Series 740 Safety Relief Valves
Heavy-duty industrial workhorse for standard applications
Specifications
- Body Material: Brass/Bronze
- Trim Material: Brass nozzle, SS ring/disc/springs
- Max Pressure (Air/Liquid): 350 psig
- Max Pressure (Steam): 250 psig
- Temperature Range: -320°F to 406°F
- Connections: NPT, BSPT, BSPP, Tri-Clamp
- Certifications: ASME VIII, CE, CRN
Manufactured by Aquatrol • Authorized Distributor • American-Made
Series 741 Safety Relief Valves
Stainless trim for corrosion resistance and higher pressure
Specifications
- Body Material: Brass/Bronze
- Trim Material: 316 SS nozzle/ring/disc/springs
- Max Pressure (Air/Liquid): 1500 psig
- Max Pressure (Steam): 300 psig
- Temperature Range: -320°F to 425°F
- Connections: Threaded, Tri-Clamp, Flanges (150-900#)
- Certifications: ASME VIII, CE, CRN
Manufactured by Aquatrol • Authorized Distributor • American-Made
Series 742 Safety Relief Valves
High temperature capability with carbon steel body
Specifications
- Body Material: Carbon Steel
- Trim Material: 316 SS nozzle/ring/disc/internals/springs
- Max Pressure (Air/Liquid): 1500 psig
- Max Pressure (Steam): 300 psig
- Temperature Range: -20°F to 800°F
- Connections: NPT, BSPT, Tri-Clamp, Flanges
- Certifications: ASME VIII, CE, CRN
Manufactured by Aquatrol • Authorized Distributor • American-Made
Series 743 Safety Relief Valves
Full stainless construction for demanding environments
Specifications
- Body Material: 316 Stainless Steel
- Trim Material: 316 SS throughout
- Max Pressure (Air/Liquid): 1500 psig
- Max Pressure (Steam): 300 psig
- Temperature Range: -320°F to 800°F
- Connections: NPT, BSPT, Tri-Clamp, Flanges
- Certifications: ASME VIII, CE, CRN
Manufactured by Aquatrol • Authorized Distributor • American-Made
Overview
Replacing a safety or relief valve? These fit most industrial applications: compressors, pressure vessels, tanks, pumps, steam systems, and hydraulic circuits. All media types – air/gas, steam, liquid.
Choose from brass construction for standard service, or upgrade to stainless steel or carbon steel for corrosive environments, high temperatures (to 800°F), or higher pressures (to 1500 psig).
Certified ASME Section VIII, National Board, CE, CRN.
Commonly Specified Series 740 Configurations
Select one to review and confirm suitability for your application.
Lead time varies by configuration. Not sure which to choose? Use the configurator below.
Commonly Specified Series 742 Configurations
Select one to review and confirm suitability for your application.
Lead time varies by configuration. Not sure which to choose? Use the configurator below.
Configure & Price Your Valve
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Series 741 FAQs
Why choose 741 over 740?
Choose 741 when you need higher pressure ratings (up to 1500 psig vs 350), better corrosion resistance from the stainless trim, or flanged connections.
Series 742 FAQs
When should I use carbon steel vs stainless body?
Carbon steel (742) is preferred for high-temperature applications where cost is a factor. Choose all-stainless 743 for corrosive environments or when material consistency is required.
Series 743 FAQs
Is Series 743 suitable for oxygen service?
Yes, with the O2 cleaning option, Series 743 is suitable for oxygen service. The all-stainless construction combined with proper cleaning meets oxygen service requirements.
Frequently Asked Questions
What is the lead time for 740 Series valves?
Standard configurations typically ship within 14 business days. Valves are made to order.
Can I get a valve for cryogenic service?
Yes, with PTFE seating option, 740 Series valves can operate down to -320°F (-196°C) for cryogenic applications.
What's the difference between the series numbers?
The series number indicates body and trim materials: 740 is brass body with brass trim, 741 is brass body with 316 SS trim, 742 is carbon steel body with SS trim, and 743 is all 316 stainless steel construction.
Are flanged connections available?
Yes, lap-joint flanges are available for Series 741, 742, and 743 in classes 150 through 900. Series 740 is threaded only.