Offshore drillers often use a single pipeline to carry a mix of liquid hydrocarbons, gas, and water from satellite wells to a central production platform.

Using a single pipeline is cheaper, but the flow of liquid and gas can cause problems. The gas flows faster than the liquid. Liquid tends to accumulate in the dips and inclined pipe sections. From time to time, large volumes of liquid, known as slugs, build up in the pipeline.

Among the problems that slugs create is suppression of the pipeline flow. Gas trapped behind a slug moves slower through a pipeline than it would if the way were clear. Pressure builds behind a liquid slug to keep it moving. Sometimes there is a hard-to-control surge of compressed gas when it finally reaches the pipeline's outlet.

Shell Global Solutions' S3 controls liquid slugs that can cause surges in pipeline and riser systems.

One method of avoiding this problem is to store the liquid concentrations temporarily in vessels known as slug catchers, and then release the liquids in a controlled manner for further processing. However, this is costly, according to Konstantin Kovalev, who handles slug mitigation for Amsterdam-based Shell Global Solutions. Shell developed an alternative approach, known as the Slug Suppression System, or S3, to address the problem. Shell has since licensed the system to Dril-Quip of Houston, for manufacturing and sales.

The S3 system consists of a small vessel called a miniseparator, which has two outlets, one for gas flow and the other for liquid flow. The mini- separator is positioned between the top of the riser that brings the oil and gas topside, and the first-stage separator that separates the liquid and gas. The flows of gas and liquid are controlled by fast-acting valves, which receive their signals from a FieldPoint 2010 control system, from National Instruments of Austin, Texas. Shell developed algorithms for the application using National Instruments' LabVIEW software.

Shell tested the S3 system on an air-water loop with 100 meters of pipeline and a 15-meter riser. The complete measurement and control system was developed on this loop. After the initial tests, the system was evaluated successfully under field conditions on the Shell U.K. E&P Gannet-Alpha platform in the central North Sea. Kovalev said the system is applicable to both on-shore and offshore drilling operations.

Whatever method of inspecting labels a packaging line uses, it has to be done fast and done right. People must be able to read what's in the can, and the cans have to look good in the store. Labels have to make it onto the right containers, too, of course. After all, nobody wants to open the chicken noodle soup and find creamed corn inside.

Care Controls Inc. of Mill Creek, Wash., has introduced a roll-through system that will not only catch cans with labels missing, but will also spot the improperly glued labels—the flappers and dog-ears—and other imperfections. The unit inspects labels at a rate of up to 1,200 pieces per minute. Cans with labels that don't pass muster are automatically taken out of the line.

The Canalyzer RTLI label inspector makes sure that cans are properly labeled before shipping.

The basic Canalyzer RTLI unit uses a color sensor that checks for the condition of the label. The sensor is set to the color of the can. If a can missing a label rolls by, the sensor reads the metallic color, triggering the reject mechanism. At the same time, the cans roll past a laser beam. A loose or dog-eared label will break the beam, also flagging it for rejection.

An option is available to make sure that the labels match the contents in the can. Cans are often stored in warehouses for many months without labels, according to Greg Osenbach, an engineer in product development at Care Controls. An optical character recognition module can read a code printed on the can as it rolls by and a bar code reader confirms that the
label matches.

Osenback said the reject mechanism pinpoints cans moving at high speeds in close proximity to each other. The cans roll on their sides along a track. A mechanism removes cans by allowing rejects to fall through openings in the track, into a reject bin below. A rejected can is removed from the line without affecting the cans immediately in front of or behind it, and without slowing down or stopping the flow.

The basic unit handles standard can sizes from 202 to 603, and inspection systems can be configured to handle plastic or glass containers as well, said Osenbach.

Oil drilling contractors need a constant feed of information about operations they can't see.

A driller will look for hints by keeping tabs on the tanks known as mud pits, for instance. During a drilling operation, mud and water are pumped into the hole to help lubricate and clean the drill bit and to act as a coolant. Mud that is pumped out of the hole is circulated through a filter that removes cuttings and waste, after which the mud is sent into the pits to be recirculated down into the hole.

The driller measures variables of the mud—temperature, pH, and tank level—to determine conditions downhole. The level of the mud in the pits alerts the driller to possible changes. For example, a sudden increase of mud level might indicate that the drill hit a gas pocket, and pressure is pushing the mud back up the hole.

Wilcoxon Research's wireless transmitter and receiver reduced cable needed at a drilling site.

A potential weak link in the data flow is the transmission cable, which must be installed around obstacles and is exposed to anything harmful between the sensors on the job and the computer that collects the facts. M/D Totco, a unit of Houston-based Varco International, decided to get rid of some of that cabling. M/D Totco, which supplies instrumentation to drillers, installed a wireless transmitter as a field test at a site in east Texas.

M/D Totco replaced the signal cable between the level sensors at the mud pits with a BlueLynx BLM Bluetooth wireless transmitter supplied by Wilcoxon Research Inc. of Gaithersburg, Md. The BlueLynx unit provides connection for four 4-20-milliamp signals and has a range up to 300 feet, according to Wilcoxon. In the test setup, the level sensors were hard-wired to the wireless transmitter on the side of the tank. Signals were transmitted wirelessly to a receiver, which was wired to the data acquisition unit.

Sean Cuff, the M/D Totco field engineer who installed the wireless unit, said the system has performed well in a demanding environment. Temperatures ranged from freezing to 90°F over a three-month test period, and the transmitter operated in nearly 100 percent humidity at the mud pits, where it was subjected to steam and heat. Transmitter and receiver were placed about 50 feet apart and were not directly in line of sight, he said. The wireless installation saved about 100 feet of signal cable.

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