PPR Fittings Names List: What to Write So the Right Part Ships

Open any PP-R manufacturer’s catalogue and you will find a short cylindrical fitting that joins two pipes of the same diameter. One catalogue calls it a socket. The next calls it a coupling. A third calls it a coupler. They are the same part. What makes this more than a vocabulary problem is that the disagreement is not only between suppliers — it happens inside a single published catalogue. IFAN ULTRA’s own live product list sells that fitting twice, once as PPR Coupling and once as PPR Socket 139/M78.

So the usual advice — “learn the standard names” — fails immediately, because for commercial PP-R fittings there is no naming authority to learn. ISO 15874-3, the international standard that governs PP fittings for hot and cold water, classifies fittings by the joint they make: socket fusion, electrofusion, mechanical, and fittings with incorporated inserts. It does not publish a schedule of trade names. What follows is the working list, the part-number logic that identifies a fitting when its name does not, and the reason the drawing symbol you are hunting for probably does not exist.

Why One Fitting Has Three Names

The naming disagreement survives because nothing has ever forced it to resolve. Pipe threads have an issuing body. Nominal sizes have one. The commercial names printed on a fittings box do not. Each manufacturer inherited its vocabulary from whichever engineering tradition its first product line came from, and once a name is printed on ten years of packaging and quoted on ten years of purchase orders, changing it costs more than living with it.

You can watch this happen inside one catalogue. IFAN ULTRA publishes 95 products on its live store. Among them are both a “PPR Coupling” and a “PPR Socket 139/M78” — the same straight joint between two equal pipes. It also publishes both a “PPR Reducing Coupling” and a “Reduce Socket 139/M78”. The two families even carry different part-number prefixes, so a buyer comparing two quotations from the same supplier can be looking at two references for one physical part and have no textual clue that they match.

The same shapes appear in every PP-R catalogue. The names attached to them do not.

What the standard actually standardises

ISO 15874-3 is the part of the PP piping standard that covers fittings, and its current edition is ISO 15874-3:2013, carrying Amendment 1:2018 and Amendment 2:2021. A successor is in development but is not yet published, so 2013-plus-amendments is what a supplier should be citing today. The standard sorts fittings into four classes by the joint they form — socket fusion, electrofusion, mechanical, and fittings with incorporated inserts — and specifies how each must perform. It does not tell anyone what to call them.

This is the useful reframe. When two catalogues disagree about a name, they are not disagreeing about anything the standard covers, so neither is wrong. What both catalogues must agree on is the joint class, the size designation and the pressure rating — and those are specified. Argue about those; ignore the noun. If you want the full family-by-family breakdown of how those four classes map onto real products, our guide to PPR fitting types walks each one in turn.

PPR Fitting Names and What Each One Does

The table below is the reconciliation list. Every row was read off IFAN ULTRA’s live product pages on 28 August 2026, so the size ranges are what is actually published rather than what a generic industry list assumes. Print it, or keep the tab open next to the quotation you are checking — this is the web version of the list, not a download, and there is deliberately no PDF behind it.

Read the prefix, not just the noun

The prefix column is the part of the table that does real work. A supplier can call the straight joint anything at all, but a coupling in this catalogue starts 1040 and an elbow starts 1080, so the identity survives the vocabulary. The full ten-digit number then encodes the size: the DN20 coupling is 1040020911 and the DN20 tee is 1060020900, with the size sitting in digits four to six. Quote that number back in your enquiry and the naming argument disappears.

Two caveats keep this from being a rule you can apply blindly. First, the electrofusion coupling shares the 1040 prefix with the plain coupling — sensible, since both are couplings, but it means the prefix identifies the family and not the joining method.

Second, the catalogue contains at least one genuine mismatch: the entry named “PPR Cross-ove” publishes part numbers beginning 1090, which is the valve prefix, while “A Green PPR Cross” publishes 1040 numbers for what appears to be the same class of part. We are reporting that as an observation, not diagnosing it. The practical response is the same either way — confirm the part number against the size row you actually want rather than trusting the prefix alone.

The Drawing Symbol You Are Looking For Probably Does Not Exist

People searching for fitting names with diagrams are usually holding two documents: a supplier’s catalogue and an isometric drawing. They want the symbol on the drawing to map onto a name in the catalogue. It is a reasonable expectation and, for PP-R, it is mostly unavailable — and the reason is worth knowing before you spend another hour looking.

