Drilling ChokesProtect your well with dependable, secure pressure control

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Features and Benefits

M-I SWACO* chokes are precision-engineered for accurate well control under harsh, demanding conditions.

10k SUPERCHOKE*, 15k SUPERCHOKE, 20k SUPERCHOKE,10k ESUPERCHOKE*, 15k ESUPERCHOKE

• Designed with half-moon-shapedorifices that allow precise openingand closure

• Positive closure through overlapbeyond the full-close position.Disc-to-disc design is not affectedby pressure drops or surges.

• Tungsten-carbide wear sleevesfor increased in-service life,absorbing the effects of abrasivedownstream turbulence

• Ideal for onshore andoffshore applications

• Can be controlled from either primary or optional auxiliary consoles

10k AUTOCHOKE*, 15k AUTOCHOKE

• Automatically adjusts fluid flowto regulate casing pressure

• Easy, predictable standpipe- pressure control

• No need to fight controlsduring transition operations

• No-leak shut-in with dual sealdesign (metal-to-metal and elastomer-to-metal)

• Rated for H2S service

• Long life in severe service operations

• Excellent flow characteristics

• Self-cleaning orifice reduces plugging

When the pressure is on, ourSUPERCHOKE and AUTOCHOKE tech-nologies give you precise control, providing critical pressure manage-ment when you need it. Formationinflux of high pressure has proven tobe a long-standing, expensive, andpotentially dangerous industry

challenge — one that will never cease.That’s why M-I SWACO engineers haveput more than 50 yrs of skill andproven tech nical performance intochoke development, providing opera-tors with reliable, responsive controloptions to keep pressure in its place.

Reliable, responsive performance under pressure

� A P P L I C A T I O N S

Land or offshore conventionaldrilling; the special demands ofUnderbalanced Drilling (UBD), Coiled-Tubing Drilling (CTD), frac flowbackand Managed-Pressure Drilling(MPD); Equivalent Circulating Density(ECD) control; H2S applications; andwell-control and cleanup operations.

� P R O B L E M S

During controlled-pressure drilling,management of formation pressurescan be critical. An uncontrolled pres-sure influx can result in dangerouskicks and well-control problems.

� S O L U T I O N S

M-I SWACO solutions address all yourwell-control needs. SUPERCHOKE unitsfor shutting in the well, determiningcirculating pressure, breaking circula-tion, maintaining constant casing anddrill-pipe pressure; AUTOCHOKE unitsfor breaking circulation and main-taining constant casing, drill pipeand set-point pressure; ESUPERCHOKE

units for automated control.

� E C O N O M I C S

The reasonable costs associated withchoke rental are more than offsetby the control that can save yourwell. Well control is the most critical component in any drilling program.

� E N V I R O N M E N T A L

In addition to keeping your well freeof kicks and blowouts, maximum con-trol over fluid loss and reduced waterrequirements help to minimize a project’s environmental footprint.

The M-I SWACO AUTOCHOKE unit isideal for use as a pressure-relief“valve” for frac flowback work.

The M-I SWACO AUTOCHOKE unit pro-vides automatic, precise pressure con-trol. It is the best choke technologyavailable today for UBD and MPDapplications. The AUTOCHOKE unitregulates casing pressure automati-cally under all conditions for a widerange of tasks: regulating mud pumpstart-up or shutdown, making andbreaking drill-pipe connections, orallowing mud/gas flows alternatelythrough the choke.

Stripping pipe is simpler and saferwith the AUTOCHOKE unit due to itsability to maintain casing pressure.As drill pipe is lowered into the hole,an equal volume of fluid under pres-sure is automatically displacedthrough the choke.

Advantages• High pressure rating

— 10k psi (689 bar)— 15k psi (1,034 bar)

• Maintains casing pressure— Dynamically positioning

shuttle. Automatically adjustsfluid flow to regulate casingand drill-pipe pressures.

• Bottomhole Pressure (BHP)— Precise control. The precise

control of the AUTOCHOKE

unit can dynamically main- tain BHP when controlled pressure drilling is required.

— Results in less rig downtime.Maintaining the BHP at ±50 psi(3.4 bar) during well-control ordrilling operations can reducethe circulation time by at leastone complete circulation whenremoving gas from the wellbore.

— Reduces fluid-loss expense.Automatic adjustment duringwell-control operations mini-mizes the occurrence of over-pressuring the formation andthe resultant fluid loss.

• Frac flowback— Ideal for use as a pressure relief

“valve” in frac flowback work.The hardfaced wear sleeve andthe tungsten carbide down-stream sleeves stand up to thehighly abrasive sand flow offrac operations.

• Compliance— M-I SWACO is licensed to manu-

facture drilling chokes and con-soles under API 6A & 16C and incompliance with NACE MR-01-75.

