Johnson Pump TG GS2-25 - Isolating Valves; Strainer; Secondary Piping; Drain Lines

33
Be
Ba
Bk
de
Be
Bk
Bn
Ba
de
Bb
A.0500.501 – IM-TGGS/05.01 EN (03/2013)
3.18.6.3 Isolating valves
To allow proper maintenance it is necessary to be able to isolate the pump. Isolation can be done by
installing valves in suction and discharge lines.
• Thesevalvesmusthaveacylindricalpassage
of the same diameter of the piping (full bore).
(Gate or ball valves are preferable).
• Whenoperatingthepump,thevalvesmustbeopened
completely. The output must never
be regulated by means of closing
valves in suction or discharge
pipes.
It must be regulated by changing
shaft speed or by re-routing the
media over a by-pass back to the
supply tank.
3.18.6.4 Strainer
Foreign particles can seriously damage the pump. Avoid the entry of these particles by installing a
strainer.
• Whenselectingthestrainerattentionshouldbegiventothesizeoftheopeningssothat
pressure losses are minimised. The cross-sectional area of the strainer must be three times that
of the suction pipe.
• Installthestrainerinsuchawaythatmaintenanceandcleaningarepossible.
• Makesurethatthepressuredropinthestraineriscalculatedwiththerightviscosity.Heatthe
strainer if necessary to reduce viscosity and pressure drop.
For the maximum allowable particle size see section 3.15.
3.18.7 Secondary piping
For dimensions of connections and plugs see chapter 6.0.
3.18.7.1 Drain lines
The pump is provided with drain plugs.
Discharge
By-pass
Piping
Suction