{"product_id":"internal-pipe-repair-coupling-40mm-50mm-class-9-class-12","title":"Internal PVC Pipe Repair Coupling - 40mm (1.5\") \u0026 50mm (2\") - Class 9 \u0026 Class 12 - Pool \u0026 Spa Pressure Pipe","description":"\u003c!-- HASP-FLP-1.0 | SKU 1533938 \/ 1536854 \/ 1533939 \/ 1536855 | rule PIPE-1.0 | canary: internal-joiner-echo --\u003e\n\u003ch3\u003eInternal PVC Pipe Repair Coupling - 40mm (1.5\") \u0026amp; 50mm (2\") - Class 9 \u0026amp; Class 12\u003c\/h3\u003e\n\u003cp\u003eAn internal repair coupling for PVC pressure pipe. Unlike an ordinary coupling, this one glues \u003cstrong\u003einside\u003c\/strong\u003e the two pipe ends rather than over them, so the repair adds nothing to the outside diameter of the pipe.\u003c\/p\u003e\n\u003cp\u003eThat is the whole point of the fitting. It is the repair for a cut or cracked pipe you cannot pull apart: pipe cast into a slab, run through a wall, buried hard against something, or sitting tight behind equipment.\u003c\/p\u003e\n\u003ch3\u003eGet The Class Right Or It Will Not Fit\u003c\/h3\u003e\n\u003cp\u003eThis is the part people get wrong. Because the coupling seats inside the pipe, what matters is the pipe's \u003cstrong\u003einternal\u003c\/strong\u003e diameter, and the internal diameter changes with the pressure class. Same 40mm pipe, different class, different bore.\u003c\/p\u003e\n\u003cp\u003eAustralian PVC pressure pipe to AS\/NZS 1477 is sized by its \u003cstrong\u003eoutside\u003c\/strong\u003e diameter, which stays the same across every class. The class sets the wall thickness, and the thicker the wall the smaller the bore. So a Class 12 pipe has a noticeably tighter bore than a Class 9 pipe of the same nominal size, and the couplings are not interchangeable.\u003c\/p\u003e\n\u003ctable style=\"width: 100%;\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eNominal size\u003c\/th\u003e\n\u003cth\u003eImperial name\u003c\/th\u003e\n\u003cth\u003ePipe OD\u003c\/th\u003e\n\u003cth\u003eClass\u003c\/th\u003e\n\u003cth\u003eWall thickness\u003c\/th\u003e\n\u003cth\u003ePipe ID (mean)\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e40mm\u003c\/td\u003e\n\u003ctd\u003e1.5\"\u003c\/td\u003e\n\u003ctd\u003e48.1 to 48.4mm\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eClass 9\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1.90 to 2.30mm\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003e44.05mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e40mm\u003c\/td\u003e\n\u003ctd\u003e1.5\"\u003c\/td\u003e\n\u003ctd\u003e48.1 to 48.4mm\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eClass 12\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e2.50 to 3.00mm\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003e42.75mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e50mm\u003c\/td\u003e\n\u003ctd\u003e2\"\u003c\/td\u003e\n\u003ctd\u003e60.2 to 60.5mm\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eClass 9\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e2.40 to 2.80mm\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003e55.15mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e50mm\u003c\/td\u003e\n\u003ctd\u003e2\"\u003c\/td\u003e\n\u003ctd\u003e60.2 to 60.5mm\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eClass 12\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e3.10 to 3.60mm\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003e53.65mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003eDimensions are from the AS\/NZS 1477 Series 1 PVC-U pressure pipe tables and agree with the published Vinidex and Iplex pipe data.\u003c\/p\u003e\n\u003ch3\u003eHow To Tell Which Class You Have\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eRead the pipe.\u003c\/strong\u003e Pressure pipe is printed along its length with the standard and the class, as \"AS\/NZS 1477\" and \"PN9\", \"Class 9\", \"PN12\" or \"Class 12\". This is the reliable method. Wipe the pipe down and look, including on the offcut you just removed.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMeasure the wall.\u003c\/strong\u003e Once the pipe is cut you can measure the wall thickness on the cut face with vernier calipers. On 40mm, roughly 2mm is Class 9 and roughly 2.8mm is Class 12. On 50mm, roughly 2.6mm is Class 9 and roughly 3.3mm is Class 12. The gap between the classes is large enough to call with confidence.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMeasure the bore.\u003c\/strong\u003e Compare against the ID column above. Measure across the cut end, not down a socket.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eNot sure after all that? \u003ca href=\"mailto:shop@hasp.com.au\"\u003eSend us a photo\u003c\/a\u003e of the pipe print and the cut end with a tape or calipers across it, and we will tell you which one you need.