Fusion Procedures

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Bulletin No.101

Fusion Procedures

for Joining PLEXCO@

PolyethylenePipe and Fittings

CONTENTS3

Fusing Sockets 5

Fusing Service Saddles and

Tapping Tees -8

17

PLEXCO Fusion Time Cycles 18

This literature is written to assist Field Personnel in theuse of PLEXCO procedures for joining PLEXCO poly-ethylene pipe and fittings by socket, saddle and buttfusion techniques. PLEXCO recommends these tech-niques as the preferred method for joining PLEXCOpolyethylene pipe and fittings.

PLEXCO POLYETHYLENE PIPING PRODUCTSCANNOT BE JOINED BY SOLVENT CEMENTING.THREADED JOINTS AND JOINTS MADE BY HOTAIR (GAS) OR EXTRUSION WELDING TECHNIQUESARE NOT RECOMMENDED FOR PRESSURESERVICE. If you use compression fittings or othermechanical fittings or electrofusion fittings, instructionsshould be obtained from the fittings manufacturer.

When you buy the PLEXCO polyethylene pipingsystem, you obtain quality products made to rigidspecifications and the selection of socket or buttfittings for pipe sizes 4" IPS and smaller. 6" IPS andlarger fittings are butt fusion type only.

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When PLEXCO polyethylene pipe is to be joined toanother piping material, a transition fitting may beused to resist pull out forces due to seasonal sub-surface temperature changes or from anticipatedexternal or internal loading. Compression or othermechanical type couplings may be used to join poly-ethylene to other piping materials; however, manufac-turers of these fittings must be consulted regardingsuitability and installation procedures necessary tomeet system design requirements.

The quality of the Piping System is also dependenton proper handling of pipe and fittings. Polyethylenepipe should not be handled with chains or draggedover sharp rocks or other abrasive objects. Canvasslings or padded fork lifts should be used wherecontact is directly with the pipe surface. The pipeshould be stored in a manner that minimizes thepossibility of crushing or piercing.

Important: All fusion Equipment must be in properworking order. Consult the manufacturer's operatingmanual for maintenance and service procedures.Do not use defective equipment.

Fusion is Accomplished in

Four Simple Steps.

1. Be sure that the surfaces of the fusion tools, pipe,and fittings are free of contaminants prior to use, andproperly prepared for fusion.

2. The surfaces to be joined-both the pipe and fitting-are simultaneously heated by the fusion tool at a speci.fied temperature for a specified time.

3. Remove the fusion tool, then bring the meltedsurfaces together.

4. Hold until solidified. The fusion yields a strong

integral joint.

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water, slurries, and

other applications.

Here's What Fusion is All About

PLEXCO Polyethylene Pipe and Fittings are joined bya simple heat fusion procedure. All PLEXCO socketfusions can be done by hand with the prescribedtools. However, it is recommended that fitting holdersbe used for fitting sizes 3" IPS and larger. Saddleapplication tools are recommended for applying tap-ping tees, service saddles and branch saddles. ThePLEXCO butt fusion system requires tools for all fusionoperations. Clean surfaces, accurate heating iron sur-face temperature, and a proper melt pattern are keysto a good joint.

.Check heating iron fusion surface temperature withtemperature indicating crayons or pyrometer.

.Clean heater faces after every joint with woodenimplement (NEVER use metal tools).

.Do a trial fusion at the start of each day.

.To remove static electricity prior to cutting or tappinga pressurized gas line, spray polyethylene pipe withwater/soap solution or water/glycol solution andground with a solution wetted cloth.

.Fusion equipment may not be explosion-proof-take safety precautions if fusing in a combustibleatmosphere.

.Shield fusing equipment from inclement weatherand winds.

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.Make sure all tools are clean and fit for the job.

.Inspect polyethylene pipe for cuts, gouges, anddeep scratches, and remove these pipe sectionsbefore fusing the pipe.

.Remove tension* in the line before making anyconnections.

.Make sure the correct time and temperature areused.

.Square pipe ends to remove any damaged or"necked down" surface-

.Wipe pipe ends with CLEAN dry cotton rag toremove any foreign substance and cuttings fromI.D. (avoid rags of synthetic fiber that may melt andchar against heater surface).

.See additional information on Page 18.

*If direct burial, polyethylene pipe should be snakedin the ditch and the temperature of the pipe shouldbe approximately the same as the soil at the installeddepth before completing the tie-in. Fusion of coilsshould be done so that the joined coils form an "S"to reduce stress at the joint. If the polyethylene pipehas been inserted in an existing line, it should beallowed to cool to the casing pipe temperature priorto final tie-in. For each 10°F temperature drop, 100feet of polyethylene pipe shrinks approximately one(1) inch.

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Fusing Sockets

You'll need these tools:

To obtain quality fusions, a trial fusion should be madeeach day to check required heating times for prevail-ing ambient temperature and other weather conditions.

