Well control for pre-salt production efficiency

Baker Hughes has been developing completion technology and well control with Petrobras in deepwater ever since its first intelligent completion system contract in the early 2000s. Claudio Paschoa found out more.

Baker Hughes’ well stimulation vessel Blue Shark in Rio de Janeiro. Photo by Jean Mathiel.

Baker Hughes entered the Brazilian market in 1973, when Hughes Tool Company acquired its representative bit manufacturing facility in Salvador, the capital of the state of Bahia.

Since the very start, the company established itself as a major drill bit supplier in the Brazilian oil industry, entering into other sectors, including well control and completion in around 1978. Today, Baker Hughes is one of Petrobras’ preferred partners in pre-salt development.

In early 2000s, Baker Oil Tools was awarded Petrobras’ first-ever intelligent completion system contract, for the deepwater Marlin field, and Baker Hughes has been developing completion technology and well control with Petrobras in deepwater ever since.

Mauricio Figueiredo is Baker Hughes’ vice president of business development at its regional headquarters in Rio de Janeiro. Figueiredo has been with Baker Hughes for all of 35 years, starting as a trainee in 1978, at about the same time that Baker Hughes launched its Brazilian company, and worked his way up to the position of vice president for Brazil, where he managed Baker Hughes’ business, 2008-2013. In his current position, as vice president, business development–a role he assumed in October 2013–he oversees all Baker Hughes’ business with Petrobras on a global scale.

“With the decrease in Petrobras’ drilling operations, as the national operator increased focus on development of pre-salt fields and reduced exploratory activity, business for us in Brazil began decreasing in 2013. This was also caused by the decreased activity of private local companies and international oil companies (impacted by lack of bid rounds for five consecutive years). We believe this is only temporary though and business should pick up again by 2016,” Figueiredo says.

Intelligent well system

Decreasing costs and reducing risks through a partnership with Petrobras in tackling drilling challenges led Baker Hughes to sign a cooperation agreement with the national operator in 2009, for well construction, reservoir analysis, and artificial lifting research and development, based at Baker Hughes’ Rio de Janeiro technology center. Petrobras invested US$16.4 million and Baker Hughes injected US$29 million in the project.

The collaboration is focused exclusively on developing technology to solve Petrobras’ challenges. “We started with a major investment with our drilling and evaluation business, and during the last seven years, Baker Hughes has had more than 50% of the directional drilling market with Petrobras,” Figueiredo says. “In addition, we’ve invested a lot in subsea completions, establishing an important leadership position for our artificial lift business in deepwater environments. We have around 60% of that market share. This represents a huge growth from seven or eight years ago, and it has a lot to do with having the right strategy in place and pursuing the most promising opportunities in the market, not only with Petrobras, but with other companies, as well. It also has to do with understanding our customer needs and delivering above their expectations.”

“Baker Hughes and Petrobras have a long and successful history of joint technology development for addressing pre-salt challenges, and this has led to important breakthroughs in pre-salt development,” Figueiredo says. Since 2005 Baker Hughes has invested around $300 million in Brazil (infrastructure, technology tools and personnel qualification), much of which was earmarked for pre-salt fields development. At the Marlin field in 2003, Baker Oil Tool’s InCharge Intelligent Well System proved to be ideal by being user-friendly and by its all-electronic design, which incorporated a one-penetration approach and a power-on-communications architecture that required little to no retrofit of existing subsea trees. This helped in terms of decreasing customer OPEX. “The system now has been greatly developed, with new tools and techniques implemented, which has greatly increased the overall scope of the Intelligent Well System and enhanced its capabilities, in order to deal with the specific challenges posed by ultra-deepwater pre-salt wells, which are spudded into geologically complex reservoirs,” Figueiredo says.

FASTrak from Baker Hughes. Photo from Baker Hughes.

Although there is no well control technology development being done at Baker Hughes’ technology center in Rio at the moment, the center has been instrumental in creating, developing and implementing dependable high performance solutions to maximize production and recovery since its inauguration. The oil and gas industry has generally defined intelligent wells as wells equipped with downhole remote flow control devices used to open, close, or regulate flow from and to multiple zones without the need for well intervention.

