Air Drilling - Weatherfords - Basic BHA and Surface Components

Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized deviation • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized deviation • Minimized lost circulation • Minimized deviation • Decreased costs • Minimized lost circulation • Minimized

Air Drilling Services

Get there faster.

Increase ROP and reduce drilling costs through proven engineering and service delivery excellence.

Drilling hazard mitigation

Secure DrillingSM Services- Compression services

Air drillingNitrogen servicesPercussion services

- Downhole tools- Fluid systems- Managed pressure drilling- Pressure-control equipment- Underbalanced drilling

Drilling-with-casing (DwC™) systems Solid expandable systems

Completion

Production

Intervention

Drilling

Evaluation

2 © 2010 Weatherford. All rights reserved.

Air drilling can make the differenceAddress hard formations, lost circulation and deviation

problems to increase penetration rates.

Air drilling is part of our compression services offering and is used through primarily nonhydrocarbon bearing zones to optimize drilling performance. In this type of performance drilling, the bottomhole pressure is maintained as low as possible to increase drilling performance. Reducing the bottomhole circulation pressure significantly increases the rate of penetration (ROP), which ultimately yields the following benefits:

Decreased costs. In hard-rock formations, air drilling provides an ROP that is up to five times faster than drilling with conventional fluids. Air drilling removes cuttings from the face of the bit using high air velocities in the range of 3,000 to 4,000 ft/min (914 to 1,219 m/min). This increased ROP not only reduces costs but brings wells on line faster.

Minimized deviation tendency in faulted formations. Air drilling produces straighter holes with lower bit weights and results in fewer deviation issues while maintaining a good ROP.

Minimized lost circulation compared to conventional fluid systems. Drilling with air, mist and foam—as opposed to conventional mud—reduces hydrostatic pressures and helps manage lost circulation without resorting to costly and time-consuming techniques.


Gasified fluid standard package layout

Air drilling is just one drilling technique in our Secure DrillingSM services suite, which also includes managed pressure drilling and underbalanced drilling. We have the technology, systems and support to help you safely drill your wells, whether you need to drill faster, reduce nonproductive time (NPT) or enhance your well productivity and reservoir recovery.

Type of Air Drilling (Energized Fluid System) Application

Dry air (dust)Hard-rock and dry formationsZero water productionFormation cannot withstand hydrostatic pressure

MistHard-rock formationSmall amounts of water influx

FoamLarge hole diametersMedium amount of water influx

Gasified fluidsLoss-circulation zonesUnconsolidated formations


Get there faster with WeatherfordWe offer a complete air-drilling package.

Performing an air-drilling operation for the first time may appear a daunting prospect, but Weatherford can provide advice and guidance—in the form of expert operations drilling engineering support—to assist you in well planning and programming, as well as rigsite supervision.

As the industry’s largest and most established air-drilling supplier, we have the whole package to help you get the most out of your air-drilling operations, from engineering planning and support to the right products and services for any application.

Engineering planning and supportWeatherford has some of the most experienced air-drilling experts, many of whom came, through acquisition, from the industry’s premier air-drilling companies. Our qualified experts can help with your planning process from project inception to completion.

Start at the beginning with our SURE™ candidate selection process, which improves the success rate of various drilling applications by simplifying the screening of candidate wells and quantifying the potential benefits.

The SURE process is comprised of two main components:

People. Our SURE process team helps you select the most technologically and economically appropriate way to drill a successful air, managed pressure or underbalanced drilling well by quantifying the relationship between reservoir impairment, drilling hazards and NPT associated with conventional drilling.

Proprietary analysis tools. Phase I includes candidate screening via the RST™ reservoir screening tool. Phase II includes an in-depth assessment of drilling processes, including formation-damage evaluation, NPT, performance-drilling evaluation, production forecasting and economic evaluation.

Visit the online SURE selector athttp://sure.weatherford.com.

© 2010 Weatherford. All rights reserved.


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We assist with hydraulic flow modeling during the planning phase of the project. Modeling determines gas rate, fluid rate and injection pressure required to maintain optimal drilling parameters during operations.

Once the air-drilling project has begun, we provide on-site engineering and supervision. And upon completion of the work, we develop end-of-well reports that include information such as operational summaries, lessons learned and future planning.

Enterprise Excellence Process (EEP)

Weatherford’s EEP focuses on creating a preventative culture with error-free performance and empowerment of all employees to achieve continuous improvement in all work processes.

