Connecting Dots with Lines Using Drilling Software

Posted on August 20, 2013 by Gefei Liu, PVI

Dots are isolated incidents, individual cases, snap shots, discrete numbers, etc. Looking at dots, we obtain limited information, but more often, we miss the big picture if our vision is restricted to the dots only.

One of the uncertainties in torque and drag analysis for drilling is the friction factor, because it is dependent on many things such as mud type (oil-based or water-based), pipe moving in casing (steel) or in open hole (rock), cutting concentration, etc. If we can observe hookloads or surface torque for certain operation at various depths, we can calibrate friction factor (back calculation). The following picture is a screen from TADPRO (torque and drag model). You can see from the dots (field measurements) and the lines (model prediction) that the friction factor of 0.32 is a good estimation for slack off operation.

Individual case study with one set of input data only tells one story. If we can compile the output from multiple runs of computer model, we can see the trend. This process is automated in many of our drilling software models. The following pictures show the impacts of open hole excess on top of cement (TOC) and hydrostatic pressure difference.

We call this powerful feature of automatic run on multiple cases “Sensitivity Study”.

Steve Jobs once said this in his famous commencement address to Stanford University: “You can’t connect the dots looking forward; you can only connect them looking backwards. So you have to trust that the dots will somehow connect in your future.”

Connecting dots in our lives gives us confidence to follow our hearts even when it leads us off the well worn path. Connecting dots in drilling engineering reveals the trends of operation date and window of safety to operate.

Let our drilling software assist you connect more dots.

Drilling Software Training in Snow

Posted on August 13, 2013 by Gefei Liu, PVI

No matter how unpredictable the weather is, drilling software can predict downhole conditions.

One would never think that Denver in May requires a winter coat. That was my judgment before I came here to teach a drilling software course. I did briefly check the weather website and I saw 70 °F. So I assumed a warm spring in the mile-high city. Upon my arrival on April 30^th, I became aware that snow was coming and I felt the temperature dropping as evening was coming. I did not bring any jacket. I went to the stores along the street but could not find any coat. See, even the stores thought the winter is over. I finally bought a winter coat in a souvenir store: after all, it is better to spend money on cloth than cold medicine. Surely enough, the snow came as predicted during the night. Here is the picture of downtown Denver on May 1^st, 2013.

Modern technology, particularly computers and weather satellites, and the availability of data provided by coordinated meteorological observing networks, has resulted in enormous improvements in the accuracy of weather forecasting, despite of people’s intuition. To better prepare our daily life, we do need to pay attention to the hard-to-understand red/green/yellow images on TV.

Snowflakes danced outside the window all day long as I taught 7 drilling engineers from the Rocky Mountain region the HYDPRO software (drilling hydraulic model).

Drilling software, in a sense, is much like weather forecasting for an upcoming drilling operation. With planned well path trajectory and proposed operation parameters, engineering software can pinpoint potential problems and make necessary adjustments on operation. The potential economic benefits of accurate drilling engineering modeling are immense. For example, drillpipe or casing buckling is always a concern during drilling and casing running operations. TADPRO (torque and drag model) predicts the locations of different buckling modes. The following screen shot from TADPRO shows the sinusoidal and helical buckling sections along a drillpipe.

Generally speaking, sinusoidal buckling can be tolerated, while helical buckling should be avoided, because helically buckled pipe creates additional drag, which could lead to “lock up” situation.

It is often quoted: Everyone talks about the weather, but no one does anything about it. We cannot change the weather except predict it. In other words, we react to the prediction. However, drilling software like TADPRO can alert engineers the potential downhole problems prior to the operation so necessary measures can be taken to prevent it. This improves safety, saves time and money, and reduces risks.

We use weather forecasting to plan our daily activities. Similarly, drilling professionals should use drilling software to do well planning. The future belongs to people who can predict and prepare for it.

What Is Common between Elevator and Drilling Software?

Posted on August 6, 2013 by Gefei Liu, PVI

Creativity, life or business each has its up and down, like an elevator. This article was triggered by an elevator in a hotel I stayed in Erbil, Kurdistan, Iraq. I spent one week there providing cementing software training to a fast-growing service company in the region.

One time I stepped into the elevator and accidently pressed ④. The button ④ lit up. My room was at level 5. Realizing the mistake, I pressed ⑤. Then, just out of curiosity, I pressed ④ again. To my pleasant surprise, the light on ④ was turned off. You know what? The elevator did not stop at level 4.

Here are the 2 pictures I took later to reproduce the steps.

My past experience told me that if I press wrong buttons, I have to forgive myself, either patiently wait for the unscheduled stop or let the elevator stop at untended level after I leave.