“Intelligent wells completion systems are usually complemented by downhole permanent monitoring systems, which provide valuable information used in the decision making process for the control of production or injection. All these systems require multiple control lines and cables to link the downhole tools to the associated surface equipment, which serves as the interface between the operator and the system,” Figueiredo says.

In subsea systems, the wellhead and wet X-mas trees are installed on the seabed, providing a means of controlling the wells through a series of valves, piping, chokes and other related equipment. Deepwater subsea trees are operated by remote-control systems, through hydraulic actuators. The well control systems on the surface are linked to the trees by means of dedicated lines in an umbilical or by sophisticated electro-hydraulic multiplex systems mounted on the trees, controlled through a subsea electronic module. Figueiredo explains that, “The electro-hydraulic multiplex systems are becoming more popular because of their quicker response time, increased reliability, and lower umbilical costs. These subsea control systems not only need to control functions on the trees, but also need to be able to interface with and control downhole equipment, such as safety valves, downhole chemical injection valves, permanent monitoring instrumentation, and intelligent well valves.”

Penetrations through the tubing hanger provide a means of communication between the subsea control system and the downhole equipment. Subsea control systems normally have two hydraulic circuits for controlling downhole functions: one high pressure (HP) normally dedicated for the safety valve and one low pressure (LP) normally used for the intelligent flow control valves.

“Baker Hughes’ completion fluids for the pre-salt are well developed and do not constitute a major challenge. We have drilled over 80% of pre-salt wells in the Santos Basin,” Figueiredo says. These presalt optimized completion fluids are designed to ensure a smooth transition between the reservoir drilling and the completion phases. There are clear brine fluids, filtration units, viscosifiers, filtration control agents, scavengers, and surfactants. Each serves a special purpose in providing the best possible wellbore scenario for intelligent well completion operations.

Well monitoring instrumentation measures pressures, temperatures, flow rates, water cut, and density in the wellbore with both electronic and fiber optic gauges and are key components in intelligent completion technologies. This instrumentation includes zonally isolated, hydraulically adjustable valves and chokes, which allow adjustments to product inflow from any zone, without well intervention. Water and gas can also remotely control the flow to individual zones. The SENTRYNET chemical automation tools allow control of the chemical regimen at remote oil and gas production facilities, such as pre-salt areas in Brazil. Another essential part of intelligent well systems, feed-through packers, offer a way to pass downhole tool control lines through the packers while controlling fluid flow and maintaining production zone isolation.

Mauricio Figueiredo, vice president- business development, in his office in Rio de Janeiro. Photo by Claudio Paschoa.

“Corrosion is always high and can be a very costly problem in the pre-salt wells. For this reason Petrobras has been gravitating to special steel materials, more resistant to the corrosion from salt formations. This special steel, in conjunction with corrosion inhibitor, is designed to work in a variety of brines and water-based fluids, along with keeping CO2-caused corrosion in check, limiting its destructiveness. So corrosion is a challenge that has been in most cases addressed and can now be effectively controlled,” Figueiredo says. Over the years, Figueiredo adds, the Petrobras and Baker Hughes partnership in the pre-salt development has led to a 40% increase in pre-salt drilling operations efficiency and it was Baker Hughes that did the completion of the first pre-salt well with an intelligent well system installed to monitor and control a deep, dual-zone, gas-injector well at the Lula field (former Tupi field), in the Santos Basin, leading to its use in other Brazilian pre-salt plays.

“Petrobras’ requirements for the future, include: a better understanding of reservoir heterogeneity in the complex microbial carbonate environments; faster, safer drilling and high quality wells in very challenging ultra-deepwater environments; intelligent production systems and overall completions technology that uses materials and equipment customized for the characteristics of the developments; Improved reservoir hydrocarbon stimulation techniques and well integrity dependability in unstable thick salt layers,” Figueiredo says.

Baker Hughes also has the majority of the well stimulation vessel market in Brazil and has three stimulation vessels under an exclusive contract to Petrobras, the Blue Shark, the Blue Angel and the Blue Marlin, all based in Niteroi. Pressure-pumping operations perform between 1200 and 1300 jobs a year, including cementing, stimulation, coiled tubing services, wellbore cleanup, casing running, completion tools, filtration fluids and chemical services.