012,795

3,900

13,1234,000

13,4514,100

13,7794,200

Dep

th (f

t/m

)

ROP (ft/hr, m/hr)

14,1084,300

14,4364,400

14,7644,500

15,0924,600

15,4204,700

165

3310

4915

6620

8225

9830

11535

13140

14845

16450

Conventional drillingAir drilling and hammer

ROP comparison between conventional and air drilling


Canada. Air drilling produces significant savings by reducing drilling timeAir-drilling system produced

significant cost savings

by reducing drilling time

on an onshore well, when

compared to conventionally

drilled offset wells. No safety

or environmental issues

occurred during the operation.

The results were considered

to be 50 percent better than

the planned target.

USA. Air-drilling package yields considerable savingsA well that was drilled

overbalanced suffered fluid

losses of 40,000 bbl and had

differential sticking, resulting

in the operation running over

budget by US$6 million.

Using an air-drilling package,

Weatherford drilled an

offset well within the same

formation. This well lost less

than 200 bbl, suffered no

differential sticking and was

completed under budget.

USA. Advanced air-hammer drilling technology produces significant cost savingsOn a Barnett shale well in

Texas, USA, a hammer

tool with light weight-on-bit

and a stabilizer were used

to minimize doglegs and

reduce deviation, resulting

in a savings of 12 to 15 days

of drilling time. A reduction in

deviation by approximately

50 percent enabled

successful completion of the

section in just one bit run.

The operator saved more

than 50 percent in total

drilling costs compared to

conventional drilling methods.

Canada. Performance drilling improves ROP and reduces drilling timePerformance-drilling

techniques were used on

two onshore wells to reduce

drilling time from 35 days

on a conventionally drilled

well to 9 and 11 days on two

additional wells in the same

formation. Drilling costs

were reduced and QHSE

measures were improved.

Latin America (Bolivia). Hot-air injection results in successful foam recycling and increased ROPA hole section was drilled using

hot-air injection into the blooie

line, resulting in a 30 percent

profit in the use of chemicals.

The size of the foam pit was

reduced from 100 to 10 bbl,

the return fluids were recycled,

and ROP was increased up

to five times, compared to

conventional drilling.

Real Results: speeding up operations around the globe



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North Africa (Libya). Air-drilling technique improves drilling performance and minimizes fluid lossBased on offset well

information, total losses were

expected during drilling. The

upper sections were drilled

using aerated mud-drilling

technologies with minimal

loss of drilling fluids into

the formation, resulting in

returns of 100 percent.

Risks and costs associated

with drilling with total losses

were mitigated, enabling

an overall evaluation of the

formation properties and

reducing rig time.

Middle East (Oman). Ultradeep air-hammer success increases ROPUse of Weatherford’s air

hammers resulted in a more

than 20-fold increase in

ROP, resulting in significant

time and cost savings to

the operator. Additionally,

the ability to establish that

both overgauge hole and

deviation were minimal

enabled the operator to

more accurately predict the

next best course of action

to achieve a successful and

cost-effective operation.

Middle East (Pakistan). Foam drilling overcomes loss-zone challenges and improves penetration rateUsing air-foam drilling enabled

the operator to improve

average ROP, saving 4.8 days

of rig time. The concurrent

handling of shale sloughing

by the foam contributed to

the successful setting of the

casing strings.

Asia Pacific (China). Air drilling improves performance, saves more than 100 days of rig time per wellOn average, wells were

being completed in 40 days,

nearly 10 times faster than

comparable offset wells.

In total, use of air-drilling

techniques improved drilling

performance and saved the

client more than 100 days of

rig time per well.

Asia Pacific (Indonesia). Air drilling in geothermal well saves over US$800,000 in drilling costs and reduces mud expenses up to 13 percentUse of the combination

of several Weatherford

air-drilling products

increased ROP by more

than 80 percent, enabling the

well to be completed 6 days

ahead of schedule. Aerated-

fluid drilling helped establish

returns of up to 80 percent

while drilling through a lost-

circulation zone, yielding a

significant reduction in mud

costs and an improvement

in hole cleaning.


Air-drilling equipment: downhole

As the largest air-drilling provider, Weatherford offers a wide array of equipment to help increase drilling performance. Equipment requirement can be divided into two categories—downhole and surface equipment.

Percussion hammers. Use of percussion air hammers requires low weight-on-bit. The weight-on-bit is only enough to ensure that it is in contact with the face of the formation. String rotation in hammer drilling is slower than conventional means, usually between 20 to 45 rpm. The highest ROP in hard rock is attained with air hammers. Air-hammer bits last longer than conventional bits, resulting in longer intervals and single-bit runs. The straightest holes are drilled with air hammers, partly because of the low weight-on-bit and pendulum effect of the bottomhole assembly (BHA). Hammers and bits range in size from 3 1/8- to 29-in. OD.

