Bead & Crevice Free Machines
The BCF Jointing System provides beadless, crevice-free joints for GEORGE FISCHER'S PVDF and polypropylene natural piping system in sizes 20mm (½") through 63mm (2").
Achieve unsurpassed fusion weld quality:
- No beads;
- No crevices;
- No transitions;
- No dead legs and no microorganic deposits;
- Very high fusion weld stability;
- Very little stress in the fusion zone, therefore less prone to stress cracking corrosion;
- Dimensions d20–d63 mm.
Used where there is extreme concern about the presence of small beads or crevices in the piping system: Ultrapure and Hot Ultrapure Water are the lifeblood of semiconductor and photovoltaic equipment processing. SYGEF® Plus systems out of PVDF high purity material with the corresponding IR Plus® fusion technology offers the industrial benchmark solution. Pure water of WFI (water for injection) also requires the light purity piping system as offered by the Bead and Crevice Free system.
Plastic pipe dimensions are, by convention, specified by the outside diameter, usually denoted by e. This may be supplemented by stating the nominal inside diameter or DN. Sometimes the pipe wall thickness is specified by the SDR or Standard Dimension Ratio.
SDR = d divided by e.
Where d = the outside diameter (mm)
Where e = the pipe wall thickness (mm)
The pipe size can be calculated as follows:
di = 18.8 √Q1 ÷ v
di = Inside pipe diameter (mm)
Q1 = Flowrate in m3/h
v = Flow velocity, usually 0.5 to 1.0 m/s for suction lines
1.0 to 3.0 m/s for discharge lines.
Material α = mm/mK ABS 0.10 PE 0.15-0.20 PP 0.16-0.18 PVC-U 0.07-0.08 PVC-C 0.06-0.07 PVDF 0.12-0.18
A rough calculation of pressure loss in straight length plastic pipe can be done using,
Δ Pr = λ × (L ÷ di) × (ρ ÷ 2.102) × v2
Δ Pr = Pressure loss (bar)
λ = Pipe friction factor
L = Length of straight pipe (m)
di = Inside pipe diameter
ρ = Liquid density (kg/m3)
v = Flow velocity (m/s)
For smooth bore plastic pipe: λ = 0.02