1. Square the ends of the pipe or tubing to be joined.

Pipe & TubeCutter

DepthGauge

ChamferingTool

Cold Ring

Clamp

SocketFaces

Use Pipe Cutter for cutting polyethylene pipe. (A hacksaw may be used. Use particular care to producea clean square cut end.)

2. Use Chamfering Tool on pipe ends to remove thesharp outer edge on the O.D. surface on all pipe sizes.Female

FaceMaleFace

Remove any burrs from inside of pipe ends. Makesure both ends of pipe to be joined are clean, dry, andfree of foreign substances. Wipe with clean, lint-free,

dry rag.

Here's how to fuse Sockets

These socket fusion procedures should be followedcarefully when joining PLEXCO pipe to socket typecouplings, tees, ells, reducers, and end caps.

Pipe and fitting sizes 2" IPS and smaller are quicklyjoined by hand. When fusing pipe and fitting sizes 3"IPS and larger, holding tools are desirable.

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7. When the Heating Tool fusion surfaces have reacheda temperature of 500°F :t 10°F (as indicated bytemperature crayon or pyrometer), you are ready forthis step, not before.

Firmly seat the Socket Fitting on the male face of theHeating Tool. If pipe joiner is being used, this operationis accomplished in the same manner.

Place the female face of the Heating Tool on the end ofthe pipe firmly against the Cold Ring Clamp. If pipejoiner is being used, place the female face on the endof the pipe in the fixed Cold Ring Clamp of the joiner:

Heating time starts when the cold ring is bottomed outon the heater surface. Heat for prescribed period oftime shown in Recommended Fusion Time Cycleschart on Page 19. DO NOT TWIST PIPE, FITTING,OR HEATING TOOL.

8. Snap the Heating Tool from the melted pipe and fit-ting by a sharp rap on the iron handle with free handwhile holding upper part of tool handle in the oppositehand in such mannner that the melt will remain intact.

9. Quickly check melt pattern on pipe surface andfitting-heated surfaces on fitting and pipe should be100% melted with no cold spots. If melt is notcomplete, cut off melted pipe end, use a new fittingand repeat fusion Steps 1 through 8.

3. To measure proper socket insertion depth, placeDepth Gauge snugly over the chamfered end of thepipe.

4. Install Cold Ring Clamp on pipe O.D. surface im-mediately behind Depth Gauge. After securing ColdRing Clamp, remove Depth Gauge.

ALTERNATE:4. In case where pipe joiner is being used, place theend of the laid pipe line in the fixed Cold Ring Clampof the joiner and the free coil or joint in the movableCold Ring Clamp. Use Depth Gauge as stated above.

5. Make sure fitting surfaces are clean and dry. Wipeagain with lint-free, clean, dry rag if necessary. Avoidtouching cleaned surface with your hands.

6. If you haven1 already done so, heat Heating Tool withfaces attached so that the faces are at 500°F :t 10°F.Make sure faces are clean. Use wooden tongue de-pressor (or comparable wooden implement) to removeany molten polyethylene from fusion faces. DO NOTuse metal implements to clean non-stick, coated fusionfaces as they will damage the surface.

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10. Within 3 seconds after the Heating Tool has beenremoved, firmly push the melted fitting squarely ontothe pipe end until it makes firm contact with the ColdRing Clamp. DO NOT TWIST PIPE OR FITTING.Hold the fitting firmly in place for total cooling time(see Recommended Fusion Time Cycles on Page 19)to insure proper alignment. If pipe joiner is beingused, this operation is performed in the same manner.

NOTE: Misalignment will displace the melt and createa faulty fusion.

After waiting an additional 3 minutes cooling time,remove the Cold Ring Clamp and inspect the joint.A good joint will have a flat, uniform melt ring and join-ing perpendicular to the pipe, with no gaps or voidsbetween the fitting and the pipe.

ALTERNATE:10. If the joiner is being used, repeat the fusion steps(from step 5) on the free coil or joint to be fused intothe socket fitting. The handle is used to advance thepipe on and off the heater faces and finally into themelted socket fitting opening.

Hold the fused joint firmly in place the entire coolingtime. Wait an additional 3 minutes cooling time. Removethe Cold Ring Clamp and inspect the joint. A good jointwill have a flat, uniform melt ring joining perpendicularto the pipe, with no gaps or voids between the fittingand the pipe.

11. Wait an additional 10 minutes to complete coolingbefore the pipe joint is tested or stressed during burial.Be sure backfill is free of rocks and large clods ofearth to prevent damage to pipe line. See PLEXCOApplication Note No. 7-Pipe Embedment and FinalBackfilling.

12. If the steps outlined in this fusion technique werefollowed carefully, an acceptable joint should havebeen made.

13. Consult PLEXCO Bulletin No.105, .'QualificationProcedures for Making PE 2406 Polyethylene HeatFusion Joints," or PLEXCO Bulletin No.106,.'Qualification Procedures for Making PE 3408Polyethylene Heat Fusion Joints" for techniques usedto evaluate the quality of the joint.