The relevant international standard is ISO 4067-1, “Technical drawings — Installations — Part 1: Graphical symbols for plumbing, heating, ventilation and ducting”, first edition dated 15 October 1984 and developed by ISO/TC 10. Its clause 4.1 covers pipework and pipework accessories. Read the actual list of what it contains:

• Pipework, general symbol — with variants for visible, hidden, and in front of or above the section plane
• Crossing of pipes without connection
• Crossing of pipes with connection, and the tee
• Flexible pipe or hose
• Direction of flow, and direction of gravity flow
• Sliding joint, general symbol
• Plug, sliding support, fixed point

There is no elbow. There is no coupling. There is no reducer, no union and no end cap. Clause 4.2, headed “Assemblages” — joints — is even shorter: a general joint symbol, a flange, a spigot-and-socket, and a sleeve. That is the complete set. A PP-R socket-fusion joint, the single most common connection in any PP-R system, has no symbol of its own and is drawn with the general joint symbol or borrowed spigot-and-socket mark.

Why the standard delegates identity to text

This is not an oversight. Clause 3 of the same standard sets out the method: a group of components is represented by a general symbol, and that symbol is then completed either by method A, designations and text, or by method B, complementary graphical additions. The standard is explicit that choosing one method excludes the other on the same drawing. In other words, the standard’s own design assumes the fitting will be identified by what is written next to it.

The practical consequence is the one that matters for procurement. If you are handed a PP-R isometric and asked to price it, the symbols will tell you the topology — where the run turns, where it branches, where it is valved — and the schedule text will tell you what to buy. When the schedule says “elbow” and the drawing shows a corner, the corner is not the evidence; the word is.

This also means house symbol conventions are legitimate and common: many consultants draw a filled quarter-circle for a 90° bend because no ISO symbol prevents them. Ask for the drawing’s own legend before assuming any symbol means what it means on the last project.

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Names identify the part; testing shows how the range performs: IFAN Full Series PPR Performance Tests.

Size Designations That Look Like Names But Are Not

A catalogue line reads “PPR Elbow 90° 1¼” — 40 mm, PN20, SDR6″. Four of those tokens look like one description. They are four independent facts, and confusing them is a more expensive error than calling a coupling a socket, because it ships the wrong part rather than merely confusing a conversation.

DN is a label, not a measurement

ISO 6708:1995 defines DN, the nominal size, as an alphanumeric designation used for reference purposes: the letters DN followed by a dimensionless whole number that is only indirectly related to the physical size in millimetres of the bore or of the outside diameter of the end connections. Dimensionless is the operative word. DN is a filing label, and the standard says so.

For PP-R this matters more than for most materials, because PP-R is designated on outside diameter while a steel DN refers to a nominal bore. A DN50 PP-R fitting and a DN50 steel fitting are not the same waterway, and a transition drawn as a straight size-for-size joint on a mixed-material riser is where that assumption gets discovered. Our PPR pipe sizes reference carries the outside-diameter and wall figures if you need to check a specific pairing.

The inch label is a trade size

Every size row in the IFAN ULTRA catalogue pairs a millimetre figure with an inch figure, and read across the whole 95-product list the pairing is consistent: 20 mm is ½”, 25 mm is ¾”, 32 mm is 1″, 40 mm is 1¼”, 50 mm is 1½”, 63 mm is 2″, 75 mm is 2½”, 90 mm is 3″, 110 mm is 3½”, 125 mm is 4″, 160 mm is 6″.

Notice 110 mm. Its published outside diameter is 4.33 inches, and the catalogue calls it 3½”. The inch column is a nominal trade size inherited from threaded-pipe convention, not a conversion of the millimetre figure. Order by millimetres, or by part number, and treat the inch column as a cross-reference only.

SDR is the token that changes what arrives

The reducing coupling is the clearest case of a size designation carrying information a name cannot. On the live product page the same nominal reduction — 160 to 110 mm — is published four times, once per standard dimension ratio: SDR 17.6 is 2047160001, SDR 11 is 1044160954, SDR 9 is 1043160122, SDR 7.4 is 1042160953. Four rows, one name, one identical pair of diameters, four different parts, separated only by wall thickness — the field an enquiry written off a drawing almost never carries.

An enquiry that says “reducing coupling, 160 to 110” is not an order; it is a question the supplier has to come back on, and every round trip costs a day. The full pressure-class and SDR framework is set out in the ISO 15874 and DIN 8077 explainer.

Threads, Inserts and the Designations That Date a Catalogue

Threaded transitions are where PP-R meets brass, steel and everything the fusion iron cannot touch, and they are the fittings where a name carries the least information. “Female threaded elbow, 1 inch” describes at least four different orderable parts.

The union with brass nut, part-number family 1050, published 32–75 mm.

The same SKU, two thread systems

IFAN ULTRA’s transition elbow page publishes two separate part-number columns for what the catalogue treats as one product: a zero-lead potable brass version carrying NPT designations, and a stainless-steel version carrying ISO designations. Both are current, both are orderable, and the choice is set per SKU and per destination market rather than by a single house standard. So the answer to “do you supply NPT or BSP” is genuinely “both, and you have to say which” — the thread system is a field on the order, not an attribute of the brand.

