SKU VT-58578 (90° solvent-weld elbow) · family of 10 solvent-weld and threaded PVC pressure references

1. Technical specifications

Solvent-weld socket — schedule 40 tapered socket dimensions (ASTM D2466-13, Table 1 · NTC 1339)

A and B diameters are averages with tolerances of ±0.10 mm (±0.004 in) in 1/2″–3/4″ up to ±0.28 mm (±0.011 in) in 6″; C is the minimum depth measured from the entrance face to the socket bottom (zero negative tolerance). The socket is tapered: the entrance diameter A is larger than the bottom diameter B, so the pipe (OD 21.34 mm in 1/2″; 60.32 mm in 2″) makes interference before reaching the bottom — that interference is what compresses the solvent-cement film and seals the joint. E is the minimum socket wall (equal to the minimum sch 40 pipe wall) and F the fitting body wall (125 % of the sch 40 pipe wall, para. 6.1.3 of D2466). Values concordant with Charlotte Pipe submittal FO-SUB-PVC-40.

Minimum center-to-socket-bottom dimensions (ASTM D2466-13, Table 2)

These are the standard's MINIMUM values for 90° elbows, 45° elbows, tees and couplings: each manufacturer's actual laying length is equal or greater and is confirmed on quotation. Total assembly length of a figure = center-to-bottom distance + socket depth C at each opening. For bushings and adapters the standard additionally requires that no point of the spigot fall below the minimum pipe OD (para. 6.1.2).

Material and standard requirements

Compound	Rigid PVC, cell class 12454 per ASTM D1784 (designation PVC 1120, Type I): the same compound as the catalog's pressure pipe — the digit-by-digit reading of the cell class (impact, tensile ≥ 48.3 MPa, modulus ≥ 2,758 MPa, deflection ≥ 70 °C) lives in the PVC pressure pipe data sheet and is not repeated here.
Minimum wall thicknesses	Body: 125 % of the minimum wall of same-size sch 40 pipe · socket: at least the minimum sch 40 pipe wall · threaded portion: at least the thickness under the thread root of same-size sch 80 pipe (D2466-13, para. 6.1.3).
Waterway	The fitting's minimum inside diameter may not be less than the minimum ID of the corresponding sch 40 pipe (para. 6.1.4): a standard-compliant fitting does not choke the line (14.68 mm in 1/2″; 51.33 mm in 2″; 152.04 mm in 6″).
Threads	60° taper threads per ASTM F1498 (the NPT profile applied to thermoplastics, gaged per F1498 itself) on the male adapter, female adapter and threaded cap.
Minimum burst (quality control)	ASTM D1599 test (60–70 s): 1,910 psi at 1/2″ · 890 psi at 2″ · 560 psi at 6″ for the 12454 compound (D2466-13, Table 4) — equal to the burst of sch 40 pipe; the MPa table Colombian manufacturers publish under NTC 1339 matches value for value. It is NOT a service pressure: see section 2.

General specifications

Product	Family of injection-molded PVC pressure fittings: schedule 40 solvent-weld socket plus threaded versions — 10 references.
Figures	90° elbow, 45° elbow, tee, bushing, coupling, union, solvent-weld cap, threaded cap, male adapter and female adapter.
Size range	1/2″ to 6″ per figure (union and threaded cap up to 4″; 6″ on request in several figures — confirmed on quotation).
Joining system	Solvent welding (NTC 576:2021 solvent cement + ASTM F656 primer) between the fitting socket and the plain end of the catalog's SDR-series PVC pressure pipe (NTC 382); threaded references with F1498 taper threads.
Working pressure	60 % of the working pressure of same-size sch 40 pipe, with water at 23 °C — full table, rule and temperature derating in section 2.
Applicable standards	NTC 1339 (PVC schedule 40 fittings; based on ASTM D2466-13) · ASTM D1784 (compound) · ASTM F1498 (threads) · NTC 576:2021 / ASTM D2564 (solvent cement) · ASTM F656 (primer) · ANSI/NSF 61 (potable water).
Normative marking	Manufacturer's mark · material designation (PVC 1) · size · standard designation · seal of the laboratory certifying potable-water suitability (D2466-13, sec. 10; suppl. S1).

