Valve Concepts 3000 SERIES Installation, Operation And Maintenance Manual

Also see for 3000 SERIES: Installation, operation and maintenance manual Installation, operation and maintenance manual

Contents

Valve Concepts 3000 SERIES Installation, Operation And Maintenance Manual Manual pdf 4 page image

4 IOM-3100Tank or system protection is the primary functionof the weight loaded Pressure and/or VacuumRelief Vent. As a safety device, it is very importantthat maintenance/inspection be done on a regularinterval. Maintenance should only be done by aqualified technician. Valve Concepts recommendsthat all service be performed at the factory or afactory authorized repair center. For information onrepair centers in your area, please contact factory.Maintenance procedures hereinafter are basedupon removal of the relief vent unit from the tankwhere installed.Owner should refer to Owner’s procedures for removal,handling and cleaning of nonreusable parts, i.e.gaskets, suitable solvents, etc.NOTE: Item Numbers that are specific to FRP bodymaterial are in parenthesis and underscored; i.e. (8).See Figure 11. Item Numbers that are generic to allbody materials are not underscored; i.e. (1). SeeFigures 3 thru 9 where applicable.To Dis-assemble: Remove the weatherhood wingnuts (12), (10 & 33) lift off weatherhood (13) andscreen (31).Remove vacuum cover cap screws (10), vacuumcover (8) and the TFE tape / rope seal (34).Inspect weatherhood (13), screen (31), and cover(8) for corrosion, damage or foreign material. Cleanwith a suitable solvent, replace as necessary.NOTE: During re-assembly, install new TFE tape /rope (34). For FRP material - nuts (10) for cover (8)should be tightened to 50 in. - lbs. (5.6 Nm).Remove pressure and vacuum pallet assemblies,including any loading weights (21 & 28) that maybe on the pallets (19,26). NOTE: As the palletsare removed from the vent, identify each assembly(including the stack of weights) by tagging as“pressure” side or “vacuum” side.Clean and inspect pallet assemblies. Inspect thediaphragms (18,25) and replace if necessary.To Replace Diaphragms - Std. Construction:See Figure 4. Secure pressure or vacuum stemassembly (23,30) in a soft-jawed vise with short,threaded end up. Remove washer and nut (14).For settings above 32oz/in2 See Figure 5. Removemachine screws (43) CCW.Lift up to remove diaphragm retainer (17,24),diaphragm (18,25) and pallet (19,26) and stiffenerplate (20,27). Clean parts with a suitable solvent,replace as necessary. NOTE: Before re-assembly,apply TFE paste to threads of the stem and aroundcenter hole on the pallets (19,26).Place stiffener plate (20,27) over threaded end ofstem. Set diaphragm (18,25) and diaphragm retainerplate (17,24) over end of stem. Install washer andnut (14) tight on stem.For settings above 32oz/in2 See Figure 5 forassembly. Install machine screws (43).Inspect and clean pressure / vacuum seat ring(s)(16). Check seat surface for any nicks, corrosion,pitting or foreign material. Seat surfaces must beclean and smooth for diaphragm and pallet to sealproperly. NOTE: FRP seat surfaces are integralinside the body.To Remove Seat Rings (except for FRP bodymaterial): Make a match mark between the seatring and the body. Rotate cap screws (15) CCWand remove. Remove pallet guides (22,29). (Useflats on the pressure guides or the slot on top of thevacuum guides and rotate CCW to remove.) Markthe location of each guide on the seat ring (16)flange for reference at re-assembly.Lift up to remove seat rings (16) and TFE tape /rope seal(s) (34.1). (There is no rope seal on FRPmaterial.) Inspect guides (22,29) and inside cavityof the body (1) for any corrosion or product build up.Clean all parts as necessary.SECTION VV. MAINTENANCEWARNINGWhen assembling a P/V vent, always put the pressure(long stem) and vacuum (short stem) pallet assembliesback in their original location and ensure that the stem isstraight and fits into the guide in the cover or weatherhood.If the pressure and vacuum pallet assemblies are mixedat re-assembly, the settings will be changed and the flowfor the vacuum side will be restricted.If the stem is cocked at an angle, pallet lift may be com-pletely blocked. An over-pressure can occur if any ofthese three conditions happens. This can cause a tankfailure, severe personal injury and material damage.