• High-capacity– High-capacity 3-in. (76-mm)

choke bore. Improved flow char -acteristics at throttle point andthrough choke bore.

– Self-cleaning orifice. Reduces plugging.

• Preset maximum pressure capability

• Downstream choke-bore protection– Tungsten-carbide sleeves.

Extended-wear sleeves increasein-service life and absorb theeffects of abrasive downstreamturbulence and protect the APIring gasket.

• No-leak shut-in seals and long-life materials– Metal-to-metal and elastomer-

to-metal seals. Constructed oflong-life components for severeservice operations: tungsten-carbide static trim, reversibledynamic trim, hard-faced (satellite) shuttle assemblyand internal removable bodysleeve. Chrome-plated internalbores for corrosion resistance.

AUTOCHOKE control consoleThe AUTOCHOKE console is con-structed of stainless steel and is complete with drill pipe and casing-pressure gauges, a hydraulic oilpump control regulator, a hydraulicoil set-point gauge, and a hand- operated hydraulic backup pump.The AUTOCHOKE console is equippedwith an electronic position indicator,digital pump-stroke counters with arate meter, stop watch and clock.

The M-I SWACO AUTOCHOKE

Temperature API API Length Width Height Weight rating Bore size Pressure inlet flange outlet flange

psi (bar) in. (mm) in. (mm) in. (mm) lb (kg) ° F (° C) in. (mm) psi (bar) in. (mm) in. (mm)

10,000 41.51 11.50 16.31 580 –20 to 250 3 10,000 3.06 (78) 3.06 (78)(689) (1,054.3) (292.1) (414.3) (263) (–29 to 121) (76) (689) x 10,000 psi x 10,000 psi

(689 bar) (689 bar)

15,000 44.26 12.50 19.75 700 –20 to 180 3 15,000 31⁄16 (77.8) 31⁄16 (77.8) (1,034) (1,124.2) (317.5) (501.7) (317.5) (–29 to 121) (76) (1,034) x 15,000 psi x 15,000 psi

(1,034 bar) (1,034 bar)

Control console

10,000 24 26 55 655 (689) (610) (660) (1,397) (298) N/A N/A N/A N/A N/A

15,000 35 28.5 57 730 (1,034) (889) (724) (1,448) (332) N/A N/A N/A N/A N/A

Specifications: AUTOCHOKE

How it worksThe unique design of the AUTOCHOKE

unit features a dynamically positioning

shuttle that moves back and forth on an

axis housed inside of a hardfaced wear

sleeve. The shuttle seats into the 3-in.

(76-mm) diameter orifice in the static

trim piece. Hydraulic pressure (adjusted

through a set-point pressure regulator)

is applied to the back side of the shuttle.

This creates a pressure-balanced situa-

tion between the casing pressure of the

well and the hydraulic pressure of

the choke.

If the casing pressure is higher than

the hydraulic pressure, the shuttle moves

back and clears the orifice. If the casing

pressure is lower than the hydraulic

pressure, the shuttle moves forward

and closes the orifice. As the shuttle

moves back and forth, it regulates

the flow of fluid or gas from the well

through the 3-in. (76-mm) orifice.

Shuttle

Shuttle nut Inlet

Dynamictrim

Extended trim

DischargeLong trim

Static trim

Fully closed

Hydraulic set-point pressure

Shuttlesliding Casing

pressure

Hydraulic set-point pressure

Casingpressure

Static trim

Hydraulic set-point pressure

Shuttle sliding Casing

pressure

Static trim

Dynamic trim

Passing debris

Fully opened

Widely used and respected for well-kill and high-pressure drilling, the M-I SWACO SUPERCHOKE product lineis especially effective in well control,well testing, and well cleanup opera-tions. These chokes are effective inH2S and abrasive-fluid applications.

Advantages• High-pressure rating

— Built to handle 10,000 to20,000 psi (689 to 1,379 bar)• 10,000 psi (689 bar)• 15,000 psi (1,034 bar)• 20,000 psi (1,379 bar)

• Dependable choke-disc design— Heavy-duty, diamond-lapped

tungsten-carbide discs honedto near-perfect flatness. Also fea-ture half-moon-shaped orifices.Rotation of actuator fork allows

finite regulation of the openingsize from full-open to full-close.

• Positive closure— A 17° deadband overlap beyond

the full-close position ensures closure even if the plates becomeworn following extended expo-sure to abrasives-laden fluid flow.Quality of the seal is not affectedby pressure drops and surges.In fact, the seal improvesunder pressure.

• Tungsten-carbide sleeves— Increase in-service life. Extended-

wear sleeves absorb the effects ofabrasive downstream turbulenceand protect the API ring gasket.

• Versatility— Ideal for onshore and offshore

applications. Controls can beoperated from either primaryor optional auxiliary consoles.