2. Fitting working pressure: the 60 % rule

The most expensive confusion in pressure PVC: the molded fitting does NOT inherit the pipe's working pressure. NTC 1339 / ASTM D2466 only set dimensions and a minimum BURST pressure equal to that of sch 40 pipe — and the standard itself clarifies (para. 6.3.2) that those burst pressures are a quality indicator and do not imply working pressures. The physical reason: PVC's hydrostatic design basis (HDB = 4,000 psi, ASTM D2837) is measured on extruded PIPE; the injection-molded fitting adds stress concentration at direction changes, mold weld lines and the socket root, and has no HDB of its own. The documented industry practice — Ron D. Bliesner, "Operating and Maintaining Piping Systems Using PVC Fittings" (1987), expressly adopted by the standard's manufacturers (Westlake, LASCO, Boshart) — rates the molded sch 40 and sch 80 fitting at 60 % of the working pressure of same-schedule, same-size pipe:

Working pressure by size — water at 23 °C, non-shock

Sch 40 pipe pressures per the tables published by Westlake (FT-PS-001) and LASCO for non-shock water at 23 °C (73 °F); fitting column = exactly 60 % of the pipe column (Bliesner rule). Unlike the SDR series, in schedule 40 the rating FALLS as the size grows (with the exception of 2-1/2″, whose diameter-to-wall ratio is more favorable than 2″'s). Burst pressures are minimums of the 60–70 second D1599 test: they are neither service nor test pressures.

Temperature derating — factors over the 23 °C pressure

Service temperature		Factor	Resulting 2″ elbow/tee
°C	°F		psi	bar
23 °C	73 °F	1.00	168	11.6
27 °C	80 °F	0.88	148	10.2
32 °C	90 °F	0.75	126	8.7
38 °C	100 °F	0.62	104	7.2
43 °C	110 °F	0.51	86	5.9
49 °C	120 °F	0.40	67	4.6
54 °C	130 °F	0.31	52	3.6
60 °C	140 °F	0.22	37	2.6

Factors published by Westlake and LASCO for PVC (the same material factors used for pipe, with minimal rounding differences versus the Uni-Bell series in the pipe data sheet: 0.51 vs 0.50 at 43 °C). 60 °C (140 °F) is PVC's maximum operating temperature; the standard's manufacturers additionally do not recommend threaded PVC connections above 43 °C (see section 4).

Crossing with the catalog's pipe: from 1-1/2″ up, the fitting governs

The catalog's PVC pressure pipe is SDR 21: a constant 200 psi (13.8 bar) from 3/4″ to 6″ — the basis of that figure (SDR formula, HDS, pipe derating) lives in data sheet FT-TC-TUB-PVC-001 and is not repeated here. Crossing both tables yields the system's real map: in 1/2″–1-1/4″ the fitting (360–222 psi) exceeds the pipe and the pipe governs; from 1-1/2″ up the fitting falls below the pipe's 200 psi (198 psi at 1-1/2″, 168 at 2″, 132 at 4″, 108 at 6″) and the fitting governs: in a 6″ SDR 21 line, the molded elbow leaves the system's real capacity at little more than half the pipe's.

Exception to the 60 % rule: "special engineered" fittings (unions, flanges, valves — ASTM F1970) carry their own manufacturer-established working pressure, typically lower than the pipe's; the catalog union's rating is confirmed on quotation.

3. Solvent-cemented joint step by step (NTC 576)

Solvent cement does not glue: it cold-welds. The cement (certified to NTC 576:2021, based on ASTM D2564) dissolves the surfaces of the pipe end and the socket; as the solvent evaporates both fuse into a single piece. On the tapered socket of section 1, the interference compresses the cement film — which is why a properly made joint is stronger than the pipe itself (as the national manufacturer's manual states). The procedure, per NTC 576 and the Pavco Wavin technical manual (Feb 2020 ed.):

1. Cut and dry fit	Cut the pipe square and deburr. Test pipe and fitting without cement: the pipe must enter snug, never loose — if loose, change the pipe or the fitting. The socket taper stops the pipe before the bottom: that is the interference zone that will seal the joint.
2. Cleaning	Clean the pipe end and the socket with primer/cleaner (ASTM F656) even if they look clean. Never join wet surfaces or work under rain. The NTC 576 seal covers the cement; the primer is specified per F656.
3. Application	Generous cement on the pipe and a light coat in the socket, with a natural-bristle brush (not nylon) as wide as half the pipe diameter. Excess inside the socket stays active in the bore and weakens the pipe wall.
4. Insertion	Insert fully at once, turning 1/4 turn to spread the cement (ASTM D2855 practice), and hold for a few seconds: the taper tends to push the pipe back out. The whole operation, from application to assembly, in under 1 minute.
5. Verification	A properly made joint shows a continuous cement bead around the entire socket perimeter — do not remove it: it is the evidence of full coverage.
6. Curing	1 hour before moving the line and 24 hours before subjecting it to test pressure (Pavco Wavin manual for PVC). Large diameters, low temperature and high humidity extend the times: the cement manufacturer's cure table governs.

