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www.Fisher.com

Design TBX Blowdown Fixture

Introduction

Scope of ManualThis instruction manual includes installation andoperation information for the Design TBX BlowdownFixture for bolted bonnet TBX valves. Pipingblowdown is very important to successful plantstartup and trouble free operation. The plan forpiping blowdown should be undertaken byprofessionals familiar with all aspects of blowdownoperation. This manual is not intended to cover alldetails required for successful piping systemcleaning.

Key numbers identified for valve disassembly areshown in the specific valve instruction manual. Referto separate instruction manuals for instructionscovering the exact valve, actuator and accessoriesassociated with the blowdown fixture.

No person may install, operate, or maintain a DesignTBX Blowdown Fixture without first being fullytrained and qualified in valve, actuator, andaccessory installation, operation, and maintenance,and carefully reading and understanding thecontents of this manual. If you have any questionsabout these instructions, contact your Fisher salesoffice before proceeding.

DescriptionThe Design TBX Blowdown Fixture provides aconvenient way to clean piping upstream of thevalve while taking care not to damage internal valveparts.

Note

Fisher does not assume responsibility

for the selection, use, or maintenanceof any product. Responsibility forproper selection, use, andmaintenance of any Fisher productremains solely with the purchaser andend-user.

Principle of OperationThe Blowdown Fixture replaces the valve plug andcage and allows steam flow from the upstreampiping to be directed through the valve and out thevalve outlet and downstream piping.

Maintenance

WARNING

To avoid personal injury or propertydamage from release of pressurizedprocess media, ensure that the systemis completely depressurized andappropriate safety measures havebeen taken prior to carrying out any ofthe following maintenance procedures.Only trained competent individualswith the proper equipment shouldattempt to disassemble and install aBlowdown Fixture, and reassemble aTBX valve.

Always wear protective gloves,

clothing, and eyewear whenperforming any maintenanceoperations to avoid personal injury.

Check with your process or safetyengineer for any additional measuresthat must be taken to protect againstprocess media.

Valve DisassemblyThe following valve disassembly steps are intendedas a quick reference only. Refer to the TBXinstruction manual, form 5769, for further detail

regarding valve disassembly.

Actuator Removal The following actuator disassembly steps areintended as a quick reference only. Refer to the

Instruction ManualForm 5792December 2004 TBX Blowdown Fixture

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TBX Blowdown FixtureInstruction Manual

Form 5792December 2004

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appropriate actuator instruction manual for furtherdetail on actuator removal.

1. Release the actuator seat load by either manuallystroking the valve or applying the appropriateinstrument signal. The stem connector may beremoved once the plug is off of the valve seat.

2. If an instrument signal has been used to strokethe plug off the seat, remove the signal only afterremoving the stem connector.

3. Isolate and disconnect the operating lines fromthe actuator.

4. Loosen the yoke fasteners and remove theactuator from the valve.

Packing Box Unbolt the packing stud nuts, (key 68), and removethe packing flange (key 66) and packing follower,(key 65) (reference appropriate instruction manualfor key numbers (key)). Remove as much packing aspossible from the packing box.

CAUTION

Extreme care should be taken to avoidscratching the stem or the packingbox.

Bonnet and Trim 1. Loosen the bonnet nuts, (key 55) using an evenand opposing pattern (for example, if the first nutloosened is at the 1 oclock position, the next nut tobe loosened would be at the 7 oclock position). Thiswill prevent uneven loading of the bonnet flangestuds, which may cause binding.

The nuts should not be completely loosened whilethe remaining nuts are tight. It is suggested that atleast two stages of loosening be used to avoidoverloading the last few remaining studs.

2. Remove the bonnet (key 6) from the valve withuni-axial pull. If the bonnet seems to bind in thevalve body, check the alignment of the hoist orpulling mechanism. Deviation from an axial pull ofthe parts may result in galling or bending of thestem.

Do not attempt to overpower any binding, asdamage to the guide surfaces may result.

The bonnet may be lightly tapped back intoalignment with a soft face mallet. The stem and plugshould be pushed back into the valve body while thebonnet is being removed. Once the bonnet isremoved, dislodge any remaining packing rings fromthe packing box.