• Three operating modes— Normal. Activation is

rig-air operated.— Lost rig air. Activation is manual

with hydraulic pump located onremote-control skid.

— Severed hydraulic lines. Activationis manual with bar provided onindicator head.

• Compliance— Constructed for H2S service.

M-I SWACO is licensed to manufacture drilling chokesand consoles under API 6Aand 16C and in compliancewith NACE MR-01-75.

Control consolesM-I SWACO choke-control consolesare available to control either a sin-gle or twin SUPERCHOKE unit. Theseconsoles are equipped with eitherstandard or optional digital gauges.Hydraulically operated consoles areself-contained and skid-mounted foreasy installation on or near the rig.

A key feature of the consoles arethe large, easy-to-read gaugeswhich monitor critical drill-pipeand casing pressures.

The M-I SWACO SUPERCHOKE

TemperatureLength Width Height Weight rating Pressure

psi (bar) in. (mm) in. (mm) in. (mm) lb (kg) ° F (° C) psi (bar)

10,000 35.7 21.6 11.5 441 –20 to 250 10,000 (689) (906.8) (548.6) (292.1) (200) (–29 to 121) (689)

15,000 43.3 21.6 11.5 600 –20 to 250 15,000 (1,034) (1,099.8) (548.6) (292.1) (272) (–29 to 121) (1,034)

20,000 43.4 24.3 13.2 650 –20 to 250 20,000(1,378) (1,102.4) (617.2) (335.3) (295) (–29 to 121) (1,378)

Control consoles

Single 55 27 65 588(1,397) (686) (1,651) (267) N/A N/A

Dual 55 27 69 690(1,397) (686) (1,753) (313) N/A N/A

Specifications: SUPERCHOKE

The ESUPERCHOKE unit is theM-I SWACO standard SUPERCHOKE

unit; it incorporates an electric motor actuator and an electronic console.

Advantages• High-pressure rating

— Built to handle 10,000 and15,000 psi (689 to 1,034 bar)

• Cold weather The electric motor and electronic con-sole replace the air-over-hydraulicconsole and improve reliability incold-weather environments.

• Small footprintThe electronic console’s quietand space-saving design allowsthe console to be located in thedriller’s cabin.

• Reduced cabling requirementsThe ESUPERCHOKE unit requires onlyone communication cable betweenthe remote and local console.

• Three modes of operation— Remote at driller’s console— Local at the choke manifold— Manual at the choke itself,

using the hand-wheel

• High torqueThe ESUPERCHOKE system is capa- ble of more than 19,400 in.-lb(2,191.9 Nm) torque. It can sever a∑-in. (12.7-mm) alloy steel rod andstill achieve the full-close position.

• Variable-speed driveThe operator can control thespeed at which the choke isopened or closed, giving the oper -ator precise choke-positioningadjustment during critical well-control situations.

• Faster open/close speedsEight seconds from full-open tofull-close. This time exceeds thatof a hydraulically actuated chokein cold-weather environments.

• Enhanced communication capabilityThe ESUPERCHOKE system recordsdata via Ethernet to external data-acquisition systems, greatly enhanc-ing the ability to evaluate fracflowbacks, well-control problems,and leak-off tests in real time.

The M-I SWACO ESUPERCHOKE

TemperatureLength Width Height Weight rating Pressure

psi (bar) in. (mm) in. (mm) in. (mm) lb (kg) ° F (° C) psi (bar)

10,000 38.5 14.38 21.38 525 –20 to 250 10,000 (689) (978) (365) (543) (238) (–29 to 121) (689)

15,000 47.38 14.75 25 775 –20 to 250 15,000 (1,034) (1,203) (375) (635) (352) (–29 to 121) (1,034)

Control consoles

Single 18 10 14 60(457) (254) (356) (27) N/A N/A

Dual 18 10 14 60(457) (254) (356) (27) N/A N/A

Specifications: ESUPERCHOKE

P.O. Box 42842Houston, Texas 77242-2842

www.miswaco.comE-mail: questions@miswaco.com

Technology Centers:

HOUSTON, TEXASTel: 281·561·1300 · Fax: 281·561·1441

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Technical Service Centers:

NISKU, ALBERTA, CANADATel: 780·955·3388 · Fax: 780·955·2064

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BERGEN, NORWAYTel: 47·55·173850 · Fax: 47·55·173851

DUBAI, U.A.E.Tel: 971·4·8830644 · Fax: 971·4·8837197

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©2008 M-I L.L.C. All rights reserved. *Mark of M-I L.L.C.

DBR.0301.0808.R1 (E) 2.5M Litho in U.S.A.

This information is supplied solely for informational purposes and M-I SWACO makes noguarantees or warranties, either expressed or implied, with respect to the accuracy and useof this data. All product warranties and guarantees shall be governed by the Standard Termsof Sale. Nothing in this document is legal advice or is a substitute for competent legal advice.