a large number of variables, some of which are quantified by the circulation model, i.e.
• Fluid and gas densities (used in the calculation and buoyancy and gravitational forces)
• Hydrostatic and friction pressure gradients
Output from the tubing force analysis includes:
• Weight indicator gauge reading
• Weight indicator gauge reading at operating limits • Wellhead pressure
• String pressure
• String injection pressure • Friction force
• Tension force • Triaxial stress • Spiral pitch
• Collapse differential limits
All of the parameters output from CIRCA™ are available in report form or graph.
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CYCLE™ - COILED TUBING FATIGUE MANAGEMENT
The purpose of the CYCLE™ program is to accurately estimate the life span of coiled tubing strings based on fatigue, ballooning and corrosion. All of the activity that the coiled tubing has been exposed to is recorded in a string file. A mathematical model of fatigue determines the life expectancy of the coiled tubing. Accurate knowledge of tubing damage can prevent fatigue related coiled tubing failure.
The CYCLE™ program enables BJ Services operations to: • ability to provide real time on the job string history update
• compile a complete history of work string activities including jobs, runs, maintenance activities, and coiled tubing failures
• assess the service for which each existing string is currently fit based on fatigue, ballooning and corrosion calculations
• view graphs and reports that summarize the history of each string including the estimated fatigue and the safe working life remaining The information that is input
into CYCLE™ is stored in a string file. The string file provides a history of all the activity that the coiled tubing has been exposed to, from the date it was purchased until the date it is taken out of service. It also provides an assessment of the resultant tubing damage, including how much use of the string remains.
The fatigue and ballooning calculations used to determine tubing damage are based on the data provided by the string file. They are only as accurate as the data provided. String file data is critical to safe and efficient coiled tubing operations. Accurate knowledge of tubing damage can prevent fatigue and related coiled tubing failure.
CYCLE™ works in conjunction with another program called CYCLE DB™. The CYCLE DB™ program manages the information captured by CYCLE™.
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Monitoring Equipment
Monitoring, recording and control equipment is crucial to job performance. For this reason, BJ uses the most advanced instruments in the field to monitor job progress. Among them being:
Job Master
BJ Services provide a unique data acquisition system capable of recording, monitoring and displaying all necessary information during coiled tubing operations. The system is designed to interact with the coiled tubing well model and the cycle/fatigue life program to perform real time update during the job. In addition, the system is simple to maintain, interacts with all standard computing equipment and above all, is user friendly.
A Windows driven software program has been developed to ensure simplicity of operation and download of information. The unique display and keyboard allows our Engineers or Operators to interact with the system to change operating parameters if well conditions change. This provides an environment where decisions are taken that guarantee safety, maximize efficiency and ensure well integrity.
Information can be downloaded via a CD or large capacity 100 Mb zip disk and then printed out via a standard computer in the field or back in the office.
Wireless LAN
The BJ Services Wireless LAN System replaces well site LAN cabling with radio links allowing for zero time deployment at the wellsite of treatment data communication. The units directly replace BJ LAN cables or may be used interchangeable with LAN cables. Since cabling is not used, the problems with maintaining conventional cables are eliminated and the reliability of the signals are improved.
Features and Benefits
• Operates in extremely harsh environments with immunity from interference.
• Eliminates the need to run LAN cables between units and the time it takes to lay, retrieve, clean and store these cables.
• Supports wireless data transmission between 3305 and remote computers via the computer serial port.
Figure 53. Wireless LAN Figure 54. Wireless LAN Wireless Wellhead Unit
The Wireless Wellhead Unit provides complete monitoring capabilities at the wellhead without the need for cable’s running back to the control cabin. The Wireless Wellhead Unit is designed to operate with BJ's JobMaster system. The unit is approximately 5 1/2 feet high.
Power Center link for BJ monitoring & miscellaneous equipment:
https://powercenter.bjservices.com/__86256d48004debc5.nsf/WebByCatego ry?OpenView&Start=1&Count=30&Expand=1#1
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Health and Safety