Tracerco pig tracking systems provide fast, reliable, effective and accurate tracking and detection of subsea pigs. Our proven pig tracking system means an operator will know exactly where a pig is during an inspection or cleaning activities as well as the speed of the pig. The operator can use this data to minimise the risk of damage and maximise throughput. In addition, rapid pig detection ensures that time is saved in locating any lost or stuck pigs preventing any significant financial losses for pipeline operators. Stuck pigs with no tracking device attached can also be located with Tracerco Explorer.
Pre-Commissioning/commissioning
Inspection
Operational
Maintenance and Repair
Abandonment
Decommissioning
Established to provide 100% accurate, safe and reliable pipeline pig tracking, Tracerco’s pig tracking systems can provide fast, effective and complete control of subsea pig tracking, positioning and location and is applicable to any line diameter and wall thickness, including pipe-in-pipe.
As a world leading innovator of specialist detection systems, Tracerco has made a number of strategic improvements to enhance its reliability, lifetime and versatility so that we can provide an even better service to our customers and users.
Our tracking systems ensure real time data collection and optimized use of ROV’s and divers. With proven reliability, our pig tracking systems can be deployed throughout the full life cycle of a pipeline. Accurate pig tracking is necessary from pre-commissioning through operational requirements to de-commissioning. During activities such as tool isolation and positioning (accurate to +/- 5cm), flooding, cleaning, gauging or dewatering, inline or MFL inspection in steel, rigid or pipe in pipe systems or within buried pipelines you can be secure in the knowledge the location of the pig or tool is known. Accurate and reliable pig tracking can also be applied to foam pigs as part of a pipeline cleaning testing run.
Case studies
By Chris Schendel—Offshore Project Manage—Americas
Tracerco’s GammaTrac system monitors and tracks pigging movements allowing for a successful maintenance operation.
Tracerco has completed many searches for missing or lost pigs including monitoring their locations in challenging environments such as the Arctic Circle and in the deep waters of the Gulf of Mexico.
The ultimate objective of every pig run is to complete the required task and return the pipeline to its original operating condition in the shortest time possible. A stuck pig could cause delays resulting in higher project costs so it is important to have a contingency plan should the pipeline pig become stuck to be able to monitor the effectiveness of the inspection campaign.
Tracerco’s GammaTrac was developed as a reliable method of tracking pigs through pipeline systems. Implementing GammaTrac into your inspection campaign is a reliable and simple operation that has a proven track record in the industry. The unit can operate on any diameter pipeline including pipe-in-pipe, topside or subsea, with the ability to be used for gas, liquid or multi-walled pipelines.
GammaTracs are deployed either by divers or ROVs to the designated monitoring locations. They have four unique functions built into the firmware. These operating functions include Flagger, Ranger, Totalizer and Interrogator:
Flagger—single pigging operation that exhibits one trip visualization on the LED screen.
Ranger—works as a radiation intensity meter to pinpoint the location of a pig based on the strength of the isotope installed.
Totalizer—counts the total number of tagged pigs that have passed the monitoring location.
Interrogator-combines all of the modes and counts the total number of pigs and time of passage.
When an isotope-tagged pig passes a specific location the GammaTrac unit records the date and time of the event. The event is stored internally and displays the time and number of pigs that have passed externally on an LED screen. This feature of the unit, known as “Interrogator”, (Figure 2) is the most widely used feature due to its versatility and ability to download the stored data from the internal memory. The battery life is rated at 3000 hours which eliminates the need for constant battery changes and prolongs the deployment time subsea.
Large Scale Tracerco Diagnostics Pig Tracking Project in the GOM.
Tracerco was requested by a GOM operator to supply pig tracking isotopes and equipment for use on the dewatering, conditioning and commissioning phases of a newly installed 200+mile pipeline.