14. Clean heater faces carefully after each fusion, withwooden tongue depressor or wooden stick. Do notuse metal implements to clean heater faces.

CAUTION:The final tie-in of the line should not be made until thepipe has cooled to the temperature of the ditchbottom. On hot days, this allows pipe to shrink beforethe tie-in is made.

CAUTION:In sections where a fitting is present, the bendingradius should be limited to 120 to 125 times the pipediametel: Polyethylene pipe without fittings can bepermanently bent to a radius 20 to 25 times the pipediameter without damage or effect on its physicalproperties.

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FusingService Saddlesand Tapping TeesYou'll need these tools:

~Preparation

1 .Place application unit on main according tomanufacturer's instructions. Unit should be centeredover cool, clean, dry location where the fitting will befused. Secure unit to main. A bolster plate isrecommended for 6" IPS and smaller sizes.

2. Install correct heating faces on heating tool andheat tool so that fusion surfaces are at 500°F =1: 10oF .

3. Insert fitting in application unit and place fittingbase on pipe. Secure fitting tightly in unit.

4. Raise fitting and abrade fusion surface of fittingbase and main with utility cloth (50 to 60 grit).Periodic replacement of cloth is necessary .

After abrading, brush residue away with a clean, drycloth.

Heating5. After heater faces reach 500°F :t 10°F, placeheating tool on main centered beneath fitting. WITHIN3 SECONDS, place fitting against HEATING TOOL,AND QUICKLY apply and maintain CONTINUOUSpressure during heating. (LONGER THAN 3SECONDS COULD CAUSE EXCESSIVE HEATPENETRATION OF THE MAIN.) Heating time startsafter fitting and pipe are firmly seated against heaterfaces. Heat for prescribed period of time shown inRecommended Fusion Time Cycles chart on page19, or until melt bead size shown below is visible oncrown of main. During heating, the heating iron maybe rocked slightly, about 2 deg., to assure full contactwith the main. DO NOT INTERRUPT HEATING TOINSPECT THE MELT PATTERN ON THE MAIN.

Here's how to fuse Service Saddles and

Tapping Tees with an application unit.

When service line is to be connected to a main atsystem gas pressure, a Tapping Tee is recommendedfor the Hot Tap.

IT IS RECOMMENDED THAT AN APPLICATIONTOOL BE USED WHEN MAKING SADDLE FUSIONJOINTS. Variables in the installation procedure aremore easily controlled when a tool is used than whenthe fusion is made manually.

IMPORTANTVarious tool manufacturers' tapping tee fusionapplication units have slightly different operatingprocedures. Consult the manufacturer's operatingmanual for proper use of the tool.

When fusing on a pressurized main, the risk ofblow-out can be reduced by using equipment thatis in proper working order, following the manufac-turer's operating instructions, using recommendedfusion procedures and by using relieved-centerheater faces when fusing High Volume TappingTees.

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FORCE APPLIED DURING HEATING AND COOLINGTapping Tees and Service

SaddlesHVTT and Branching

SaddlesPipe Size

1-1/4" thru 8", When the main is not under internal pressure, a

fusion/cooling force of 40-80 Ibf is acceptable for allsizes of tapping tees and service saddles.

'* When the main is not under internal pressure, a

fusion/cooling force: for 2" of 60-80 Ibf, for 3" of80-100 Ibf; and for 4", 6" & 8" of 90-120 Ibf isacceptable for HVTT and branching saddles.

minutes and High Volume Tapping Tee and BranchSaddle fusions to cool an additional 30 minutes, thencut off top of fitting to prevent use. After propercooling time, relocate fusion application unit andrepeat procedure from Step 1.

(A mirror may be used to check the melt on the undersurface of the saddle base.)

Fusion and Cooling

7. If melt patterns are satisfactory , press the fitting onthe pipe very quickly (within 3 seconds after removingheater) with firm pressure until a melt bead of thefollowing size appears around the entire base of thefitting:

Place fitting against heater faces. Apply and maintainpressure during heating. Heating time starts after fittingand pipe are firmly seated against heater faces. Heatfor prescribed period of time shown in RecommendedFusion Time Cycles chart on Page 19 or until meltbead size shown below is visible on crown of main.During heating, the heating iron may be rocked slightly,about 2,0 to assure full contact with the main.

Approximate Melt Bead Size

Bead ThicknessPipe Size

1-1/4" 1/32"2" 1 /16"

3" & Larger 1/8"

6. After proper melt bead has developed, remove fittingfrom heater and heated from main with quick snappingactions.

Quickly check melt pattern on pipe surface andfitting-heated surfaces on fitting and pipe should be100% melted, no cold spots.

