Flowserve ISC2 Série Instructions De Montage page 16

causes the machine to run dry at the seal gap for an indefinite
period, and the seal faces can become damaged.
7.3 For running a dual pressurized seal (double seal), supply a
clean, compatible barrier fluid at a pressure at least 25 psi
(1.7 bar) above the seal chamber pressure. See Figure 6. The
pressure of the barrier fluid must not exceed the recommended
maximum pressure.
Monitoring the liquid circulation is a recommended measure for
ensuring that the mechanical seal runs properly.
Dual pressurized (Plan 53A) ISC2 with Supply Tank
Figure 6
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