Key Features and What They Mean in Service<\/h2>\n\n- Relief valve removal and replacement without shutting down or evacuating the container.<\/strong>\u00a0This is the defining benefit of the product. Periodic valve replacement becomes a maintenance task rather than a production event.<\/li>\n
- Unique seat ring assemblies with a smooth tubular section.<\/strong>\u00a0The geometry reduces turbulence through the manifold, which is what protects flow capacity against friction loss \u2014 the mechanism behind the assembly-level rating described above.<\/li>\n
- An operating lever that locks only in the mid-position or in a position to seal either relief valve.<\/strong>\u00a0This is a safety-critical design detail, not a convenience. If the clapper disc is left in an intermediate position, flow through one of the relief valves can be restricted, causing that valve to chatter \u2014 and chatter destroys the resilient seat disc. The lever’s limited travel positions exist to make the intermediate state impossible to leave the manifold in.<\/li>\n
- A rubber plug with chain to protect the manifold outlet threads.<\/strong>\u00a0When a relief valve is removed, the exposed outlet thread is vulnerable to damage and contamination. The captive plug protects the thread so the replacement valve seats correctly.<\/li>\n
- “Pop-action” design.<\/strong>\u00a0The relief valves open decisively at moderately excessive pressures, giving maximum protection with only minimal product loss.<\/li>\n
- Resilient relief valve seat disc for a “bubble-tight” seal.<\/strong>\u00a0After a discharge event the valve re-seals tightly rather than weeping product.<\/li>\n
- ASME rated for LP-Gas and anhydrous ammonia.<\/strong>\u00a0Both service media are covered by the relief valve rating.<\/li>\n<\/ul>\n
\n\n\nProduct type<\/td>\n DuoPort pressure relief valve manifold for small storage containers<\/td>\n<\/tr>\n \nSeries<\/td>\n 8542<\/td>\n<\/tr>\n \nContainer connection<\/td>\n 2 in. M.NPT (threaded coupling)<\/td>\n<\/tr>\n \nRelief valves per manifold<\/td>\n 2<\/td>\n<\/tr>\n \nRelief valve inlet connection<\/td>\n 1-1\/4 in. M.NPT<\/td>\n<\/tr>\n \nPipeway adaptor outlet<\/td>\n 2 in. F.NPT<\/td>\n<\/tr>\n \nOverall width<\/td>\n 6 1\/4 in.<\/td>\n<\/tr>\n \nOverall height (approx.)<\/td>\n 11 1\/16 in.<\/td>\n<\/tr>\n \nManifold body material<\/td>\n Ductile iron<\/td>\n<\/tr>\n \nClapper disc \/ bleeder valve<\/td>\n Stainless steel<\/td>\n<\/tr>\n \nManifold seat disc<\/td>\n Teflon<\/td>\n<\/tr>\n \nPacking<\/td>\n Polyethylene<\/td>\n<\/tr>\n \nRelief valve body<\/td>\n Forged aluminum (coated inlet threads)<\/td>\n<\/tr>\n \nRelief valve spring<\/td>\n Coated steel<\/td>\n<\/tr>\n \nRelief valve seat disc<\/td>\n Resilient synthetic rubber<\/td>\n<\/tr>\n \nCertification<\/td>\n UL Listed; relief valves ASME rated for LP-Gas and anhydrous ammonia<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n <\/p>\n
How to Select the Right DuoPort Manifold<\/h2>\n\n- Identify the medium.<\/strong>\u00a0LP-Gas \u2192 8542G. Anhydrous ammonia \u2192 AA8542UA250 or AA8542UA265.<\/li>\n
- Confirm the required start-to-discharge setting.<\/strong> 250 PSIG for the 8542G; 265 PSIG for the AA8542UA265 and AA8542UA250.<\/li>\n
- Confirm the container coupling.<\/strong>\u00a02 in. NPT on all three part numbers.<\/li>\n
- Establish the required relieving capacity and the rating basis.<\/strong>\u00a0Take the figure required by your code \u2014 UL or ASME \u2014 and use the matching column on the correct row.<\/li>\n
- Apply the one-valve basis and the accessory derating.<\/strong>\u00a0The published rating already assumes a single relief valve flowing; if a pipeway adaptor is fitted, the effective flow is lower again.<\/li>\n
- Check the physical envelope.<\/strong>\u00a06 1\/4 in. wide, approximately 11 1\/16 in. tall, with space to remove a relief valve for service.<\/li>\n