\u003c\/p\u003e\n\u003ch3\u003eWhat These Do Not Suit\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDWV pipe.\u003c\/strong\u003e Waste pipe to AS\/NZS 1260 is a different size system, with different outside and inside diameters, and it carries no pressure class. If the print says AS\/NZS 1260, or there is no class marked at all, this is not the fitting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClass 6 and Class 18 pressure pipe.\u003c\/strong\u003e 40mm and 50mm pipe is also made in Class 6, which has a wider bore, and Class 18, which has a much tighter one. Neither variant here will make a sound solvent weld in those.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFlexible spa pipe.\u003c\/strong\u003e \u003ca href=\"\/products\/50mm-2-flexible-pvc-pipe-for-spas-63mm-od\"\u003eSpaFlex\u003c\/a\u003e and similar flexible PVC have their own bore and need a fitting made for them.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImperial schedule pipe.\u003c\/strong\u003e US Schedule 40 and Schedule 80 share some outside diameters with the metric range but not the bores.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eInternal Or External Coupling\u003c\/h3\u003e\n\u003cp\u003eUse an ordinary external coupling wherever you can. It is cheaper, the joint is visible, and it is more forgiving to glue. An internal coupling earns its place only when the pipe cannot move.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePipe ends can be sprung apart, or one run can be pulled back:\u003c\/strong\u003e use a standard coupling, such as our \u003ca href=\"\/products\/50mm-coupling-joiner-pvc\"\u003e50mm PVC coupling joiner\u003c\/a\u003e.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNeither end will move, or there is no clearance around the pipe:\u003c\/strong\u003e use the internal coupling on this page.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eYou have room to cut out a section and want flexibility:\u003c\/strong\u003e a length of \u003ca href=\"\/products\/40mm-1-5-flexible-pvc-pipe-for-spas-xxmm-od\"\u003e40mm\u003c\/a\u003e or \u003ca href=\"\/products\/50mm-2-flexible-pvc-pipe-for-spas-63mm-od\"\u003e50mm flexible pipe\u003c\/a\u003e with couplings is often the easier repair.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFitting\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003eIsolate the pump and drain the line. Solvent cement will not take on a wet surface and a joint made on a pressurised line will fail.\u003c\/li\u003e\n\u003cli\u003eCut the damaged section out square. In a tight spot a \u003ca href=\"\/products\/pvc-wire-saw-flexible-cable-saw-for-plastics\"\u003ePVC wire saw\u003c\/a\u003e will cut pipe where no cutter or hacksaw will reach.\u003c\/li\u003e\n\u003cli\u003eDeburr both pipe ends inside and out, and clean the inside of each end back far enough to take half the coupling. The inside of the pipe is the gluing surface here, so it has to be clean and dry.\u003c\/li\u003e\n\u003cli\u003eDry-fit first. The coupling should push in firmly by hand. If it drops in loosely you have the wrong class, and if it will not start you have the other wrong class. Do not force it and do not sand it to fit.\u003c\/li\u003e\n\u003cli\u003eApply \u003ca href=\"\/products\/747-ips-weld-on-pool-r-spa-glue-118ml-blue\"\u003esolvent cement\u003c\/a\u003e to the coupling and to the inside of the pipe, then push home with a slight twist and hold for 30 seconds. Work quickly, because you get one attempt.\u003c\/li\u003e\n\u003cli\u003eKeep the cement off the far end of the coupling. Excess inside the bore has nowhere to go and can end up carried into the pump or filter.\u003c\/li\u003e\n\u003cli\u003eIf your coupling has a centre stop, each pipe end butts against it, so set the gap between the pipe ends accordingly. If it has no stop, slide it fully into one end first, bring the pipes together, then draw it back to centre.\u003c\/li\u003e\n\u003cli\u003eLet the joint cure before you pressurise it. Follow the cure time on the cement for the pipe size and the day's temperature, and leave it longer in the cold.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003eAn internal joint cannot be inspected once it is made and cannot be cut out and redone without losing more pipe. If the repair is on a buried line or anywhere a leak would be expensive to find again, this is work for an experienced hand.