HYDAC FILTER SYSTEMS TCU Series, Инструкция по эксплуатации и техническому обслуживанию

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TransformerCare Unit Installing the TCU
Notes on piping / hosing
Install the suction line in such a way that there is an excess pressure level of at least
0.1 bar at the connection (5) of the TCU. This guarantees that the pump (2) cannot
absorb air via the shaft seal due to the primary pressure.
Protect the hoses against damage. Lay hoses which are routed along the ground in
a plastic pipe. Secure the hoses with guide rails.
Nominal line diameters for the suction line of DN20 (¾“) are generally sufficient for
lines up to ~ 15 meters in length. For suction lines longer than 15 meters, we
recommend nominal diameters of DN25 (1“). When operating at 60Hz, the suction
lines should generally be used with DN25 (1“) and limited to 20 meters.
For the return lines, DN20 (3/8) up to 20 meters is sufficient.
The pressure at the connection (5) of the TCU depends on the height difference
between the connection (5) and the fluid surface in the expansion vessel
(

P(height)) and the line losses (

P(line)).
As the TCU suction connection is below the fluid surface in the expansion vessel,
the pressure can be estimated as follows:
P = 1 bar + P(height) - P(line)
 
You can calculate the P(height) as follows:


P(height)[bar] = h[meters]/10[meters/bar].
h is the height difference between the suction connection on the TCU and the fluid
surface in the expansion vessel.
The pressure loss in the suction line (

P(line)) depends on:

Flow rate

Kinematic viscosity

pipe dimensions

fluid density
The pressure loss in straight round pipes (

P(line)) in a laminar flow can be
calculated as follows from this:
Δ p ~ 6,8 * Q * ν * D * L / d
4
Δ
p = Pressure differential in [bar]
Q = Flow rate [l/min] ~ 6 l/min
v = Kinematic viscosity [mm²/s]
D = Density [kg/dm³]
L
= Line length [m]
d = Internal line diameter [mm]
HYDAC FILTER SYSTEMS GMBH en Page 23 / 64
BeWa TCU 3472805b en 2011-07-05.doc 2011-07-05