Percussion hammer bits. Weatherford supplies various air-hammer bits, ranging in size from 3-1/2 to 29 in. Numerous design configurations of bits are available depending on the application. Bits can be designed for any size and special need with appropriate time allocation.

Standard BHA for most hammer operations for surface and intermediate hole sections

Heavy-weight drillpipe (HWDP)

Crossover (XO)

Drill collar (DC)

Bit sub with flapper float

Air hammer

Hammer bit

Weatherford offers a wide variety of hammers and bits that are designed to industry standards.



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Two-phase separationDe-aeration tank (D-tank). A D-tank is an atmospheric tank used in gasified fluid applications and is designed to separate the returning of two-phase fluid into liquid and gas. The function of the D-tank gas/liquid separator is to remove free injected gas from the returning flow when an aerated mud system is used as a drilling fluid. These separators are rigged up on top of the shaker.

BAMBI tank. The BAMBI tank was designed for dust- and mist-drilling applications where it was undesirable to have only a blooie line because of environmental and worksite conditions. Dust on location is kept to a minimum because of the specially designed vortex cluster and water-dampening system. Water can be handled at surface and solids can be sent to the solids handling system.

Air-drilling equipment: surface

Air-compression equipmentPrimary compressor. A primary compressor takes a large volume of air from the atmosphere and compresses it to low pressures—maximum: 350 psi (2.4 MPa). Air volume coming out of the primary compressor feeds the booster compressor.

Booster compressor. A booster compressor is a reciprocating type of compressor that takes a high volume of gas at low pressure—175 to 350 psi (1.2 to 2.4 MPa) from the primary compressors and boosts it to high pressures. Boosters are manufactured for different pressures and volumes. The use of a booster becomes necessary especially in gasified fluid applications where the air-injection pressure must overcome the mud-pump pressure to enter into the liquid phase.

Rotating control device (RCD)The RCD is the barrier between the annular pressure of the well and the rig floor. It diverts flow from the wellbore to the separation unit or settling pit. Weatherford offers an array of RCDs for any environment, including a range of low- and high-pressure options.


The right chemicals for any application

Throughout the planning phase of any air-drilling job, selecting the proper fluid for specific jobs is one of the most important tasks. Weatherford provides one of the broadest product offerings in the industry, including a full suite of chemicals and fluids.

We operate in all major oil and gas sectors across the globe. We offer chemical and operational technical solutions for the management of reservoir and environmentally friendly fluids and corrosion in air-drilling operations.



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Secure DrillingSM services:A better way to drill

Compression services are part of an expanded range of Secure Drilling services that we offer to minimize the risk of drilling hazards related to a wellbore’s pressure profile, and ultimately, to optimize life-of-well performance.

Our Secure Drilling services encompass:

Personnel and asset protection. The use of RCDs to protect wellsite personnel and rig equipment is a cornerstone of our Secure Drilling methodology.

Detection and management. We use advanced identification and control systems to rapidly detect kick and fluid loss, and manage the wellbore pressure profile during drilling operations.

Reservoir evaluation. We draw on our extensive evaluation capabilities to obtain pertinent reservoir data—such as pore pressure, fracture gradient, hydrocarbon composition—that drive drilling and completion decisions.

Performance optimization. Leveraging reservoir data and other resources, we design and implement strategies to optimize life-of-well performance.

weatherford.comWeatherford products and services are subject to the Company’s standard terms and conditions, available on request or at weatherford.com. For more information contact an authorized Weatherford representative. Unless noted otherwise, trademarks and service marks herein are the property of Weatherford. Specifications are subject to change without notice. Weatherford sells its products and services in accordance with the terms and conditions set forth in the applicable contract between Weatherford and the client.

© 2010 Weatherford. All rights reserved. 4564.00


Secure DrillingSM services: offering an alternative to conventional drilling methods when drilling hazards, formation damage and speed are of particular concern. Our Secure Drilling services incorporate several drilling techniques—including air, managed pressure and underbalanced drilling—and associated technologies to optimize drilling performance, minimize formation damage and mitigate hazards.

Visit us at weatherford.com/securedrillingservices, orcontact us at [email protected] for information about…

A better way to drill

Documents

Air Drilling - Weatherfords - Basic BHA and Surface Components