- Order the matching replacement relief valve and adaptor.<\/strong>\u00a03135MG with adaptor 3135-10 for the 8542G; AA3135MUA250 or AA3135MUA265 with adaptor AA3135-10 for the ammonia versions.<\/li>\n<\/ol>\n
Frequently Asked Questions (FAQ)<\/h2>\n
What is a DuoPort relief valve manifold?<\/strong><\/p>\nIt is an assembly that mounts two pressure relief valves on a single manifold body, using one container coupling. Its purpose is to let you remove, service, or replace either relief valve without shutting down and evacuating the container.<\/p>\n
How can a relief valve be removed without evacuating the container?<\/strong><\/p>\nThe operating lever selectively closes off the entrance port to the relief valve being removed, while the remaining valve continues to protect the container and its contents.<\/p>\n
What connection sizes does the 8542 Series use?<\/strong><\/p>\nA 2 in. M.NPT container connection, a 1-1\/4 in. M.NPT inlet on each relief valve, and a 2 in. F.NPT outlet on the pipeway adaptor.<\/p>\n
What set pressures are available?<\/strong><\/p>\n250 PSIG on the 8542G (LP-Gas) , and 265 PSIG on the AA8542UA265 (anhydrous ammonia) and the AA8542UA250 (anhydrous ammonia).<\/p>\n
What is the flow capacity of each part number?<\/strong><\/p>\nAt 120% of set pressure: the 8542G is rated 5,250 SCFM air (UL) with no ASME rating published; the AA8542UA250 is rated 6,430 SCFM (UL) and 6,341 SCFM (ASME); the AA8542UA265 is rated 6,615 SCFM (UL) and 6,703 SCFM (ASME).<\/p>\n
Why is the flow rating based on one relief valve when the manifold holds two?<\/strong><\/p>\n\u00a0Because the critical case is the one where a valve has been removed for service and only the remaining valve is protecting the container. The rating also accounts for friction loss through the manifold, so it is an assembly rating rather than a bare valve rating.<\/p>\n
Can the manifold be used with anhydrous ammonia?<\/strong><\/p>\nYes. The AA8542UA250 and AA8542UA265 are the ammonia part numbers, and the relief valves are ASME rated for use with LP-Gas and anhydrous ammonia.<\/p>\n
What does “NA” mean in the ASME column for the 8542G?<\/strong><\/p>\nNo ASME rating is published for the LP-Gas part number in that row; it carries a UL rating only. If your application requires an ASME-rated capacity on LP-Gas service, confirm the requirement with the manufacturer before specifying.<\/p>\n
Where should the operating lever be positioned?<\/strong><\/p>\nOnly in the mid-position or in a position that seals one relief valve. Leaving the clapper disc in an intermediate position can restrict flow through one relief valve, causing it to chatter and destroy the resilient seat disc.<\/p>\n
What materials are used in the assembly?<\/strong><\/p>\nThe manifold has a ductile iron body with a stainless steel clapper disc and bleeder valve, a Teflon seat disc, and polyethylene packing. Each relief valve has a forged aluminium body with a special coating on the inlet threads to minimise electrolytic action, an aluminium spring guide, a coated steel spring, and a resilient synthetic rubber seat disc.<\/p>\n","protected":false},"excerpt":{"rendered":"
Brand: REGO<\/span><\/div>\nModel: 8542G\u00a0[product_badge]<\/span><\/div>\nInterface size: 2 “NPT<\/span><\/div>\nConnection method: threaded connection<\/span><\/div>\n
| Product type<\/td>\n | DuoPort pressure relief valve manifold for small storage containers<\/td>\n<\/tr>\n |
| Series<\/td>\n | 8542<\/td>\n<\/tr>\n |
| Container connection<\/td>\n | 2 in. M.NPT (threaded coupling)<\/td>\n<\/tr>\n |
| Relief valves per manifold<\/td>\n | 2<\/td>\n<\/tr>\n |
| Relief valve inlet connection<\/td>\n | 1-1\/4 in. M.NPT<\/td>\n<\/tr>\n |
| Pipeway adaptor outlet<\/td>\n | 2 in. F.NPT<\/td>\n<\/tr>\n |