Cement takeoff: one quart yields ≈760 simple 1/2″ joints and ≈30 of 6″ (Pavco Wavin yield table) — consumption per joint grows about 25-fold across the range. PVC and CPVC cements are not interchangeable. Never test or convey compressed air or gases in the system: failure of a gas-pressurized thermoplastic is explosive fragmentation (warning in D2466 para. 1.2 and from manufacturers); line testing is always hydrostatic, with water.

4. Threading on PVC and transition to metal

The family's three threaded references (male adapter, female adapter and threaded cap) carry 60° taper threads per ASTM F1498 — the same NPT profile of the metallic world, applied to thermoplastics — and are the bridge between the cemented network and threaded equipment: valves, meters, faucets and metallic runs. The standard protects the threaded zone by design: the threaded portion's wall must be at least that of the material under the thread root of same-size sch 80 pipe (D2466-13, para. 6.1.3).

The metal-transition rule: PVC male into metallic female, never the reverse

A taper thread seals by wedging: as it tightens, the male expands the female. When the female is metallic and the male is the PVC adapter, the metal (steel's elastic modulus is ~70 times that of cell-class 12454 PVC) contains the wedge without deforming and the more elastic plastic conforms and seals. In the opposite direction — metallic male inside a PVC female — the metal acts as an undeformable wedge and leaves the plastic female in permanent hoop tension: the part cracks, sometimes weeks after assembly. That is why the correct transition is always the PVC male adapter threaded into the metallic female, and the PVC female is reserved for receiving plastic males.

Tightening	Hand-tight plus 1 to 2 wrench turns (installation guidance of the standard's manufacturers). Over-tightening is the number 1 failure mode of the plastic thread: it gains no seal, it gains cracks.
Sealant	PTFE tape (2–3 wraps in the thread direction) or a sealant certified as PVC-compatible. Sealants with solvents aggressive to PVC are prohibited: they attack the thread root.
Temperature	The standard's manufacturers (Westlake, LASCO) do not recommend conventional threaded PVC connections above 43 °C (110 °F): at that temperature use cemented joints and, where disassembly is required, a union or flange.
Disassembly	Threaded cap = removable access (drains, future test points); solvent-weld cap = permanent closure. The union allows removing equipment without cutting the line (manufacturer's own rating, ASTM F1970 — confirmed on quotation).

SDR-series pipe is never threaded: threading removes wall from an already-minimum thickness and voids the pipe's pressure classification (rule from the PVC pressure pipe data sheet). Every threaded transition is made with these molded adapters, whose threaded zone does have the reinforced thickness the standard requires.

5. Frequently asked questions

Does a PVC pressure elbow take the same pressure as the pipe?

No: the molded schedule 40 fitting is rated at 60 % of the working pressure of same-size sch 40 pipe — a 2″ elbow works at 168 psi (11.6 bar) at 23 °C, versus 280 psi for sch 40 pipe and 200 psi for the catalog's SDR 21 pipe. From 1-1/2″ up the fitting falls below the SDR 21 pipe and governs the line's pressure (section 2). What the fitting does match is the BURST pressure of the quality test (D2466, Table 4), which is not a service pressure.

Why doesn't the manufacturer's catalog publish the fitting's pressure?

Because NTC 1339 / ASTM D2466 establish no working pressure for the fitting — only dimensions and minimum burst — and most manufacturers answer with the PIPE's data sheet. The fitting's service rating comes from the documented 60 % industry practice (Bliesner, 1987), expressly adopted by Westlake, LASCO and Boshart; the full table by size is in section 2 of this sheet.

How long do I wait after cementing before pressurizing the line?

24 hours before the hydrostatic test and 1 hour before even moving the pipe (Pavco Wavin manual; NTC 576 cement). Large diameters, cold weather or high humidity extend those times: the cement manufacturer's cure table governs. Testing is always with water — never with compressed air.

How do I connect the PVC network to a threaded metallic valve or pipe?

With the PVC male adapter threaded into the metallic female, never a metallic male inside a PVC female: the metal acts as a wedge and cracks the plastic thread (section 4). Hand-tight plus 1–2 wrench turns with PTFE tape, and no PVC threads above 43 °C.

Are the threaded cap and the solvent-weld cap interchangeable?

Not in function: the solvent-weld cap closes permanently (it is cold-welded to the line) and the threaded one is removable — used as an access or future drain point on an adapter. In sizes, the threaded cap reaches 4″ and the solvent-weld cap 6″.

Can I use these fittings on sanitary (DWV) pipe?

No: the pressure line (NTC 1339, short tapered interference socket, rated cell class 12454 compound) and the sanitary line (NTC 1341) are different systems — the sanitary fitting is not pressure-rated and its sockets and walls differ. Each system joins with its own pipe and its own fitting family from the catalog.

6. Application notes

7. Technical notice and limitation of liability