A designation that dates the document

That same product is titled with a DIN 2999 thread designation, and DIN 2999 is withdrawn. DIN 2999-1:1983-07 was superseded by DIN EN 10226-1:2004-10, with the supersession taking effect on 1 October 2004; the designations that replaced it are R for the taper external thread and Rp for the parallel internal thread.

The part is not obsolete — the reference is. Seeing DIN 2999 on a live page tells you the catalogue text predates a change made two decades ago, which is a reason to confirm the thread form explicitly rather than a reason to reject the supplier. We flag it here because a naming guide that repeated the designation without noting its status would be passing the problem on.

Ask for the certificate number, not the logo

One more documentation habit worth carrying into any fittings enquiry, and it applies to this supplier as much as any other. IFAN ULTRA’s Global Series page states that its PP-R pipes and fittings are DVGW and NSF certified, while the site’s certification listing records ISO 9001, SAI Global, SKZ, HY and NSF — with no DVGW entry.

We are not going to resolve that inconsistency from the outside, and we are not going to pick the flattering reading. The correct buyer behaviour is the same wherever you source: ask for the certificate number, the issuing body and the scope it covers, and check the scope names the fitting range you are buying rather than the pipe alone.

Writing the Name So the Right Part Ships

Everything above collapses into one practical rule: a fitting name is an index entry, not a specification. Five fields make a line unambiguous, and any supplier anywhere can fill an order written this way without a clarification email.

• Function, not vocabulary — “straight joint, equal diameters” beats socket, coupling or coupler, and survives translation into any catalogue.
• Size in millimetres — the outside diameter, because the inch column is a trade size and 110 mm is printed as 3½”.
• Pressure class or SDR — mandatory on reducers, wise everywhere. Without it, the four 160 to 110 mm parts (2047160001, 1044160954, 1043160122, 1042160953) are indistinguishable.
• Joint type — socket fusion, electrofusion, threaded or flanged. This is the axis ISO 15874-3 actually classifies on, so every supplier understands it.
• Thread designation where one exists — R or Rp under DIN EN 10226, or the NPT designation, stated explicitly rather than inferred from the region you are writing from.

A worked enquiry line

Suppose you need the straight joint at 63 mm, a 90° turn at 110 mm, and the reduction from 160 mm to 110 mm on a riser rated PN20. Written as names alone — “socket, elbow, reducer” — that is three ambiguous lines.

Written properly it is three unambiguous ones: “straight coupling, socket fusion, 63 mm, PN20 — ref 1040063916”; “elbow 90°, socket fusion, 110 mm, PN20 — ref 1080110-series, confirm suffix”; “reducing coupling, 160 to 110 mm, state SDR — supplier to confirm the SDR, since that reduction spans four part numbers (2047, 1044, 1043, 1042), one per SDR class”. Note the third line does not pretend to know the answer. It names the ambiguity and hands the supplier the one decision only they can close, which is what turns a quotation round trip into a single reply.

What you can and cannot pin down before you write

Some commercial terms are published and some are not, and knowing which is which saves an email. Minimum order runs at one full container load, with less-than-container shipment possible at a higher per-metre cost. The lead time is 15–25 days of production for one container before ocean transit, on 30% deposit and 70% before shipment. What is not published, and cannot honestly be quoted from a table, is the MOQ against a specific fittings mix — a first order weighted toward 110 mm elbows cubes out very differently from one weighted toward DN20 couplings, so that figure is set per project against your size list.

Before a first order settles, ask for a sample of the specific fittings you are unsure about and verify each one against the part number on its own product page. The printed marking on the part should reconcile to the certificate numbers you were sent. Checking that on a handful of pieces is cheaper than discovering a naming mismatch on a full container. For how many of each line to put on that list in the first place, our opening stock range for PPR fittings works through the quantities.

Conclusion

The trade-off in PP-R fitting names is that the vocabulary is genuinely unstandardised and the underlying facts genuinely are not. You cannot fix the first — no authority names commercial fittings, the disagreement predates every catalogue in your inbox, and even a single supplier’s own list can carry one part under two names. You can sidestep it entirely with the second, because joint class, outside diameter in millimetres, pressure class or SDR, and the thread designation are all specified, all published, and all unambiguous across every supplier you will deal with.

If you take one thing from the list above, make it the part number, and if you take two, make the second the habit of naming the ambiguity instead of guessing at it. The reducing-coupling line that says “state SDR” gets a usable quotation. The one that says “reducer, 160 to 110” gets a phone call. Anyone assembling a first fittings order who wants the shapes as well as the words will find the fitting-type breakdown the natural next read, and the PP-R Global Series range the place to check a name against real products.

Frequently Asked Questions