Flexible Systems
What is PEX-Flex?
PEX-Flex is a pre-insulated flexible pipe ideally suited for hydronic heating and district energy transfer. Supplied in coils (single or dual configuration), this pipe system is economical, simple to install and highly effective even in harsh soil conditions.
Technical Information
PEX-Flex
is flexible pre-insulated pipe designed for the
efficient transfer of hot or cold medium. Supplied
in single or dual (supply and return bundled
together) format coils, this seamless pipe system
is economical, simple to install and highly effective
even in harsh soil conditions.
PEX-Flex is “self-compensating” with
respect to expansion and contraction …
just uncoil and snake into trench, then backfill.
The pipe installs quickly and easily without
solvent welding, special tools or heavy equipment
resulting in a lower installed cost when compared
to other insulating methods. No drainage tile,
gravel fill or deep/wide trench required. PEX-Flex
can be shallow buried even in high water table
areas. The flexible nature of coiled PEX-Flex
all but eliminates the need for joints, elbows
and fittings making it a true seamless pipe system.
The PEX-Flex carrier pipe is made of plastic
cross linked polyethylene (PEX) with EVAL coating
which keeps oxygen from penetrating the pipe
wall. The PEX is surrounded by a factory applied
layer of closed cell, eco-friendly polyurethane
foam – the best insulation material on
the market. The whole package is encased in a
tough but flexible extruded polyethylene jacket
with UV stabilizer.
The pipe system is bonded … meaning
the carrier pipe(s), insulation and jacket are
mechanically linked to one another and move collectively
during expansion/contraction. This also isolates a moisture problem to damaged area should the jacket be punctured … water cannot migrate through entire pipe system.
All PEX-Flex pipe comes equipped with a “smart”
membrane between the outer casing and the insulation.
This leak proof diffusion barrier prevents (cyclopentane)
gas in the foam from escaping through the jacket
and being replaced by atmospheric air which has
inferior insulating properties – a process
called “aging”. This keeps the operating
performance high throughout the entire service
life of the pipe.
PEX-Flex is manufactured by Kingspan LOGSTOR of Denmark, the world’s largest producer
of pre-insulated pipe systems employing over
1400 people in 9 production facilities. Kingspan LOGSTOR
has over 30 years experience of pre-insulating
flexible PEX tubing. Urecon Ltd. distributes Kingspan LOGSTOR
products throughout Canada and the US.
Single PEX-Flex Dimensions
| Nominal pipe size |
Carrier pipe OD |
Carrier pipe ID |
Carrier pipe wall thickness |
Jacket pipe OD |
Standard/ Maximum coil lengths* |
Minimum bending radius |
Weight |
| in | in (mm) |
in (mm) |
in (mm) |
in (mm) |
ft (m) |
ft (m) |
lb/ft (kg/m) |
| ¾ | 0.98 (25) |
.784 (20) |
0.098 (2.5) |
3.0 (77) |
328/984 (100/300) |
2.6 (0.8) |
.70 (1.0) |
| 1 | 1.26 (32) |
1.032 (26.2) |
0.114 (2.9) |
3.0 (77) |
328/984 (100/300) |
2.6 (0.8) |
.70 (1.0) |
| 1¼ | 1.57 (40) |
1.28 (32.6) |
0.145 (3.7) |
3.5 (90) |
328/984 (100/300) |
3.0 (0.9) |
1.9 (1.3) |
| 1½ | 1.97 (50) |
1.608 (40.8) |
0.181 (4.6) |
4.3 (110) |
328/984 (100/300) |
3.5 (1.1) |
1.3 (1.9) |
| 2 | 2.48 (63) |
2.024 (51.4) |
0.228 (5.8) |
4.9 (125) |
328/656 (100/200) |
4.0 (1.2) |
1.6 (2.4) |
| 2½ | 2.95 (75) |
2.406 (61.2) |
0.272 (6.9) |
5.5 (140) |
328 (100) |
4.5 (1.4) |
2.2 (3.3) |
| 3 | 3.54 (90) |
2.894 (73.6) |
0.323 (8.2) |
6.3 (160) |
328 (100) |
5.2 (1.6) |
2.8 (4.2) |
| 4 | 4.33 (110) |
3.544 (90) |
0.393 (10.0) |
6.3 (160) |
328 (100) |
5.2 (1.6) |
3.7 (5.5) |
* Pipe can also be supplied to exact length required. Maximum lengths are special order
n.b.: All sizes are metric, not IPS nor CTS sizes; imperial adapters are supplied as required..