3. Remove the packing ring (key 63) from thebottom of the packing box. Lightly sand the inside ofthe packing box with 60 or 80 grit paper to removeany adherent packing material. Final cleanup shouldbe made with 160 grit or finer paper.

4. Inspect the bonnet guiding surfaces and gasketmating surfaces. Light damage on the guidingsurface may be repaired with an emery cloth or othersuitable material. Damage to the gasket matingsurface may require bonnet replacement to avoidleakage.

5. Remove the plug assembly (key 22, 23, and 53)as a single unit by grasping the valve stem (key 23)and pulling the assembly from the body cavity. Theplug assembly contains sensitive guiding andsealing surfaces on its outside diameter and caremust be taken in its handling. The plug should betemporarily stored on a clean wooden or clothsurface.

6. Remove the cage (key 21) from the valve body.Remove and discard the upper and lower cagegaskets (key 43). Reference the TBX valveinstruction manual for guidance in performing thisdisassembly. The cage contains sensitive guiding

surfaces on its outside diameter and care must betaken during handling. The cage should betemporarily stored on a clean wooden or clothsurface.

7. Clean and inspect the guiding and sealingsurfaces of the plug assembly. For balanced plugdesigns, inspect the piston ring (key 45) andBore Seal ring (key 46) for signs of excess wear ordamage and replace if necessary. The piston ring isa two piece design with an outer seal ring and aninner expander ring. The outer ring diameter shouldbe expanded beyond the diameter of the plug in itsfree state. It can be shifted within its groove toinspect for uneven wear around its circumference.The piston ring should require some compressionwhen installing the plug into the cage. Lack ofrequired compression indicates that the piston ringhas worn or relaxed and should be replaced. Verticalmarks in the axial orientation also indicate wear thatrequires replacement of the ring. The Bore Sealring has a C-shaped cross section with the openportion of the C-shape facing the stem side of theplug for flow-up designs. Any uneven marks aroundthe circumference of the ring or any flattening of the

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TBX Blowdown FixtureInstruction ManualForm 5792December 2004

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ring shape at its outside diameter are indications ofwear and require replacement. Contact your Fishersales office for Bore Seal ring replacement.

8. Clean and inspect the inside diameter surfaces ofthe cage. The entire length of the cage insidediameter is either a sealing and/or guiding surfaceand any measurable wear requires that the cage bereplaced.

9. The seat ring remains retained inside the valvebody. Clean and inspect the angled seating surface.Any detectable damage around the circumference ofthe seating surface is an indication of wear andrequires reconditioning to ensure seatingperformance. Contact your Fisher sales office forspecific instructions on reconditioning the seatingsurface.

10. Remove all used gaskets and foreign matterfrom the interior of the valve and from the inlet andoutlet openings. Remove any foreign matter thatmay be in the valve trim. Inspect all valve bodyguiding and sealing surfaces for any signs of wear.

Visual Inspection Visually inspect the interior of the valve for abnormalwear, signs of erosion, or scoring if the valve hasbeen in service. All scores and scratches should beremoved by grinding or filing to remove anyinterference of the clearance zones between theinternal bores and the mating parts. The affected

area should be sanded with 100 grit or finer paper.Do not attempt to completely remove the score, onlythe interference should be removed and sanded.

The gasket surfaces of the valve body and bonnetshould be inspected to verify that they are notdamaged and are free of imbedded gasket material.

Installation of the Blowdown PlugInspect the valve to ensure that all parts and gasketshave been removed and the valve body is free from

foreign debris. Lubricate the inside and outside ofthe seat lip and the upper valve body bore andcounterbore. Install the trim as illustrated in theBlowdown Fixture drawing, figure 1.

1. Place the lower cage gasket (key 43) into thevalve body.

2. Insert the Blowdown Plug into the valve bodymaking sure that the gasket remains properlyplaced.

Table 1. Recommended Bonnet Bolt Torque (1)

Bolt Size, Inch Threads Per InchRecommended

Bolt Torque,lbf ft(2)

1 8 405

1.125 8 5501.25 8 730

1.375 8 980

1.5 8 1290

1.625 8 16501.75 8 2070

1.875 8 25602 8 3130

2.25 8 4490

2.5 8 62003 8 10800

1. Torque values for lubricated threads.2. Torques for studs with heavy hex nuts.

3. Place the upper cage gasket (key 43) on top ofthe flange of the Blowdown Plug.4. Lubricate the bonnet studs and lower the bonnetonto the valve body, making sure that the uppercage gasket remains in the gasket containmentgroove.5. Lubricate and tighten the bonnet fasteners asrecommended in the TBX valve instruction manual.Torque values are also shown in table 1 of thisdocument.

