TECTULby IMR

Fluid conveyance · Polypropylene piping

TECHNICAL DATA SHEET

FT-TC-TUB-PPR-001

Issue date: July 22, 2026 · Rev. 001

PP-R socket-fusion polypropylene pipe PN16 (SDR 7.4 · pipe series S 3.2)

TECTUL · WhatsApp +573161111666 · Mon–Fri 8:00–17:00 · Sat 8:00–12:00 (GMT-5) · Dispatch across Colombia · Exports to Central & South America

VT-86950 · PN16 socket-fusion PP-R pipe, blue, 4 m lengths, 9 diameters 20–110 mm · price from COP $30,800 + VAT per length (Jul 2026, confirmed on quotation)

1. TECHNICAL SPECIFICATIONS

General specifications

Dimensions — series S 3.2 / SDR 7.4 (PN16)

¹ Minimum wall thicknesses from the S 3.2 column of ISO 15874-2:2013, Table 5 (dimension class A, ISO 4065 metric series); tolerances per Table 9 of the same standard. Nominal inside diameters per manufacturer dimension tables conforming to EN ISO 15874. The nominal size of PP-R is the actual outside diameter in millimetres: the inch label is trade shorthand only and does not allow interchanging fittings from other dimensional systems. The allowable pressure is the same for every diameter of the series (see engineering calculations): that is why this table carries no per-size pressure column.

PP-R material properties

2. ENGINEERING CALCULATIONS (PRESSURE – TEMPERATURE – SERVICE LIFE)

In a thermoplastic the allowable pressure is not a single number: it depends on water temperature and on the projected service life, because PP-R strength decays continuously along its regression curves (ISO 9080; equations (3) and (7) of ISO 15874-2:2013). PN16 does not mean 16 bar at every temperature: it is the trade label of the S 3.2 series referenced to water at 20 °C and 50 years. Every value used is declared below — nothing is silently assumed:

P = 2 · σ · e / (dn − e) = σ / S

Worked example — cold water at 20 °C, 50 years (ISO 15874-2)

1. Design stress at 20 °C/50 years: σ = 6.93 MPa (ISO 15874-2:2013, Table A.2, PP-R; includes C = 1.4 from Table A.1).
2. PN16 pipe series: S = 3.2.
3. P = σ / S = 6.93 / 3.2 = 2.17 MPa ≈ 21.7 bar ≈ 315 psi.
4. Check with a real diameter (dn 25, e 3.5): S = (25 − 3.5)/(2 × 3.5) = 3.07 ≤ 3.2 → the trade series stays on the safe side.

The ISO result (21.7 bar) and the DIN 8077 table with a 1.5 coefficient (20.4 bar) bracket the same fact: at 20 °C the PN16 pipe withstands more than its nominal 16 bar; the PN label is conservative only in cold service. In hot service the opposite happens, as the next table shows.

Allowable pressure by temperature and service life — series S 3.2 / SDR 7.4 (manufacturer table per DIN 8077, safety coefficient 1.5, water)

Additional references from the same table: 5.1 bar (74 psi) at 80 °C/25 years and 4.1 bar (59 psi) at 95 °C/5 years. The accelerated drop at 70 °C/50 years happens because the projection crosses the knee of the regression curve (second branch, equation (7) of ISO 15874-2:2013). Engineering reading: between 20 °C and 70 °C, at 50 years, PN16 loses 67% of its capacity (from 20.4 to 6.7 bar).

Maximum design pressure by application class — ISO 15874-2:2013, Table 3 (S 3.2)

¹ Highest standardized design pressure (options in the standard: 4, 6, 8 or 10 bar) whose maximum calculated S (Table 3 of ISO 15874-2:2013) admits the S 3.2 series; per-class design stress per Table A.2 (which includes each class temperature profile via Miner's rule, ISO 13760, and the coefficients of Table A.1). For cold water the standard caps its options at 10 bar even though the calculation with σ = 6.93 MPa yields 21.7 bar.

3. SOCKET FUSION — PARAMETERS BY DIAMETER (DVS 2207-11)

The standard PP-R joint up to 63–75 mm is socket fusion: the heating tool simultaneously melts the pipe outside and the fitting inside at 260 ±10 °C (500 ±18 °F) per DVS 2207-11. Heating time is counted from the moment pipe and fitting reach the insertion depth — not before —, the joint is made without twisting the parts, and alignment can only be corrected during the joining time. Parameters from the system manufacturer's fusion manual, conforming to DVS 2207-11:

Execution rules: square, burr-free cut; mark the insertion depth before heating; insert without twisting; under-heating yields an incomplete bond and over-heating restricts the bore; from 75 mm a bench machine is required; larger system diameters (from 160 mm) are joined by butt fusion. Verify the actual plate temperature with a contact thermometer before the first joint. The exact times and depths of the tool in use override this table: confirm them in the fusion machine manual.

