The down-well environment is fraught with corrosive and mechanical challenges which are steadily increasing as reservoirs become increasingly sour, deeper and horizontal drilling becomes more common. Electromechanical cables (EMC) are used whenever services need to be performed during the entire life of the well. As soon as a well is drilled radioactive and sonic tools are lowered to reveal the lithography; this determines where the oil and gas is and whether the well will be economical to produce. Lowering and raising the tools and communicating with them requires an EMC cable. As it is raised the tool constantly emits a signal, sending information back to the operator to provide a map of the wellbore and the rock formations around it.
Mr. Dustin Dunning from Camesa explained to Stainless Steel World some of the challenges that these highly specialized cables must overcome. “Our cables provide the essential communication link between the tools and surface, and with that information the customer can decide whether to go ahead and complete the well,” explained Mr Dunning, who is Global Sales Manager EMC.
“Once the decision is made to case and cement the well and start production an EMC is again lowered with perforating charges. These charges punch holes through the well casing into the surrounding rock formation, connecting the wellbore with the oil and gas reservoir.”
As part of WireCo WorldGroup which manufactures engineers and distributes wire rope, synthetic rope, specialized assemblies, and wire products, Camesa specializes in electromechanical cables (EMC) for the oil and gas industry. “Our products are typically 30,000 foot long steel cables containing a copper conductor in the middle which conducts electricity. They are armored with special galvanized improved plow steel wires or special alloy wires. The corrosion resistant alloys most commonly used are stainless steel 316, GD 31MO, 27-7 MO, and MP35N.”
Corrosive processes
The main corrosive process that Dustin’s team encounters is dealing with sour gas wells. “There are a lot of mature wells that have hydrogen sulfide (H2S) or carbon dioxide (CO2) content. Alloy cables must be used in those wells, although the volume of these which we sell is not high because the cost is significantly higher. As an alloy wireline is five to ten times the price of a ‘normal’ wireline, typically customers will purchase one alloy cable per camp, or even just one per company and use this on a specialized truck to try and make it last as long as possible…”