CAUTIONFailure to comply with goodbody-to-bonnet bolting practices andthe torque values shown in table 1 orin the appropriate valve instructionmanual may result in damage to thevalve.

Piping Blowdown with the BlowdownFixture Installed

WARNING

To avoid personal injury or propertydamage from blown out debris, takeappropriate measures to stay clear ofthe outlet of the blowdown pipingduring the following procedure.

Note

The following steps are not intendedto be complete instructions for

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performing a proper systemblowdown. They are intended only toaddress the basic issues required forproper piping blowdown.

1. Perform piping blowdown according to plantstartup procedures. Normal blowdown proceduresshould incorporate piping velocities in excess ofthose anticipated during maximum system operation.Piping should be blown down until two subsequentchecks of a target placed at the outlet of theblowdown piping indicate that all debris has beenremoved from the piping.

2. At the completion of the blowdown procedure,secure and depressurize the system.

Disassembly of the Blowdown Fixture1. Loosen the bonnet nuts, (key 55) using an evenand opposing pattern (for example, if the first nutloosened is at the 1 oclock position, the next nut tobe loosened would be at the 7 oclock position). Thiswill prevent uneven loading of the bonnet flangestuds which may cause binding.

The nuts should not be completely loosened whilethe remaining nuts are tight. It is suggested that atleast two stages of loosening be used to avoidoverloading the last few remaining studs.

2. Remove the bonnet from the valve with uni-axialpull. If the bonnet seems to bind in the valve body,check the alignment of the hoist or pullingmechanism. Deviation from an axial pull of the partsmay result in galling or bending of the stem.

Do not attempt to over-power any binding, asdamage to the guide surfaces may result.

3. Remove and discard the upper cage gasket (key43).

4. Remove the Blowdown Plug from the valve bodycavity using the integral eyebolt holes in theblowdown plug.

5. Remove and discard the lower cage gasket (key43).

CAUTION

To avoid compromising the service life

of the TBX valve body and/or trim, donot reuse the Blowdown Fixturegaskets for valve reassembly.

Cleaning After removal of the Blowdown Plug, the interior ofthe valve body should be rinsed with clean water orrepeatedly wiped with clean towels until the surfacesare clean to the touch. All internal parts should becleaned prior to reassembly.

ReassemblyRefer to the TBX valve instruction manual forguidance in reassembling the valve.

Ordering InformationInformation required to order a Design TBXBlowdown Fixture.

Valve Serial Number

Valve Tag Number

Customer Order Number

Valve Model Number

Blowdown Fixture Design ConditionsFlushing Fluid

Flushing Fluid Pressure

Flushing Fluid Temperature

Material (carbon steel unless otherwisespecified)

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BONNET(KEY 6)

Figure 1. Blowdown Fixture

LOWER CAGEGASKET(KEY 43)

BONNET STUDS/NUTS/WASHERS(KEYS 54, 55, 52)

UPPER CAGEGASKET(KEY 43)

BLOWDOWNPLUGKEY 3

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FisherMarshalltown, Iowa 50158 USACernay 68700 FranceSao Paulo 05424 BrazilSingapore 128461

Emerson Process Management

www.Fisher.com

The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability.We reserve the right to modify or improve the designs or specifications of such products at any time without notice.

Fisher does not assume responsibility for the selection, use or maintenance of any product. Responsibility for proper selection, use andmaintenance of any Fisher product remains solely with the purchaser and end-user.

Fisher Controls International LLC 2004; All Rights Reserved Printed in USA

Fisher is a mark owned by Fisher Controls International LLC, a member of the Emerson Process Management business division of EmersonElectric Co. The Emerson logo is a trademark and service mark of Emerson Electric Co. All other marks are the property of their respective owners.

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