Installation & Maintenance - Protectoseal

Installation & Maintenance GuidePage 17PROTECTOSEAL SERIES NO. 20TANK BLANKETING VALVEPressure Gauges■ FUNCTIONOptional pressure gauges may be included which enable system pressure monitoring. Thesupply line pressure gauge will show the blanketing gas supply pressure at the inlet to andinside of the blanketing valve. The sense line pressure gauge will show the tank pressurebeing sensed by the blanketing valve through the sense line.■ MAINTENANCEWhen the blanketing valve has been completely depressurized, gauges may be removed forcalibration checks. Replacement gauges can be ordered if necessary. The sense line gaugesupplied by Protectoseal has a working pressure of up to 15 psig and so should not bedamaged by fluctuations in tank pressure. Damage to the supply pressure gauge may indicatethat the blanketing gas supply system was overpressurized at some point. Excessivesupply pressure can cause blanketing valve failure and should be immediately investigated.Fig. 12Pressure GaugesIntegral PurgeAccessories■ FUNCTIONThe integral purge is used to create a small flow of blanketing gas at the blanketing valveoutlet and/or the sense line connection in order to keep vapors from the material stored inthe tank from corroding the blanketing valve. Due to the blanketing valve’s stainless steel316 construction, the availability of chemically resistant soft goods, and the high concentrationof blanketing gas present in the blanketing valve, the integral purge should not be necessaryexcept in very severe service conditions. Both the blanketing valve