4. THERMAL EXPANSION AND SUPPORT SPACING

The coefficient of linear thermal expansion of single-layer PP-R is α = 0.15 mm/m·°C (compound datasheet), about 13 times that of carbon steel (≈11.7×10⁻⁶ K⁻¹, ASM Handbook). In hot-water runs the pipe grows visibly and the installation must absorb that movement with direction changes, flexible arms or expansion loops — never by rigidly anchoring both ends.

ΔL = α · L · ΔT

1. Example: L = 10 m (33 ft) hot-water riser installed at 20 °C operating at 60 °C: ΔT = 40 °C (72 °F).
2. ΔL = 0.15 × 10 × 40 = 60 mm (2.4 in) of run growth.
3. Flexible arm absorbing that ΔL at a direction change: LB = C · √(dn · ΔL), with C the PP-R constant published by the system manufacturer (PPR system catalogues publish values between 15 and 30).
4. With the most conservative constant (C = 30), dn 32 mm: LB = 30 × √(32 × 60) = 30 × 43.8 ≈ 1,315 mm (≈4.3 ft) of free arm before the first anchor.

The expansion loop (4 × 90° bends) works as a double sliding arm: its length is twice the calculated arm. Supports: fixed points at every direction change and intermediate sliding points that allow axial travel; metal clamps always rubber-lined so they do not score the pipe. Maximum horizontal support spacing per manufacturer catalogue for SDR 6-7.4 pipe (vertical runs allow 30% more): dn 20: 60 cm at 20 °C and 40 cm at 70 °C; dn 32: 80 → 55 cm; dn 63: 130 → 85 cm; dn 90: 165 → 110 cm. PP-R demands much closer supports than metal pipe, and the spacing shrinks as temperature rises. The TECTUL catalogue includes the socket-fusion polypropylene compensation pipe (prefabricated omega loop) to resolve expansion in long straight runs.

5. SANITARY AND FLUID COMPATIBILITY

The scope of ISO 15874 (and of its Colombian adoption NTC 4897) covers hot and cold water installations within buildings, whether or not the water is intended for human consumption. PP-R is a polyolefin: it undergoes no electrochemical corrosion, needs no coatings and adds no corrosion products to the water — manufacturer catalogues expressly state that it preserves the potability of the conveyed water. The sanitary fitness of each batch compound is certified by its manufacturer under the applicable national regulation (ISO 15874-1 defers to each country's rules; in Colombia, the drinking-water quality criteria of Resolución 2115 of 2007): that certificate is supplied on quotation.

• Hydraulic roughness: smooth bore (roughness on the order of 0.007 mm per compound datasheet), with no corrosion scaling over the service life.
• UV radiation: PP-R degrades under prolonged sun exposure; store under roof, in stacks of 1.5 m maximum, and protect exposed runs (manufacturer recommendation).
• Fluids other than water: system manufacturers list compressed air and polyolefin-compatible fluids; the pressures in this datasheet are derived for water — for any other fluid, validate chemical compatibility and the pressure criterion with our technical team.
• Freezing and cold weather: do not install or fuse with water present in the line; below +5 °C ambient the fusion heating times increase (table in section 3).

6. TECHNICAL Q&A

Does PN16 mean the pipe withstands 16 bar?

Not at every temperature: 16 bar is the trade label of the S 3.2 series referenced to water at 20 °C and 50 years. The DIN 8077 table with a 1.5 coefficient gives 20.4 bar at 20 °C/50 years, but only 6.7 bar at 70 °C/50 years: temperature, not diameter, defines the allowable pressure.

Does PN16 PP-R work for hot water?

Only at low pressure: at 70 °C/50 years it retains 6.7 bar allowable, and by ISO 15874 application class the S 3.2 series admits at most 8 bar in class 1 (DHW 60 °C) and 6 bar in class 2 (DHW 70 °C). For domestic hot water the design practice is PN20 (SDR 6), available on request.

Does it work for compressed air?

It is used in compressed-air networks and system manufacturers list it as an application; the pressures in this datasheet are derived for water, so for air apply the system manufacturer's criterion and consult our technical team before setting the working pressure.

Why is PP-R ordered in millimetres and not inches?

Because its nominal size is the actual outside diameter: a 25 mm pipe measures 25.0 mm. The inch label (3/4″ for 25 mm) is trade equivalence only; connection to NPT threads uses metal-insert transition fittings, never a thread cut into the pipe.

7. Application notes

8. Technical notice and limitation of liability