Free Discharge

Free-discharge safety valves are used to protect piping, vessels, and auxiliary equipment from overpressure where the relieved medium can be discharged directly to a safe atmospheric location. Typical service includes steam, water, air, and technical gases. Valve selection should be based on set pressure, required relieving capacity, fluid phase, operating temperature, seat material, and permissible discharge conditions.

This category includes Nuova safety valves in types B, C, D, F, FKS, and Z, as well as Valfonta ALPER atmospheric valves. Sizing must be correlated with nozzle orifice area, reduced flow coefficient, and the certified set pressure range. Indicatively, Nuova series cover orifice areas from 38.47 mm² for type Z7 up to 1256.00 mm² for type F40, with set pressure ranges that, depending on model and approval basis, extend to 30 bar.

During installation, attention should be given to inlet pressure loss, discharge direction, personnel protection from hot fluid or gas jet release, drainage of possible condensate, and accessibility for periodic testing. In steam and gas service, discharge outlet location requires particular care so that free atmospheric relief does not create thermal, acoustic, or mechanical hazards in the operating area.

Available versions include DIN executions in PN16, PN25, and PN40, with ISO 228, EN 10226, and NPT threads, as well as flanged or special end connections on selected types. Body and trim materials include brass, mixed brass–stainless steel construction, stainless steel, and ASTM A351 CF8M. Available seat materials include NBR, EPDM, Viton, Silicone, PTFE, Kalrez, and metal seat execution, selected according to temperature limits, chemical compatibility, and leakage tightness requirements.

Safety Valves Free Discharge - B12 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - B12 | Nuova

Safety Valves Free Discharge - B12 | Nuova
Nuova General Instruments
Nuova B12 Direct Discharge Safety Valve The Nuova B12 is a spring-loaded safety valve designed for applications where direct discharge to atmosphere is required and no outlet piping is permitted. The discharge orifice is 12 mm (area: 113.04 mm²). Suitable for gases, steam, and clean liquids without suspended solids. Technical Data Pressure Class (PN):...
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Safety Valves Free Discharge - B20 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - B20 | Nuova

Safety Valves Free Discharge - B20 | Nuova
Nuova General Instruments
Nuova B20 Safety Relief Valve – Atmospheric Discharge The Nuova B20 is a spring-loaded safety relief valve designed for installations where discharge is vented directly to atmosphere, without downstream piping. The discharge orifice is 20 mm (area 314 mm²), suitable for gases, steam, and clean liquids without suspended solids. Technical Data PN: 60 Set...
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Safety Valves Free Discharge - B38 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - B38 | Nuova

Safety Valves Free Discharge - B38 | Nuova
Nuova General Instruments
Nuova B38 Atmospheric Discharge Safety Valve The Nuova B38 is a spring-loaded safety valve designed for installations where direct atmospheric discharge is required, with no outlet piping. The discharge orifice is 38 mm (area 1133.54 mm²), suitable for gases, steam, and clean liquids without suspended solids. Technical Data PN: 40 Set Pressure (CE / UKCA...
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Safety Valves Free Discharge - C10 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - C10 | Nuova

Safety Valves Free Discharge - C10 | Nuova
Nuova General Instruments
Nuova C10 Direct Discharge Safety Valve The Nuova C10 is a spring-loaded safety valve designed for direct discharge (open outlet, no discharge piping). The discharge orifice is 10 mm (area: 78.50 mm²). Typical applications include small pressure vessels, air lines, test gases, steam, and technical fluids, provided local discharge is permissible. Technical...
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Safety Valves Free Discharge - D7 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - D7 | Nuova

Safety Valves Free Discharge - D7 | Nuova
Nuova General Instruments
Nuova D7 Spring-Loaded Safety Valve for Atmospheric Discharge The Nuova D7 is a spring-loaded safety valve designed for direct atmospheric discharge, without an outlet connection to piping. The discharge orifice is 7 mm (area 38.47 mm²), suitable for low flow rates of gases, steam, and clean liquids without suspended solids. Technical Data PN: 60 Set...
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Safety Valves Free Discharge - D10 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - D10 | Nuova

Safety Valves Free Discharge - D10 | Nuova
Nuova General Instruments
Nuova D10 Direct-Relief Safety Valve The Nuova D10 is a spring-loaded safety valve designed for direct atmospheric discharge. This model does not provide an outlet connection for discharge piping. The orifice diameter is 10 mm with a discharge area of 78.50 mm². Suitable for gases, steam, and liquids free from solids or particulates. Technical Data PN:...
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Safety Valves Free Discharge - D14 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - D14 | Nuova

Safety Valves Free Discharge - D14 | Nuova
Nuova General Instruments
Nuova D14 Free Discharge Safety Valve The Nuova D14 is a spring-loaded safety valve designed for direct atmospheric discharge, without an outlet connection for piping. The discharge orifice is 14 mm (area 153.86 mm²), suitable for protecting small vessels, air lines, steam systems, and technical fluids from overpressure. Technical Data Pressure Class...
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Safety Valves Free Discharge - F18 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - F18 | Nuova

Safety Valves Free Discharge - F18 | Nuova
Nuova General Instruments
Nuova F18 Safety Valve for Atmospheric Discharge The Nuova F18 is a spring-loaded safety valve designed for direct atmospheric discharge. It does not include an outlet connection for piping. The discharge orifice is 18 mm in diameter, with an effective area of 254.34 mm². Suitable for gases, steam, and clean liquids without suspended solids or...
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Safety Valves Free Discharge - F25 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - F25 | Nuova