If surfaces are unacceptable, continue with steps 7 and8, do not reapply heater, allow Standard Tapping Teeand Service Saddle fusions to cool an additional 10

ApproximatePipe Size Fusion Bead Size

1-1/4" 1/16"2" 1/8"

3" & Larger Larger than 1/8"

Adjust fusion unit to maintain pressure of fitting on pipe.Allow fusion joint to cool for the time indicated inRecommended Fusion Time Cycles chart on Page 19.

8. After letting joint cool an additional 3 minutes,remove application unit from pipe. Visually check fittingfor fusion bead around entire fitting base. If beadpattern on fitting or pipe is unacceptable, allowStandard Tapping Tee and Service Saddle fusions tocool an additional 1 0 minutes and High Volume TappingTee and Branch Saddle fusions to cool an additional 30minutes, then cut off top of fitting to prevent use. Afterproper cooling time, relocate fusion application unitand repeat procedure from Step 1.

9. For Standard Tapping Tees and Service Saddles, letfusion cool an additional 1 0 minutes prior to pressuretesting or tapping the main. Allow an additional 30minutes before tapping or pressure testing High VolumeTapping Tees or Branch Saddles.

10. If the steps outlined in this fusion technique werefollowed carefully, an acceptable joint should have beenmade.

11. Consult PLEXCO Bulletin No.105, "QualificationProcedures for Making PE 2406 Polyethylene HeatFusion Joints," or PLEXCO Bulletin No.106,"Qualification Procedures for Making PE 3408YELLOWSTRIPE@ Polyethylene Heat Fusion Joints" fortechniques used to evaluate the quality of the joint.

12. Clean heater faces carefully after each fusion, withwooden tongue depressor or wooden stick. Do not usemetal implements to clean heater faces.

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The Use of Application Tools vs.

Hand Application

PLEXCO recommends the use of application toolsrather than hand application for the saddle fusion ofPLEXCO Standard Tapping Tees, High VolumeTapping Tees, Service Saddles, and Branch Saddles.

2. Place the cap on the body and turn counter-clockwiseuntil the leading edges of the threads clear each otherand the cap drops onto the second thread. Witha marker such as a felt tip pen, mark the top of thecap in line with the service outlet.

3. Screw the cap clockwise about 12 to 12-1/2 turns.An additional 1 /4 to 1/2 turn is permissible if neces-sary; however, tightening beyond 13 turns may over-tighten and damage the o-ring seal.

Branch Saddles

Branch Saddles may be applied in the same manneras Service Saddles. A Branch Saddle application unitis recommended for this operation.

CAUTION:In sections where a fitting is present, the bendingradius should be limited to 120 to 125 times the pipediameter: Polyethylene pipe without fittings can bepermanently bent to a radius 20 to 25 times the pipediameter without damage or effect on its physical

properties.

High Volume Tapping Tee

Fusion procedures for High Volume Tapping Tees arethe same as for Standard Tapping Tees excepting heat-ing and cooling times. Prescribed time cycles areshown in Recommended Fusion Time Cycles chart onPage 19.

Procedure ForTightening Tapping Tee Caps

PLEXCO Tapping Tee Caps are designed for use with.out lubricants. Lubricants can lead to over-tighteningwhich can damage the o-ring seal or lead to capfailure.

Standard Tapping Tee Caps should be secured byhand. Check to be sure the o-ring is in place at thetop inside of the cap, and the threads and sealing sur-faces are free of dirt and contaminants. Screw the capdown until resistance is felt, then about 1/6 to 1/3turn more.

For service main pressures up to about 60 psig,High Volume Tapping Tee Caps should be securedby hand. Check to be sure the o-ring is in place atthe top of the body, and the threads and sealingsurfaces are free of dirt and contaminants. Screw thecap down about 12 turns then about 1/2 to 3/4 turnmore to complete the seal.

For service main pressures above about 50 psig,a band or strap type wrench (such as an oil filterwrench) may be used to secure High Volume TappingTee Caps. Jaw type wrenches with teeth are not rec-ommended as the cap may be damaged.

1. Check to be sure the o-ring is in place at the top ofthe body, and the threads and sealing surfaces arefree of dirt and contaminants.

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Tapping the Main:Standard & High Volume Tapping Tee-Hot Tap and Cold Tap

Place Tapping Tee Wrench in hex opening of cutter attop of tee. Turn wrench clockwise until washer contactstop of tapping tee-this will make the tap. The sectioncut from the pipe wall (coupon) will remain in the cut-ter. Turn wrench counterclockwise until top of cutter iseven with top of tapping tee. Remove the wrench butDO NOT REMOVE THE CUTTER. I nstall cap in ac-cordancewith procedures on Page 10. Pressure test inaccordance with company approved procedures.

Priortotapping the main, the service line should befused to the Tapping Tee. Before fusing the service lineto the Tapping Tee, slide a protective sleeve (sized to fitthe Tapping Tee outlet) over the free end of the serviceline. Then fuse the service line to the Tapping Teeoutlet. Fuse the opposite end of the service li ne to themeter riser or service connection.

