Socket fusion welding of polypropylene - IPS Flow Systems

1 IpsInstallers and installation equipmentInstallation personnel should be trained and technically competent for this jointing method. Training for installers isavailable free of charge on request from our technical tools required for the job should be assembled and checked prior to commencing any work. When assemblinglonger runs or large size polypropylene pipes, the use of guides, pipe rollers or supports, is recommended to reducethe drag forces work crew should be equipped with equipment to enable safe handling of the pipes on site, together withappropriate hand tools. In addition, it is recommended that the following tools are used during the jointing tools designed specifically for plastic piping Systems greatly improves the performance of the installation teamand reduces the risk of bad joints being addition to everyday pipe fitters tools the installation of polypropylene piping requires a fusion - welding machine ofthe appropriate size and type.

2 Care should be taken to consider the advantages and disadvantages of each jointingmethod prior to commencement on site. In some cases, a combination of welding methods may prove to be the mostcost-effective solution. Our technical department can advise on suitable jointing of the Requirements for Machines and Equipment Used for fusion Jointing Thermoplastics can be found in DVS2208 Instructions Part fusion welding of polypropyleneInstalling plastic pipesPipe CuttingItemPipe DiameterPart NumberRotary Cutter6 - 63mm 04124 Rotary Cutter10 - 90mm 04134 Rotary Cutter48 - 114mm 04144 SawUp To 75mm04512 SawUp To 100mm04510 SawUp To 150mm04517 IPS Flow Systems l Seaham Grange Industrial Estate l Seaham l SR7 0PT l England l Tel: 0191 521 3111 l cutting and preparationBefore cutting, pipes should be conditioned to reach the ambient working temperature under which installation andjointing will take place.

3 Pipe should always be cut to length using tools specifically designed for use with plastic pipe. A rotary pipe cutterwith the correct blade or wheel appropriate for the pipe wall thickness is recommended, as they provide a highdegree of accuracy in the finished cutting length, and also produce a square cut to the pipe. Power tools such as bandsaws, or circular saws may also be used - however they should have blades that are specifically designed for use withplastic pipe. Handsaws with blades suitable for use with plastic pipe may be used, however it is recommended that amitre box be used to ensure a square cut is achieved. Once the cutting process is completed, the pipe length should be checked for accuracy, and any internal or externalburrs should be removed using a deburing tool specifically designed for use with plastic pipe.

4 Any plastic chips orswarf should also be removed from the inside of the pipe. The jointing area of the parts to be welded must be freefrom damage or installation of polypropylene piping Systems makes use of so-called Z dimension of the fitting. An explanationof the use of the Z dimension is shown in the following example:-Explanation:M = Distance mid-mid fittingL = Cutting length of pipeZ = Z-dimension of fittingThe Z dimension for polypropylene pipe fittings that is used to calculate pipe cutting lengths can be found in thedetailed dimensional fusion welding of polypropylenePreparation of the work areaAssemble the welding equipment according to the manufacturers instructions, with due provision for safe workingpractices. When working outdoors, the area used for jointing must be protected from rain, snow and wind.

5 Thepreferred ambient working temperature for welding is in the range of +5 C to +45 C. Protecting the fusion weldingarea with a tent or similar device can help maintain an even temperature in the work area. Installing plastic pipesL (Cutting Length of Pipe)M (Distance Mid-Mid Fitting)ZZIPS Flow Systems l Seaham Grange Industrial Estate l Seaham l SR7 0PT l England l Tel: 0191 521 3111 l fusion welding of polypropyleneMaking a Socket fusion joint - introductionIn Socket fusion jointing, pipes and fittings are lap-welded together as the male pipe end is inserted into the femalesocket of the fitting. This process does not require any consumables, as the parts to be joined are heated to weldingtemperature using a single fusion tool with heating bush and heating spigot. The pipe and fitting dimensions, as wellas those of the heating tools, are in accordance with strict tolerances so that when joining force is applied afterheating, a homogenous joint will result.

6 The welding method is documented in DVS 2207 Part 11 - plastic pipesCalibration of Peeling ToolsPipe Diameter (d)Calibration Length (L)(mm)(mm)(mm) element Socket fusion welding may be performed using hand held tools on pipe outside diameters of up to63mm, but for larger sizes the use of a bench mounted welding device is recommended. It is preferred, if possible, touse a bench mounted welding machine for all pipe sizes, as these devices greatly improve the joint alignment. For successful jointing, the pipe ends must be calibrated by means of a peeling and chamfering tool. At the sametime, it removes the oxidised layer that forms naturally on the outside surface of the pipe. This oxidised layer canhave a detrimental effect upon the final joint strength, and it is essential that it be removed prior to welding .

7 The toolalso produces a bevel on the leading edge of the pipe, which aids entry into the Socket fusion fitting during thewelding calibration diameter and correct length for the peeling of the pipe ends is shown in the following table:Hand-held socketfusion tool with optional bench mountingBench Socket fusion tool suitable for workshop or site useIPS Flow Systems l Seaham Grange Industrial Estate l Seaham l SR7 0PT l England l Tel: 0191 521 3111 l fusion welding of polypropyleneMaking A Socket fusion Joint - Joint Preparation21 Before heating, thoroughly inspect the heating bushesfor signs of damage or contamination Clean carefullywith non-fraying paper or a clean cloth, and ifnecessary replace any unacceptable parts. Connect thetools to a reliable power source and switch the welding temperature on the fusion -weldingtool to 250 C-270 C.

8 Prior to each weld verify thetemperature using a digital thermometer with surfacesensor, or with tempil sticks (253 C for lowtemperature and 274 C for high temperature).6 Remove the internal burr from the pipe, and clean upany cutting debris or using a bench mounted Socket fusion machine, fitthe pipe and the fitting into the clamps on themachine. Bring the parts together and check that theyare aligned and chamfer the pipe end using a calibrated tooldescribed above. Avoid touching the cleaned andprepared the pipe ends squarely using tool suitable forplastic pipe. A wheel-type cutter is ideal. If a saw isused, a mitre box is recommended to ensure a squarecut. Power saws may be used with plastic pipesPeeling the pipePositioning fitting in clampIPS Flow Systems l Seaham Grange Industrial Estate l Seaham l SR7 0PT l England l Tel: 0191 521 3111 l the heating element and draw the pipe andfitting onto the heating bushes.

9 If using a hand heldheating element, do not twist the parts. Hold thisposition for the duration of the heating time shown inthe table the end of the heating period simultaneouslyremove the pipe and fitting from the heating insert the pipe into the Socket until thepipe reaches the bottom of the fitting Socket (this iscontrolled mechanically with a bench mounted fusionmachine). Take care to align the pipe and the joint in position without movement for theduration of the cooling period shown in the table completed, inspect the joint for any visible signs ofdefects or contamination. A correctly made joint will havethe appearance of twin parallel weld beads at the outsideof the joint. The weld beads should be similar in size, andbe complete around the circumference of the joint.

10 Socket fusion welding of polypropyleneMaking a Socket fusion joint - completing the jointHeating, adjusting and cooling times for polypropylene Socket fusion jointsPipe SizeHeating TimeAdjusting TimeCooling (mm)(sec)(sec)Fixed (sec) Total (min)16546220546225741023286104401262045 0186204632483067530830690408406110501050 8 Installing plastic pipesThe heater is removed and the parts are brought togetherCooling the completed joint before handlingHeating the pipe and fitting1112Do not pressurise the joint for a minimum of 1 Flow Systems l Seaham Grange Industrial Estate l Seaham l SR7 0PT l England l Tel: 0191 521 3111 l