This new experience let me wonder why they design their elevators differently. There must be reasons behind the design of elevator control panel. As a software developer, I find this new way of design the most natural. Because round buttons representing the hotel floors are actually check boxes: riders can change mind to go to room first instead of heading to gym. Plus, adding this “Cancelling” or “Checking off” feature does not affect other normal selections.

During software development process, developers use many controls in the graphical user interface (GUI). Among those controls, a radio button or an option button (⊙) is a type of element that allows the user to choose only one of a predefined set of options. On the other hand, a check box (☑)permits the user to make multiple selections from a number of options or to have the user answer yes (checked) or no (not checked) on a simple yes/no question.

In our drilling software such as MUDPRO(drilling mud reporting), we use these controls extensively. For example, in generating daily mud report, we provide checkboxes and options, allowing mud engineers to tailor the contents and style of the report.

Checkboxes and options in MUDPRO Daily Report

Problem of programming a bank of elevators is often used as exercise for students majoring in computer science. The software program is to control the actions of each elevator, based on the information of the state of each button on the floors and inside the elevators, as well as the time elapsed since each floor-button is pushed. Drilling software provides technical solutions to the engineering problems in drilling operations, based on the operation parameters. The commonality of any programming tasks is to test the functionality and usability from a user’s prospective. This process requires constant exchange, back and forth between developers and users. This is also one of the reasons why upgraded versions are necessary. Software is not only a product, but also a process of improvements. This new control panel in the elevator might be an upgraded version.

MUDPRO, when generating the end-of-well recap, memorizes the users’ setting such as shown in the following graph, so the user can generate recap in the same style.

MUDPRO report memorizes users settings

Our office is in a 5-story building. I take elevator at least twice a day. In the future, there might be elevators that can recognize the frequent-rider like me through eye recognition and automatically memorize where I am going. Of course, it will allow me to cancel my selection and visit my travel agent on the 3rd floor.

I am still dreaming… Elevator chime sounds. My floor is here and I got to go. Have a good day and I see you next time.

Drilling Hydraulics Software Training in Bolivia

Posted on July 30, 2013 by Gefei Liu, PVI

As part of the software sale to a service company in Bolivia, software training was conducted in Santa Cruz of Bolivia, the 2^nd largest city in the country.

Being south of equator, it is summer in Bolivia. Hot and humid, the weather is similar to Houston’s a few months ago. I immediately got used to it, until I was woken up by big noise of birds this morning. You know what? They are parrots singing in the giant tree in front of my room. That was a pleasant surprise. Those birds would be very nice pets in Houston. Although I don’t speak their language, I knew they were very happy.

Our training was on drilling hydraulics (HYDPRO). We had a dozen of students ranging from seasoned mud engineers to newly graduates. The biggest challenge I faced was the communication: they speak more English than I do Spanish. None was sufficient to understand each other. We had a couple of engineers, educated in US, interpreting for everyone.

The teaching went smoother when I started to demo HYDPRO. HYDPRO does have an option to switch to Spanish, which means all captions including those in reports could be in Spanish. But even without using the local language, our students had fairly grip in understanding the program structure and logic flow.

I think their knowledge of drilling fluid, mud engineering and hydraulics helps them tremendously. And I also think we did a good job in interface design so that it breaks language barriers for our users whose native language is not English.

After all, drilling operations are similar across the world. We speak different languages, but we use API standard drill pipe, casing, and handful rheological models to describe fluid behavior. Our drilling software is a tool beyond boundaries, which can be used by drilling engineers in North America, South America, and any other continents.

One student in the training showed me a programmable scientific calculator, using which he had coded a remarkably drilling hydraulics program. Here is the picture of his “Hidraulica de perforacion”.

This is the picture of our HYDPRO training.

My first trip to Bolivia was fruitful. I am sure I will come back for business or vacation: my visa is valid for 5 years with the onetime fee of $125!

Paper and E-reader vs. Book and HYDPRO

Posted on July 23, 2013 by Gefei Liu, PVI

“Paper: The original wireless communication”. This is a sentence in Sappi Fine Paper North America’s eQ Journal 004. So interestingly stated, it tells a lot about human being’s communication need in the age of a digitalized world. “The World Wide Web, far from decreasing paper consumption, served to increase the amount of printing done at home and in the office.” Abigail J. Sellen and Richard H. R. Harper wrote in “The Myth of the Paperless Office”. After people began to use e-mail in the 1990s, paper consumption is estimated to have increased by some 40%. Neither is eBook device nor screen likely to make print on paper obsolete.

For my own reading pleasure, I use these 2 devices whenever I travel.