Dual PEX-Flex Dimensions
| Nominal pipe size |
Carrier pipe OD |
Carrier pipe ID |
Carrier pipe wall thickness |
Jacket pipe OD |
Standard/ Maximum coil lengths* |
Minimum bending radius |
Weight |
| in | in (mm) |
in (mm) |
in (mm) |
in (mm) |
ft (m) |
ft (m) |
lb/ft (kg/m) |
| 2 x ¾ | 2 x 0.98 (2 x 25) |
0.784 (20) |
0.098 (2.5) |
4.3 (110) |
328/ 656 (100/200) |
3.5 ( 1.1) |
1.4 (2.1) |
| 2 x 1 | 2 x 1.26 (2 x 32) |
1.032 (26.2) |
0.114 (2.9) |
4.3 (110) |
567/1,134 (173/246) |
3.5 (1.1) |
1.5 (2.2) |
| 2 x 1¼ | 2 x 1.57 (2 x 40) |
1.280 (32.6) |
0.145 (3.7) |
4.9 (125) |
328/ 656 (100/200) |
4.0 (1.2) |
1.8 (2.7) |
| 2 x 1 ½ | 2 x 1.97 (2 x 50) |
1.608 (40.8) |
0.181 (4.6) |
6.3 (160) |
328 (100) |
5.2 (1.6) |
2.8 (4.1) |
In bold is dual 1” PEX-Flex … most commonly used size for OWF applications (note the ID of the carrier pipe is 1.03” which is considerable larger than other ASTM pipes).
* Pipe can also be supplied to exact length required. Maximum lengths are special order.
n.b .: All core pipe sizes are metric; metric compression x imperial NPT threaded adaptors are supplied as required.
| Pipe size | Max. temperature | Max. pressure |
| in (mm) | Fahrenheit (Celsius) | P.S.I. (bar) |
| ¾ - 4 (20 - 110) | 203 (95)* | 87 (6) |
*Refer to detailed PEX-Flex product specification at www.pexflex.net for temperature and pressure considerations.
Other Applications
Millions of
feet of PEX-Flex have been installed in industrial,
commercial and residential hydronic related pipe
systems around the world. The pipe is used wherever
energy savings are required by keeping overall
heat losses (or gains) to a minimum. Typical
applications include ice/snow melt systems; chilled
water distribution; hot water district energy
projects; chemical feed; industrial process piping
and even solar heating.
Flexible steel
pipe (STEEL-Flex) is also available in coils
for projects requiring higher temperature thresholds.
See our Flexible Systems
brochure for more information.
Ice/Snow
Melt Systems
Use PEX-Flex to run warm water from the heat source to the pad without losing heat.
Chilled Water Distribution
Use PEX-Flex to distribute centrally chilled water for air conditioning … often without joints or fittings. The highly efficient polyurethane insulation reduces heat gain from the warm soil (or ambient air temperature) greatly increasing system efficiency.
Hot Water District Energy
Use PEX-Flex to move around hot water in campus style systems … often without joints or fittings. Also ideally suited for steam condensate return.
Chemical Feed / Industrial Process Piping
Use PEX-Flex for transfer of chemicals or general process piping. Typically, joints and fittings are eliminated reducing worry of leakage … saving money when compared to traditional containment piping.