Pressure test all fusions including the saddle base ofthe Tapping Tee and the service line at the tee andmeter riser or service connection.

You are now ready to tap the main.

CAUTION:After saddle fusing Standard Tapping Tees and ServiceSaddles, let fusion cool an additional 10 minutes priorto pressure testing or tapping the main. A/low an ad-ditional30 minutes before tapping or pressure testingHigh Volume Tapping Tees or Branch Saddles.

Now slide protective sleeve over outlet end of thetapping tee and secure with plastic tape to avoid slip-page of sleeve during backfill operation.

The installation is now complete and ready for backfilling

Tapping the Main:

Branch Saddle-Hot Tap

Due to the many tools and methods to produce a BranchSaddle hot tap, PLEXCO will supply appropriate in-formation for this procedure upon request.

Tapping the Main:Service Saddle andBranch Saddle-Cold Tap

When the main is not pressurized, tapping can bedone with a simple T -bar tool with cutter. Simultane-ously push on the tool into the outlet end of the ServiceSaddle or Branch Saddle and turn clockwise. Thistaps the main. Rotate the tool counterclockwise andpull to withdraw the cutter-the section cut from thepipe will remain in the cutter and is removed by usinga screwdriver as a probe or pry bar in the slot pro-vided in the sidewall of the cutter. The cold tapping iscompleted. This tool has built-in stops to preventdamage to the inner wall of the main opposite the tap.

To fuse the service line to the Service Saddle, slidea protective sleeve over the service pipe. Socket fusethe service line into the Service Saddle outlet. Secureopposite end of the service line to the meter riser.Allow an additional 10 minutes prior to pressure testingor stressing. Pressure test all fusions including thesaddle base and service line at the saddle outlet andmeter riser. Slip the protective sleeve over the outletend of the service saddle, and secure the protectivesleeve with plastic tape to avoid slippage of sleeveduring backfill operation.

To fuse a lateral line to a Branch Saddle (2" IPS outlet),socket fuse a coupling to the outlet, then socket fusethe lateral line to the coupling. Pressure test all fusionsafter required cooling time.

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Butt Fusion

You'll need these tools:

1. Place pipe and/or butt fitting ends into fusion ma-chine clamps. Ends should extend approximately aninch past alignment clamps for facing. With four-clamp

machines, the outer clamps should be securely tightenedto prevent pipe slippage. Inner clamps can be looser toallow easier high/low alignment adjustment. Check for

T .D. WILLIAMSON BUTT FUSION EQUIPMENT

McELROY BUTT FUSION EaulPMENT

Butt Fusion. ..Here's how. ..

Prior to placing pipe in the butt fusion equipment,remove any badly flattened, damaged or "neckeddown" ends with pipe cutting equipment. Clean endsto be joined with a clean dry cloth.

2. Insert facing unit. Close pipe (fitting) ends againstrotating facing blades and machine pipe (fitting) endsto smooth, flat surfaces. Long continuous shavings willindicate proper facing of pipe (fitting) ends. Operatefacer until machine has bottomed out against stopson facing unit.

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3. Separate pipe (fitting) ends and remove facer.POWERED FACERS MUST BE TURNED OFF BE-FORE REMOVAL. Check ends for full, complete facing.If facing is incomplete, repeat Steps 1 and 2.

4. Bring pipe (fitting) ends together and carefully checkalignment. Adjust high side down by tightening clamp.DO NOT LOOSEN LOW SIDE CLAMP. Repeat Steps2 and 3. In the case of coiled pipe, it may be neces-sary to rotate the pipe to accomplish alignment. If so,repeat Steps 1 through 4.

If pressure of the pipe against the heater is maintainedduring the heating period, melt will be squeezed awayfrom pipe ends, causing a concave effect in theheated pipe ends. This could result in a weakenedjoint after fusing.

6. Open pipe (fitting) ends and remove heater, beingcareful not to displace melt when removing heater.Manual machines may require quick snapping actionsto open the pipe ends and remove the heater.

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7. Bring pipe (fitting) ends together quickly (within 3seconds). Do not slam together as this may causeexcessive displacement of melt, resulting in a poorquality fusion. Use enough pressure to roll the meltswell beads over to the pipe (fittirlg) surface.** HOLDTHIS PRESSURE FOR THE COOLING CYCLE TIMEshown in Recommended Fusion Time Cycles chart onPage 19, or about 30 seconds per inch of pipe dia-meter. Each bead after fusion should be equivalent tothe following thicknesses (diameters):

5. Insert Heating Tool between ends. CLOSE ENDSAGAINST HEATER SURFACES STRONGL yENOUGH TO INSURE FULL CONT ACT, THENRELAX TO CONT ACT PRESSURE ONL y .*Hold pipe (fitting) ends in contact with heater untilheating cycle is complete. During the heating cycle,a bead of molten polyethylene will form and expand asthe polyethylene melts. Heat pipe (fitting) ends for thetime cycle shown in Recommended Fusion Time Cycleschart on Page 19, or until the Melt Swell Bead Width isthe size shown in the table below. Heating time startswhen a complete, uniform bead of molten material isvisible around the entire circumference of both ends.