The convenience of carrying hundreds of books in one device allows me to switch between the books with a great flexibility, although I still enjoy reading paper books in my backyard. The tactile sensation of fingers turning fine-grain papers and the smell of ink and paper are also parts of reading experience. Developed 2000 years apart, paper and digital technologies not only co-exist, but also enhance the synergy between them as paper is routinely converted to digital documents and digital documents to paper.

We also see this 2-way conversion in the engineering efforts of drilling software developments. In 2012, Prof. Boyun Guo from University of Louisiana at Lafayette and I jointly wrote a book about drilling hydraulics (Applied Drilling Circulation Systems).

This book covers many areas of hydraulics concerns of drilling and mud engineers, with theories, examples, and operation guidelines: a good source of information and knowledge for petroleum engineering students and engineers.

Quite a few years ago, PVI developed its popular drilling hydraulics software HYDPRO which addresses majority of drilling hydraulics including frictional pressure drop, ECD, bit optimization and hole cleaning etc.

Similar technologies, delivered in traditional paper and the state-of-the-art application, serve drilling engineers’ essential need to understand and optimize drilling hydraulics. Equations in the book are the DNA of the HYDPRO, while the software is the screen play of the book.

Drilling software like HYDPRO is a great vehicle to carry the heavy loads of technologies. Yet, it provides engineers with easy-to learn and simple-to-use experience.

Friction: Drilling Engineers’ Friend and Foe

Posted on July 16, 2013 by Gefei Liu, PVI

Friction, the resistance force between two rubbing surfaces, the very drag consumes our energy while we walk, run and drive, also prevents us from falling, colliding and accident.

Friction is everywhere. We can see it painting on roads when car makes sudden stop. We can hear it screaming when wheels stop rotating while car keeps the momentum. We can smell its anxiety when Native Indians rotate drive in wood making fire. These are some appearances of friendly sides of friction. And sometimes, we need to amplify its power by the means like the following.

For downside, we have seen plenty in our daily lines. Our shoe wears out (so our feet do not). We dress smart phone up by putting screen or cover so that scratch (a form of friction) only damages the dress, not the body.

This is friction: we hate, love and cannot get rid of it. And we had better use it toward our advantage.

In drilling and completion practices, we encounter friction whenever we move tubular inside wellbore. When moving pipe downward such as in drilling and casing running, friction slows us down. If we move pipe upward such as in trip-out, friction is pulling pipe down. Yes, friction always acts in the opposite direction of the moving object.

In torque and drag analysis, one graph is worth noting: the hookload for trip-in and trip-out operations, as shown here.

The green line is the hookload when pipe is stationary inside wellbore at various depths.

The blue line shows the hookload when pipe is moving downward. The red line is the hookload when pipe is moving upward.

Note that during trip-in, the frictional drag is against the gravitational force, so the hookload is smaller than the hookload during trip-out, when the frictional drag acts with the gravitational force.

In other words, during trip-in, friction helps hook to hold the pipe weight, while during trip-out, the friction is on the same side of gravitation to make hookload higher.

For coiled-tubing (CT) operation, since CT has relatively thin wall (could be as small as 0.125 inch), the tensile limit of CT may not withstand the pulling of drag and weight during trip-out, as shown in the following graph.

We can run the CT into a deviated well. However, we may not be able to pull the same CT out of the hole!

Friend or foe, friction shows up in various fashions. We just need to know his characteristics and dance with him.

Keep Drilling Software Easy - Really Easy

Posted on July 9, 2013 by Gefei Liu, PVI

We all know that any joke we have to explain is probably not worth telling. To some degree, it is the same thing when it comes to creating a user interface for drilling software. Every developer has his or her own insight on interface designs, and has them all neatly explained for the customers. But if we have to do that much explanation to our software users, we probably have not designed an easy-to-use product.

As computers become faster, information explodes and schedule gets tight; all of us, including drilling professionals, face the challenge to finish more tasks in less time. Software enables us to do so.

Software is the child of both developer and user. However, not all software is born equal. Software developers and users live in separate worlds. We developers are in our universe of coding and users are in their reality.

To users, software is a tool to make a job done. Their goal is to use software as few times as possible.

To developers, software coding is our mission, to combine our solid professional skills and elaborate interface designs to make sound software. Sometimes, we tend to make things more complicated than necessary. Part of the reason is that it is easy to do so: just by not planning carefully. On the other side, to make a complicated model easy to use is difficult and time-consuming. However, the hours developers put into programming is well worth, because once the difficulty-made-easy tasks are done in a software, it benefits hundreds of users. The benefits multiply as more people start to use software.