Safety Valves Free Discharge - F25 | Nuova
Nuova General Instruments
Nuova F25 Direct Discharge Safety Valve The Nuova F25 is a spring-loaded safety valve designed for direct atmospheric discharge. It does not feature an outlet connection for piping; the discharge port is open to atmosphere. The orifice diameter is 25 mm (area: 490.63 mm²), suitable for gases, steam, and clean liquids without suspended solids. Technical...
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Safety Valves Free Discharge - F32 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - F32 | Nuova

Safety Valves Free Discharge - F32 | Nuova
Nuova General Instruments
Nuova F32 Atmospheric Safety Relief Valve The Nuova F32 is a spring-loaded safety relief valve designed for direct atmospheric discharge. The valve does not feature an outlet connection for piping; discharge occurs through a 32 mm orifice (803.84 mm² area). Suitable for gases, steam, and clean liquids without suspended solids. Technical Data Pressure...
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Safety Valves Free Discharge - F40 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - F40 | Nuova

Safety Valves Free Discharge - F40 | Nuova
Nuova General Instruments
Nuova F40 Atmospheric Discharge Safety Valve The Nuova F40 is a spring-loaded safety valve designed for direct atmospheric discharge. It does not feature an outlet connection for discharge piping. The orifice diameter is 40 mm with a discharge area of 1256 mm². Suitable for gases, steam, and clean liquids without suspended solids. Technical Data...
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Safety Valves Free Discharge - FKS25 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - FKS25 | Nuova

Safety Valves Free Discharge - FKS25 | Nuova
Nuova General Instruments
Nuova FKS25 Atmospheric Discharge Safety Valve The Nuova FKS25 is a spring-loaded safety valve designed for direct atmospheric discharge. The discharge orifice is 25 mm (area: 490.63 mm²). This valve is intended for low-pressure equipment protection where venting is not routed to a header or collection system. Technical Data PN: 10 Set Pressure Range:...
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Safety Valves Free Discharge - Z7 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - Z7 | Nuova

Safety Valves Free Discharge - Z7 | Nuova
Nuova General Instruments
Nuova Z7 Spring-Loaded Safety Valve with Free Discharge The Nuova Z7 is a spring-loaded safety valve designed for direct atmospheric discharge, without an outlet connection to piping. The discharge orifice is 7 mm (area 38.47 mm²), suitable for low flow rates of gases, steam, and clean liquids without particulates or solids. Technical Data Pressure Class...
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Safety Valves Free Discharge - Z10 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - Z10 | Nuova

Safety Valves Free Discharge - Z10 | Nuova
Nuova General Instruments
Nuova Z10 Safety Relief Valve – Atmospheric Discharge The Nuova Z10 is a spring-loaded safety relief valve designed for direct atmospheric discharge, with no outlet connection to piping. Discharge orifice diameter is 10 mm (area 78.50 mm²), suitable for low flow rates of gases, steam, and clean liquids without suspended solids. Technical Data PN: 16 Set...
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Safety Valves Free Discharge - Z14 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - Z14 | Nuova

Safety Valves Free Discharge - Z14 | Nuova
Nuova General Instruments
Nuova Z14 Direct Discharge Safety Valve The Nuova Z14 is a spring-loaded safety valve designed for direct atmospheric discharge, with no outlet connection to a discharge pipe. The discharge orifice is 14 mm (area 153.86 mm²), suitable for small-scale applications involving gases, steam, and clean liquids without solid particulates. Technical Data...
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Safety Valves Free Discharge - Z20 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - Z20 | Nuova

Safety Valves Free Discharge - Z20 | Nuova
Nuova General Instruments
Nuova Z20 Direct-Relief Safety Valve The Nuova Z20 is a spring-loaded safety valve designed for direct atmospheric discharge, with no outlet connection to piping. The discharge orifice is 20 mm (area 314 mm²), suitable for small-scale gas, steam, and liquid applications where solids are not present. Technical Data Pressure Class (PN): 16 Set Pressure...
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Safety Valves Free Discharge - Z25 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - Z25 | Nuova

Safety Valves Free Discharge - Z25 | Nuova
Nuova General Instruments
Nuova Z25 Safety Valve for Atmospheric Discharge The Nuova Z25 is a spring-loaded safety valve designed for direct atmospheric discharge, with no outlet connection to piping. The discharge orifice is 25 mm (area 490.63 mm²), suitable for gases, steam, and clean liquids without particulates or suspended solids. Technical Data PN: 16 Set Pressure Range:...
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Safety Valves Free Discharge - Z32 | Nuova | Philippopoulos s.a.

Safety Valves Free Discharge - Z32 | Nuova

Safety Valves Free Discharge - Z32 | Nuova
Nuova General Instruments
Nuova Z32 Direct Discharge Safety Valve The Nuova Z32 is a spring-loaded safety valve designed for direct atmospheric discharge. This model does not provide an outlet connection for discharge piping. The orifice diameter is 32 mm with a discharge area of 803.84 mm². Suitable for gases, steam, and clean liquids without suspended solids or particulates....
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Safety Valves series ALPER atmospheric valves | Valfonta | Philippopoulos s.a.

Safety Valves series ALPER atmospheric valves | Valfonta

Safety Valves series ALPER atmospheric valves | Valfonta
Valfonta
Valfonta ALPER Atmospheric Pressure/Vacuum Relief Valves Valfonta ALPER atmospheric valves are designed for the protection of storage tanks and closed vessels against overpressure and vacuum conditions. These valves feature a modulating opening characteristic, utilizing adjustable springs for pressure, vacuum, or combined pressure/vacuum settings. Outlet...
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