Melt Swell Bead Width Guidelines

Pipe Size Bead Thickness

1-1/4" IPS to 2" IPS 1/16" to 1/8"3" IPS to 4" IPS 1/8"

6" IPS 3/16"8" IPS & Larger 3/16" to 1/4"

The double bead width should be about 2 to 2-1/2times its height, and uniform in size and shape allaround the joint.

Pipe Size Bead Width1-1/4" to 3" About 1/16"

3" to 6" 1 /16" to 1/8"6" to 8" 1/8" to 3/16"

8" & Larger 3/16" to 1/4"* 44OoF :t 1OoF and SOooF :t 1OoF are acceptable

heater face surface temperatures.~

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**Hydraulic machine fusion pressures may be deter-mined using the fusion interface pressures below:

Fusion Interface Pressure Guidelines

Heater Surface InterfaceTemperature Pressure

500°F :f: 10°F 80 :f: 15 psi440°F :f: 10°F 60 :f: 15 psi

Over-pressuring the melt will cause the bead to overlayitself and could result in a sub-quality fusion since themelt would be pushed to the O.D. and I.D. of thefusion, creating a possible "cold ring" in the centersection of the fusion. Under-pressuring could result ininadequate fusion due to insufficient contact in themelt area. Also, extreme care should be exercised notto reduce pressure during fusion cooling even if thebead exceeds the desired width. Reversing the pres-sure will cause porosity in the fused area.

8. The fused joint may be very carefully removed fromthe equipment following an additional three minutescooling time.

9. AFTER REMOVAL FROM FUSION EQUIPMENTALLOW AN ADDITIONAL 10 TO 60 MINUTES cooL-ING TIME BEFORE ROUGH HANDLING OR TES~ING (longer times for larger sizes).

10. If the steps outlined in this technique were followedcarefully, an acceptable joint should have been made.

11. Consult PLEXCO Bulletin No.105, "QualificationProcedures for Making PE 2406 Polyethylene HeatFusion Joints," or PLEXCO Bulletin No.106,"Qualification Procedures for Making PE 3408YELLOWSTRIPE@ Polyethylene Heat Fusion Joints"for techniques used to evaluate the quality of the joint.

12. Clean heater faces, being careful not to damagecoated surfaces-use wooded implement and clean,dry, lint-free non-synthetic rags. Do not use metalimplements to clean heater faces.

NOTE: Butt fusion machines from different manufactur-ers or different designs from the same manufacturermay require different gauge pressures to obtain properinterfacial pressure for fusion. It is recommended thatfusion conditions be established for each of the variousdesigns of fusion machines to be used. On requestPLEXCO will provide guidelines for torque requirementson selected manually operated McElroy and RidgidP&S, butt fusion equipment, and pressure gauge set-tings for selected McElroy; Ridgid P&S, and Christiehydraulically operated butt fusion equipment.

CAUTION:In sections where a fitting is present, the bendingradius should be limited to 120 to 125 times the pipediameter: Polyethylene pipe without fittings can bepermanently bent to a radius 20 to 25 times the pipediameter without damage or effect on its physicalproperties.

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When fusing in cold weather conditions, the time re-quired to form the proper melt will vary. For Socketand Saddle Fusions, a few trial melt patterns should bemade on the pipe under field conditions to establishthe required melt time. Increase the standard melt-timecycles by 5-second intervals until the proper time isestablished. Avoid time cycles in excess of that requiredto get a good melt pattern. After establishing theproper cold weather melt-time cycle, begin the fusionoperation by placing the female face on the pipe, startcounting the established cold-weather time cycle. Thesocket fitting should then be pushed on the male face.

Although it may take several seconds to fully engagethe fitting on the male face, there should be no problemin obtaining a melt in the fitting since the fit will be snug atthe outset. After removal of Heating Tool, melted sur-faces should be quickly checked and immediatelyjoined (within 3 seconds) to avoid cooling of themelted surfaces. Continue with the remaining steps inthe procedure to complete the fusion.

When applying a saddle-type fitting, first place theheating tool on the main, then place the saddle baseon the tool and apply the necessary pressure to obtaincomplete contact of the pipe and saddle with the heat-ing tool surfaces. Heat for the previously determinedcold-weather time cycles if the saddle fittings arestored inside the heated cab of the service vehicle; itmay be necessary to briefly preheat the pipe with theheating iron before placing the fitting onto the iron.

BUTT FUSION: The time required to form the initialmelt bead will automatically extend the total melt timecycle. After the melt forms, follow the standard buttfusion time cycle.

