¡¡¡¡¡¡¡¡¡¡¡¡Pipes
projects |
Rifeng
multiplayer pipes |
Rifeng
PEX pipes |
PPR
pipes
|
UPVC
pipes
|
Thermal coefficient
(w/m.K) |
0.45
|
0.41 |
0.24 |
|
| Thermal expansion ratio |
2.5¡Á10-5(almost
equal to
the value of aluminum) |
2.0¡Á10-4 |
1.8¡Á10-4 |
3.9¡Á10-5 |
| Packing |
coil
|
coil |
straight |
straight |
| Cutting |
easiest
|
easiest |
easy |
easy |
| Jointing type |
screw or press fitting |
screw or press fitting |
heat-fusion
|
adhesive with solvent |
| Installing |
easy |
easy |
difficult(need special
heat-fusion tools)
|
difficult(need special
solvent) |
| Operation condition |
Tmax=95¡æ
pressure:1Mpa |
Tmax=90¡æ
pressure:0.6Mpa |
Tmax=70¡æ
pressure:1Mpa |
Only for cold water |
Bending at room
temperature |
easy but no spring back
for small size pipe |
easy but spring back |
no bending |
no bending |
Low temperature
resistance |
excellent |
excellent |
bad |
bad |
| Stress crack resistance |
excellent |
excellent |
bad |
bad |
| Size stability |
high |
lower |
lower |
lower |
| Gas permeability |
0 |
little(need barrier
layer) |
little |
little |
| Chemical resistane |
excellent |
excellent |
good |
general |
| Heat-aging resistance |
good |
good |
bad |
bad |
| Hygiene |
excellent |
excellent |
excellent |
general
(need to add kinds of additives) |
Price(for small-diameter
pipes) |
high |
lowest |
lower |
lower |
| Application scope |
Petable water supply
system , compressed air pipeline, floor-heating
system etc. |
Cold-hot piping system
and floor-heating system etc. |
Cold-hot piping system
with lower temperature. |
Only used for drainage
system in general. |