Tracerco GammaTrac and ROV alarm equipment was allocated for the project to track the pig launch/receipt times. The Tracerco ROV Alarm equipment consists of a subsea radiation detector that is integrated through the ROV, to provide results in real-time to a topside laptop computer. Two Tracerco technicians and the full equipment spread were mobilized and deployed to three marine support vessels (MSVs). Isotopes were loaded into the initial 3 pigs for the dewatering phase and introduced into the pipeline.
Dewatering Project Phase One
During the planning stages of the project, the pipeline operator agreed to utilize seven GammaTrac units at discrete locations subsea. After the project started the plan was revised to use four of the seven units for monitoring. Pumping began and it was calculated to take around.
14 days to clear the water from the pipeline. The pipeline differential pressure and discharge on the platform end were monitored by Tracerco during this 14 day span. It was assumed that the pigs were progressing as expected by monitoring these conditions.
An investigation started at the platform end of the pipeline due to the pressure drop and water returns that were observed. One of the pigs sustained slight damage during the launch operations and stalled in the pipeline. The stalled pig was bypassing in the pipeline unbeknownst to the pumping crew and operator. Tracerco technicians utilized the ROV Alarm equipment to locate the pig starting at the last known GammaTrac location in the pipeline. The pig was located by the ROV Alarm detector approximately 75 miles away from where the operator expected.
If the original plan to strategically place the seven GammaTrac units subsea was put in place, the operator could possibly have eliminated 7-10 days of vessel and man time by monitoring a larger area of the pipeline which would have saved a substantial amount of money on the overall project cost. When placed at dedicated intervals along the pipeline, the GammaTrac units work as visual markers to show the pigs’ progression to the platform destination.
The GammaTrac LED display is easily visible subsea via the cameras on the ROV. The stuck pig finally stopped bypassing after a regimen of pressure pulsing and pipeline bleed-off operations. The pigs were then tracked through the final 75 miles of pipeline utilizing the ROV Alarm detector equipment to the parking location specified by the operator to complete the first phase of the dewatering operations.
Conditioning Project Phase Two
The Phase two of the pigging operations began approximately a month later after the process piping was aligned and tested for the jumper tie-in to the platform. Another series of tagged pigs were introduced into the pipeline for tracking purposes. For this phase, twelve additional GammaTrac units were mobilized to be deployed subsea for the pig tracking operations. The monitoring positions for the units were placed at each of the six In-Line Skids (ILS) and In-Line Valves (ILV). With this amount of equipment deployed subsea, the pipeline monitoring coverage was divided into 20 segments which enabled the ROV equipped vessels to track the progression of the pigs through the pipeline during the conditioning phase.
A total of seven pigs were tagged and introduced into the pipeline. The MSVs utilized the Tracerco ROV Alarm equipment to track the pigs down the length of the pipeline. Utilizing the Interrogator function the total number of pigs were counted and their time of passage was logged for each of the seven pigs passing through all of the monitoring locations. The calculated pigging time for this phase was soon adjusted after the pig velocities were shown to be travelling slower than expected due to the change in bathymetry of the sea floor, displacement of sea water, the pipeline conditioning chemicals and nitrogen. The positioning of the GammaTrac units allowed operations to stay immediately up to date with accurate time stamps for each pig at each location. The pig passage times were relayed throughout the customer operations team in order to modify pumping rates and the chemical injection process.
The primary tracking vessel continued to follow the pig train down the length of the pipeline to the termination platform where the Tracerco technicians removed the radioisotopes during the pig recovery operations. A secondary vessel was utilized to recover the GammaTracT”‘ array and perform the necessary valve alignments for the pipeline
shut-in procedure.
Conclusion
With the implementation of the Tracerco Diagnostics Pig Tracking services our customer was able to use the monitoring information obtained to accurately track/time the pig train’s progression down the length of the pipeline which resulted in a savings of vessel and equipment costs, and enabled the customer to accurately apply the necessary procedures to complete the project.
The development of the Tracerco GammaTrac is a field proven technology for over 20 years providing our customers with rapid and reliable results. This technology is utilized by various operators on a regular basis to provide accurate tracking of pigs introduced into subsea pipelines.
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