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First remove all frost, ice, or snow from O.D. and I.D.surfaces of areas to be fused. This should be done bylightly tapping or scraping the solids until they flake offthe pipe ends. Wipe dry with clean white paper towelsor rags. Shield areas to be fused with wind break orcover. Ice or snow should also be removed from areaswhere cold ring clamps will be applied.

In cold weather, pipe diameters and socket fittingentrances will normally contract. Keep fittings in cab oftruck, thus reducing exposure to extremely low temp-eratures. This will reduce contraction, making it easierto place socket fittings on heater faces.

When performing socket fusions, the Cold Ring Clampwill fit loosely on the pipe end. Place a backup ColdRing Clamp behind the loose cold ring which is in thenormal position behind the Depth Gauge. The backupclamp should be shimmed with tape to prevent slippage.The loose Cold Ring Clamp will allow the pipe to ex-pand to the proper O.D. as it is heated.

It is recommended that only electrically heated toolsbe used (plugged into their power source), since thesurface temperature of gas-heated tools cannot bemaintained long enough to produce the proper melt.If gas-fired tools are used, they should be near 525°Fwhen removed from the heat source to compensate forheat loss. TO OBTAIN PROPER MELT PATTERNS,INCREASE MELT TIME CYCLES-DO NOT INCREASETEMPERATURE OR PRESSURE OF PIPE AND/ORFITTINGS ON HEATING TOOL FACES.

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Section 4. The polyethylene pipe materials presentlyon the market can be joined to one another pro-vided the proper technique is used for the specificmaterials and the type of joint. The important para-meters are time of heating and temperature of thefusion tool for butt and socket joints. The pressureused to join the fused parts is also important for buttfusion. Ambient conditions should also be taken intoconsideration.

PLEXCO recommends that the above criteria shouldbe paramount considerations when joining differentpolyethylenes. However, DIFFERENT POLyETHYL-ENES SHOUlD NOT BE MIXED INDISCRIMINATElV-optimum conditions will be achieved when joining pipeand fittings from the same manufacturer's system.

For more information regarding fusion of materialsfrom different manufacturers, see PPI Technical NotesTN-13 1 181 "General Guidelines for the Heat Fusion ofUnlike Polyethylene Pipes and Fittings."

On request, PLEXCO will provide additional informationand technical assistance in proper fusion proceduresfor joining the PLEXCO system with polyethylenesystems of other manufactures and material designations.

CAUTION:In sections where a fitting is present, the bendingradius should be limited to 120 to 125 times the pipediametel: Polyethylene pipe without fittings can bepermanently bent to a radius 20 to 25 times the pipediameter without damage or effect on its physicalproperties.

Fusi ng PLEXCO@Products with OtherTypes of Pipes:Industry studies indicate that polyethylene of differenttrade names and/or different polyethylenes, such as2306, 2406, 3406, and 3408 materials, can be success-fully joined by heat fusion.

MELT TIMES PRESCRIBED AT 500°F BY EACHMANUFACTURER FOR HIS PRODUCT SHOULDBE USED. Apply the Heating Tool first to the materialrequiring the longest melt time. Then apply the prod-uct requiring the lesser melt time to the heater so themelt cycle for both products will be completed at thesame time. All other fusion conditions and proceduresremain the same as when joining PLEXCO products.

The Plastics Pipe Institute has established a set of"Criteria for Joining Various Polyethylene Materials toOne Another by Heat Fusion Techniques," StatementE, April 3, 1974. Of particular importance applicable tothe PLEXCO System would be the following:

Section 1. All pipes and fittings should meet theestablished applicable standards of the AmericanSociety for Testing and Materials.

Section 2. PE joints made by heat fusion tech-niques should only be made by properly trainedpersonnel whose competency has been determinedby adequate testing. The equipment used to makeheat fusion joints should also be checked at intervalsto assure that it is in proper operating condition.

Section 3. Polyethylene pipe and fittings made fromthe same commercial designation of polyethyleneproduced at different plants, and formed by differentextrusion and injection molding machines, can bejoined by the same procedure provided the prod-ucts meet the current ASTM component standards.

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COOLING TIME CYCLES specified are the minimumtimes that the pipe and/or fitting must be held firmly inplace. At least 3 minutes additional cooling time isrequired before removing the fused joint from theequipment. Light handling or making an additionalfusion on the same fitting may be performed after this

cooling period.

CAUTION: An additional 10 to 60 minute coolingtime {depending upon procedure and pipe size) isrequired after removing the joint from the fusionequipment before testing or subjecting the jointto bending, burying, pressure testing, or similarhandling and backfill stresses.

The heater iron temperature of 5OOoF :t 1OoF isbased on construction crews using the same fusionirons for socket, saddle and butt fusion. However, ifthe heater iron is used exclusively for butt fusion, thena temperature of 44OoF :t 1OoF can be used.

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Heating iron temperature and heating times are forideal field conditions at temperatures ranging from55°F to 85°F and no wind. As ambient temperaturesand wind conditions change, heating times must bealtered-see cold weather operating instructions.