Just like a good joke is the one without having to explain, a good software should be so intuitive and easy that a manual is not needed.

So, keep drilling and keep drilling software easy – really easy.

Drilling Software: A Bridge between Research Efforts and Field Executions

Posted on July 2, 2013 by Gefei Liu, PVI

The term R&D or research and development refers to a specific group of activities within a business. There are 2 main goals of an R&D project: develop new products and discover/create new knowledge.

In our drilling community, we have seen many R&D projects with various sizes and duration. Petroleum engineering departments of many universities receive grants from industry and conduct specific tasks. On a big scale, joint industry projects (JIP) gather resources from different companies, both operators and service providers. I was involved in some big JIP projects such as DEA-44 (Horizontal Technology), DEA-42 (Casing Wear Technology) etc. By the way, DEA here stands for Drilling Engineering Association, not Drug Enforcement Administration. Many R&D projects produce great know-how and sometimes prototype products. However, we need a vessel to package the knowledge from these R&D efforts.

Software naturally becomes the form to hold the knowledge. With graphical user interface (GUI), it can become a powerful tool for end users, who often are not involved in the project.

An R&D project without action is incomplete. A software package serves as a bridge between the gap of research results and field executions. For example, not many people understand how the equation of force balance is used to calculate torque and drag along a drill string or casing, but most drilling engineers understand the hook load and surface torque charts. As a matter of fact, we don’t have to be able to solve numerical equations to be drilling engineers. The advanced engineering and calculation capabilities are already packed in the ready-to-use software like TADPRO (torque and drag model).

If not for exercising purpose, you probably want to ride to office than walk. You probably want to take bridge than take boat to reach the other end.

Let our drilling software help you drill more efficiently.

Drilling Software Is Like Movie

Posted on June 25, 2013 by Gefei Liu, PVI

In Dubai, I took some time off and went to watch the 3D movie “Life of Pi”. It is a beautiful movie in many ways. I watched it again on my flight to Houston.

I guess that movies touch more hearts than novels. Most people enjoy movies more than novels, probably because not many people have the luxury of reading a 200+ pages novel. I saw the novel (book) of Life of Pi in our local library, but it did not take me much time to decide not to borrow it. Another reason movies are more popular is that movies are the results of careful selection. Producers and directors must be extremely scrutinizing in selecting interesting or inspiring stories to base movies on.

Writing a novel is creativity in action. Translating a story into a movie or TV program is another form of creativity, requiring collaborative efforts from teams of talents. By comparison, we can tell that writing is more like playing solo in creating stories while movie making requires high technologies, performance, music, a pool of talents.

It is hard to say whether movie directors benefit more from writers or other way around to create a blockbuster sensation. It takes the best of both worlds to create a film like Life of Pi.

In a similar way, researchers and engineers write technical papers and create models. But the gap between researchers and field engineers is big. The theories developed by researchers sometimes are hard for field engineers to comprehend. Researchers may not fully understand the situations field engineers face.

Drilling software is like a movie based on certain stories (theories and models). Software developers are like movie makers, translating abstract equations into visual interfaces, often using hi-tech development tools.

A good software requires a technically sound model, carefully architected structure and easy-to-use navigation interface. The advanced model provides a solid base to construct a functional structure. Careful design makes sophisticated models appear simple and creates pleasant user-experience.

It is a leap from a script (model or theory) to a lively movie!

MUDPRO: leap from paper to electronic reporting

Gym Going and Software Using

Posted on June 18, 2013 by Gefei Liu, PVI

You probably just graduated from college. You have prepared yourself with knowledge and skills gained through years in school. And now, you are building up a career in petroleum industry.

You probably have been going to gym regularly, running on elliptical or crunching weights to make sure you look great, right? No doubt, a great physique is the foundation of success. It helps project a professional image of a young and energetic drilling engineer.

Unfortunately, this is only the 1^st step to achieve your goal. You have a great vessel. Now it is time to put treasure of real world experience and know-how into it. They say: “Time is the best teacher.”, but this best teacher also kills all his students.

Fortunately, drilling engineering software such as PVI’s HYDPRO (drilling hydraulics) and TADPRO (torque and drag) can expedite your experience gaining process. You do need to go to field to obtain 1^st hand experience. You can run tens or hundreds of drilling simulation using software in one day. Each simulation is a possible field observation. In short time, you mature in the drilling engineering area and you are still young! You amplify your skill using software and you talk like seasoned engineers even though you look green.

Now, look at yourself in the mirror and you nod at yourself: “I am cool and ready to shake hand with world.”

Pegasus Vertex, Inc. – Blog

Breakroom for Drilling Professionals

Category Archives: Articles