Not only are reamers important for directional drilling, but they can also be useful in straight hole applications. Reaming assemblies can straighten out and smooth over crooked holes, restore undergauge holes to gauge, and get rid of any irregularities or keyseats. They also help to prevent excessive hole curvature in short intervals, which may be experienced when entering and exiting a section of hole which forms a sharp curve. Finally, reamers can reduce the rotational torque in a wellbore, and may therefore be used as a substitute for a conventional string or near-bit stabilizer.
Reamers are made by almost all major downhole tool manufacturers, and have the same core features: sealed or open (mud lubricated) bearings, cutter types – either “nobbly” or “smooth”, and either one (so called “3-point”) or two (“6-point”) sets of cutters in a tool.
Reamer (Courtesy of NOV, 2017)
Between the fracture pressure and the pore pressure of the formation, the hydrostatic pressure of drilling fluid will always be maintained according to conventional drilling practice. In order to control the transport cuttings to the surface as well as the formation fluids, the drilling fluid is held within the wellbore where it circulates. Furthermore, it also keeps the drill bit cool and lubricated as it acts as a stabilizing agent. For effective use, the fluid must be water- or oil-based and this leads to a maximum weight of 19 pounds for each gallon (minimum of 7.8 pounds). As an attempt at imparting fluid loss, density, and rheological properties, it also contains a mixture of liquid and solid products.
Figure 1 – Conventional Drilling
For many years, the conventional drilling has been the safest method when drilling a well but there are also some negatives to using the method. For example, fluid invasion is a common problem because the drilling fluid pressure is naturally above the pressure of the natural formation – this can cause permeability damage. Also, physical blockages and washouts are common as the solids and fluids lodge into the formation. Continue reading
Wild Well Control is one of the best well control specialist companies in the world. The company not only provide well control and engineering services to the company’s customers, it also provides free technical knowledge to the public such as Wild Well Control Technical Book that you can download it for free. Today, we would like to review one of the most useful presentation which is “Well Control Methods” presentation. After you read the review and you like it, we also provide download link for you at the end. Thank Wild Well Control for great contribution to oil and gas industry.
Well Control Methods by Wild Well Control, Wild Well Control (2017)
Transocean Ltd. (NYSE:RIG) announced Tuesday that its ultra-deepwater drillship Deepwater Invictus has been awarded a two-year contract with options by a subsidiary of BHP Billiton.
Transocean said the backlog associated with the firm contract is approximately $106 million and the contract will commence in the second quarter of 2018. It includes three one-year priced options.
The Deepwater Invictus was delivered in 2014 and is rated to a water depth of 12,000 feet. It has spent nearly its entire career contracted to BHP.
Deepwater Invictus – (MarineTraffic,com, 2017)
Offshore platforms are used to explore, extract, and process oil and gas retrieved from the seabed. One vital part of these structures is the central processing platform (CPP), where the well head fluid is pumped from the wellhead platforms through the riser for processing. The most important function of the CPP is to separate the oil, gas, and water from this three-phase well head fluid, to produce the final product of the platform.
Most central processing platforms feature the following components:
1. Separation Unit
2. Gas compression and dehydration
3. Produced water conditioning
4. Sea water processing and injection system Continue reading