\u003c\/p\u003e\n\u003ch3\u003eChoosing Your Variant\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e40mm Class 9\u003c\/strong\u003e suits 40mm pressure pipe with a 44.05mm bore\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e40mm Class 12\u003c\/strong\u003e suits 40mm pressure pipe with a 42.75mm bore\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e50mm Class 9\u003c\/strong\u003e suits 50mm pressure pipe with a 55.15mm bore\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e50mm Class 12\u003c\/strong\u003e suits 50mm pressure pipe with a 53.65mm bore\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eYou Will Probably Also Need\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/747-ips-weld-on-pool-r-spa-glue-118ml-blue\"\u003e747 PVC solvent cement, 118mL\u003c\/a\u003e or the \u003ca href=\"\/products\/747-ips-weld-on-pool-r-spa-glue-473ml-blue\"\u003e473mL tin\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/pvc-wire-saw-flexible-cable-saw-for-plastics\"\u003ePVC wire saw, for cutting pipe in tight spots\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/50mm-coupling-joiner-pvc\"\u003e50mm PVC coupling joiner, the standard external coupling\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eWhy does the class matter on an internal coupling?\u003c\/strong\u003e\u003cbr\u003eBecause the coupling seals against the inside of the pipe. Pressure pipe keeps the same outside diameter across all classes and changes its wall thickness instead, so the bore is different in every class. A 40mm Class 9 pipe has a 44.05mm bore and a 40mm Class 12 pipe has a 42.75mm bore, a difference of more than a millimetre.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow do I find the class of my pipe?\u003c\/strong\u003e\u003cbr\u003eIt is printed along the pipe with the standard, as \"PN9\" or \"Class 9\". If the print has worn off, measure the wall thickness on the cut face. On 40mm pipe Class 9 is about 2mm and Class 12 about 2.8mm.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill this fit 40mm or 50mm DWV waste pipe?\u003c\/strong\u003e\u003cbr\u003eNo. DWV pipe is made to a different standard with different diameters. Pool and spa plumbing is pressure pipe, not DWV.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I use an internal coupling instead of a normal one?\u003c\/strong\u003e\u003cbr\u003eYou can, but there is no reason to. A standard external coupling is cheaper and easier to glue. The internal coupling exists for repairs where the pipe cannot be sprung apart or there is no room around it.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat if my pipe is Class 6 or Class 18?\u003c\/strong\u003e\u003cbr\u003eNeither of these will fit. Contact us with the pipe size and class and we will tell you what the options are.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDo I need primer as well as cement?\u003c\/strong\u003e\u003cbr\u003eClean, dry, deburred surfaces matter more than anything else on this joint. Use the solvent cement according to its own instructions, and remember the inside of the pipe is the surface being welded, so it needs the same preparation you would give a socket.\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003eCommon search terms: internal pipe repair coupling, internal pipe joiner, PVC internal coupling 40mm, PVC internal coupling 50mm, class 9 internal joiner, class 12 repair coupling, pool pipe repair coupling, slab pipe repair, repair cut PVC pipe no movement, internal joiner with stop.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eBefore ordering:\u003c\/strong\u003e confirm both the pipe size and the pipe class. These are not interchangeable and an internal coupling cannot be adjusted to fit. If you are unsure, seek professional assistance or \u003ca href=\"mailto:shop@hasp.com.au\"\u003econtact us\u003c\/a\u003e with photos of the pipe print and the cut end. As with all products, this must be diagnosed and fitted by a qualified and experienced person.\u003c\/p\u003e\n\u003c!-- HASP-FLP-1.0 end | canary: internal-joiner-echo --\u003e","brand":"Heater and Spa Parts","offers":[{"title":"40mm \/ Class 9","offer_id":68187802697917,"sku":"1533938","price":28.0,"currency_code":"AUD","in_stock":true},{"title":"40mm \/ Class 12","offer_id":68187802730685,"sku":"1536854","price":39.0,"currency_code":"AUD","in_stock":true},{"title":"50mm \/ Class 9","offer_id":68187802763453,"sku":"1533939","price":30.0,"currency_code":"AUD","in_stock":true},{"title":"50mm \/ Class 12","offer_id":68187802796221,"sku":"1536855","price":28.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0372\/5253\/files\/internal-pvc-pipe-repair-coupling-40mm-1-5-50mm-2-class-9-12-pool-spa-pressure-plumbing-fittings-720.webp?v=1794175565","url":"https:\/\/hasp.com.au\/products\/internal-pipe-repair-coupling-40mm-50mm-class-9-class-12","provider":"Heater and Spa Parts","version":"1.0","type":"link"}