A crayon temperature indicator or pyrometer shouldbe used daily to check the tool surface temperatureagainst the tool thermometer. ALL HEATING TOOLTEMPERATURES ARE THE TEMPERATURES ONTHE SURFACE OF THE TOOL FACE THATACTUALLY CONTACTS THE PIPE OR FITTING.There will usually be a significant temperaturedifference between the tool faces and the toolthermometer, with the faces being cooler. Therefore,the thermometer reading will need to be higher thanthe recommended heating tool face temperatures. Insome cases, especially saddle fusion, the surfacetemperature on one face may vary significantly fromthat on the other face. In this case, the lowertemperature surface should be at the recommended

temperature.

HEATING TIME CYCLES start as follows:

Socket Fusions- Time starts after fitting and pipeare fully inserted on heater faces.

Saddle Fusions (Tapping Tee, Service Saddle,Branch Saddle)- Time starts after fitting and pipeare tightly seated against heater faces.

The following times apply when using smoothheater faces. If serrated heater faces are to beused, reduce heating time by approximatelyfive (5) seconds.

Butt Fusion- Time starts after a bead of moltenmaterial is first visible around the complete circum-ference of both pipe and/or fitting ends.

Chevron@

HeaterFace Temp.

SOO°F

HeaterFace Temp.

500°FHeating Cooling

Time Time

(seconds) (seconds)6-7 206-7 209-10 20

10-12 206-7 208-10 20

10-12 3012-14 3014-17 3016-19 3020-24 4024-28 40

40 (Fitting) 6025 (pipe)*40 6040 6040 6040 6040 60

50-60 12070-80 18070-80 18080-90 18080-90 180

440°F 500°F

Heating Heating CoolingPipe Time Time TimeSize (sec.) (sec.) (sec.)

1/2" CTS 12-14 6-7 40t 3/4" CTS 14-17 8-10 40

1" CTS 16-19 10-12 401-1/4" CTS 18-22 12-14 401/2" IPS 14-17 8-10 40

I I 3/4" IPS 16-19 10-12 401" IPS 18-22 12-14 401-1/4" IPS 25-30 14-17 601-1/2" IPS 35-42 15-18 602" IPS 40-48 16-19 603" IPS 50-60 20-24 754" IPS 55-66 24-29 906" IPS 90-108 40-48 180~" IPS and Larger-Use Sight Fusion Procedure

*Use heat shield on pipe surface for first 15 secondsof this time cycle.

tSocket fusion recommended for these sizes.

Heating CoolingTime Time

(seconds) (seconds)9-10 309-10 30

14-16 3014-16 30

9-10 3012-14 3015-17 4018-21 4020-23 4024-28 4028-32 5032-37 50

45 (Fitting) 7030 (pipe)*50 7050 7050 7050 7050 70

55-65 15075-90 18075-90 18085-100 18085-100 180

440°F 500°F

Heating Heating CoolingPipe Time Time TimeSize (sec.) (sec.) (sec.)

I t 1/2" CTS 15-18 6-7 50

t 3/4" CTS 16-19 8-10 50t 1" CTS 18-22 14-17 50t 1-1/4" CTS 20-24 16-19 50t 1/2" IPS 16-19 8-10 50t 3/4" IPS 18-22 14-17 50t 1" IPS 20-24 16-19 50

1-1/4" IPS 35-42 18-22 701-1/2" IPS 50-60 26-31 902" IPS 55-66 28-34 903" IPS 65-78 30-36 1204" IPS 75-90 35-42 1206" IPS 105-126 55-66 1808" IPS and Larger-Use Sight Fusion Procedure

*Use heat shield on pipe surface for first 15 secondsof this time cycle.

tSocket fusion recommended for these sizes.

PipeSize

1/2" CTS3/4" CTS1" CTS1-1/4"CTS1 /2" IPS3/4" IPS1" IPS1-1/4"IPS1-1/2" IPS2" IPS3" IPS4" IPS

1-1/4"IPS

Socket Socket

PipeSize

1/2" CTS3/4" CTS1" CTS1-1/4" CTS1/2" IPS3/4" IPS1" IPS1-1/4" IPS1-1/2" IPS2" IPS3" IPS4" IPS

1-1/4"IPSStandard

TappingTee& .

ServiceSaddle

Standard

TappingTee& .

ServiceSaddle

2" IPS3" IPS4" IPS6" IPS8" IPS

2" IPS3" IPS4" IPS6" IPS8" IPS

2" IPS

3" IPS

4" IPS

6" IPS

8" IPS

2" IPS

3" IPS

4" IPS

6" IPS

8" IPS

HVTT&

BranchSaddle

HVTT&

BranchSaddle

Butt Butt

19

PLEXCO PE 3408 YELLOWSTRIPE@ ORPLEXCO PE 2406 POLYETHYLENE PLEXCO EHMW PE 3408

POLYETHYLENE