| Overall width<\/td>\n | 6 1\/4 in.<\/td>\n<\/tr>\n |
| Overall height (approx.)<\/td>\n | 11 1\/16 in.<\/td>\n<\/tr>\n |
| Manifold body material<\/td>\n | Ductile iron<\/td>\n<\/tr>\n |
| Clapper disc \/ bleeder valve<\/td>\n | Stainless steel<\/td>\n<\/tr>\n |
| Manifold seat disc<\/td>\n | Teflon<\/td>\n<\/tr>\n |
| Packing<\/td>\n | Polyethylene<\/td>\n<\/tr>\n |
| Relief valve body<\/td>\n | Forged aluminum (coated inlet threads)<\/td>\n<\/tr>\n |
| Relief valve spring<\/td>\n | Coated steel<\/td>\n<\/tr>\n |
| Relief valve seat disc<\/td>\n | Resilient synthetic rubber<\/td>\n<\/tr>\n |
| Certification<\/td>\n | UL Listed; relief valves ASME rated for LP-Gas and anhydrous ammonia<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n <\/p>\n How to Select the Right DuoPort Manifold<\/h2>\nFrequently Asked Questions (FAQ)<\/h2>\nWhat is a DuoPort relief valve manifold?<\/strong><\/p>\n It is an assembly that mounts two pressure relief valves on a single manifold body, using one container coupling. Its purpose is to let you remove, service, or replace either relief valve without shutting down and evacuating the container.<\/p>\n How can a relief valve be removed without evacuating the container?<\/strong><\/p>\n The operating lever selectively closes off the entrance port to the relief valve being removed, while the remaining valve continues to protect the container and its contents.<\/p>\n What connection sizes does the 8542 Series use?<\/strong><\/p>\n A 2 in. M.NPT container connection, a 1-1\/4 in. M.NPT inlet on each relief valve, and a 2 in. F.NPT outlet on the pipeway adaptor.<\/p>\n What set pressures are available?<\/strong><\/p>\n 250 PSIG on the 8542G (LP-Gas) , and 265 PSIG on the AA8542UA265 (anhydrous ammonia) and the AA8542UA250 (anhydrous ammonia).<\/p>\n What is the flow capacity of each part number?<\/strong><\/p>\n At 120% of set pressure: the 8542G is rated 5,250 SCFM air (UL) with no ASME rating published; the AA8542UA250 is rated 6,430 SCFM (UL) and 6,341 SCFM (ASME); the AA8542UA265 is rated 6,615 SCFM (UL) and 6,703 SCFM (ASME).<\/p>\n Why is the flow rating based on one relief valve when the manifold holds two?<\/strong><\/p>\n \u00a0Because the critical case is the one where a valve has been removed for service and only the remaining valve is protecting the container. The rating also accounts for friction loss through the manifold, so it is an assembly rating rather than a bare valve rating.<\/p>\n Can the manifold be used with anhydrous ammonia?<\/strong><\/p>\n Yes. The AA8542UA250 and AA8542UA265 are the ammonia part numbers, and the relief valves are ASME rated for use with LP-Gas and anhydrous ammonia.<\/p>\n What does “NA” mean in the ASME column for the 8542G?<\/strong><\/p>\n No ASME rating is published for the LP-Gas part number in that row; it carries a UL rating only. If your application requires an ASME-rated capacity on LP-Gas service, confirm the requirement with the manufacturer before specifying.<\/p>\n Where should the operating lever be positioned?<\/strong><\/p>\n Only in the mid-position or in a position that seals one relief valve. Leaving the clapper disc in an intermediate position can restrict flow through one relief valve, causing it to chatter and destroy the resilient seat disc.<\/p>\n What materials are used in the assembly?<\/strong><\/p>\n The manifold has a ductile iron body with a stainless steel clapper disc and bleeder valve, a Teflon seat disc, and polyethylene packing. Each relief valve has a forged aluminium body with a special coating on the inlet threads to minimise electrolytic action, an aluminium spring guide, a coated steel spring, and a resilient synthetic rubber seat disc.<\/p>\n","protected":false},"excerpt":{"rendered":" |
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