F44 gate valves, also known as 254 SMO valves or UNS S31254 valves, are valves made of high-molybdenum super austenitic stainless steel. The core advantages of F44 gate valves are: extreme resistance to chlorine corrosion + high strength, making them specifically designed for high-chlorine operating conditions.
① High resistance to pitting and crevice corrosion (PREN≈42–44, far exceeding 316L's 24 and 904L's 36), making them the preferred valve for high-chlorine environments such as seawater and brine;
② Excellent resistance to stress corrosion cracking (SCC), exhibiting significantly better SCC resistance than ordinary austenitic and duplex steels in chlorine-containing + high-temperature water environments;
③ Strong acid and alkali resistance, resistant to sulfuric acid, phosphoric acid, acetic acid, formic acid, and alkaline solutions, with a wide applicable pH range.
With a yield strength ≥300MPa and tensile strength ≥650MPa, lightweight valve designs are possible.
① When the temperature is below -50℃, the toughness decreases, so F44 gate valves are not suitable for extremely cold conditions without insulation;
② When the temperature is above 400℃, the strength decreases significantly, so F44 gate valves should avoid prolonged use at high temperatures.
4.1 The core application scenario for Freeman Valve's F44 gate valves is in the marine and seawater industry. Examples include: seawater desalination (concentrated brine pipelines, etc.), ships and offshore platforms (ballast water systems, fire-fighting pipelines, subsea pipelines, wellheads, etc.), and coastal power plants (seawater cooling systems, condensers, circulating water pipelines, etc.);
4.2 Freeman Valve's F44 gate valves have been widely used in the chemical and pharmaceutical industries. Examples include: chlor-alkali industry (brine refining, electrolytic cell accessories, chlorine treatment pipelines), pulp bleaching (chlorine dioxide, sodium hypochlorite media equipment, scrubbing towers), and fine chemicals (chlorine-containing intermediate reaction vessels, distillation towers). 4.3 Freeman Valve's F44 gate valves are widely used in the oil and gas and energy sectors. Examples include: wellhead equipment, throttle valves, and gathering pipelines for oil and gas extraction (high-chlorine, high-salinity formation water).
4.4 Freeman Valve's F44 gate valves are widely used in brine and brines (evaporators and crystallizers in Salt Lake chemical plants and salt production facilities), and high-temperature, high-chlorine water (closed-loop circulating water in thermal power plants, hot springs, and heat exchangers in geothermal equipment).
Design Standard of F44 Gate Valve (UNS S31254 Gate Valve):
Design Acc. to ASME B16.34 (ANSI Standard F44 Gate Valve (UNS S31254 Gate Valve));
Design Acc. to EN-12516-1/2 (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve)).
Test Standard of F44 Gate Valve (UNS S31254 Gate Valve):
Test Acc. to API 598 (ANSI Standard F44 Gate Valve (UNS S31254 Gate Valve));
Test Acc. to EN 12266-1/2 (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve)).
Surface Finishing of F44 Gate Valve (UNS S31254 Gate Valve):
All F44 Gate Valve (UNS S31254 Gate Valve) surface is finely machined to achieve the required roughness and conforms to standard MSS SP-110.
Size of F44 Gate Valve (UNS S31254 Gate Valve):
From DN1/4’’ to 48’’ (ANSI Standard F44 Gate Valve (UNS S31254 Gate Valve));
From DN8 to DN1200 (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve)).
Face to Face of F44 Gate Valve (UNS S31254 Gate Valve):
Face to Face Acc. to ASME B16.10 (ANSI Standard F44 Gate Valve (UNS S31254 Gate Valve));
Face to Face Acc. to EN 558-1 (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve)).
Pressure Rating of F44 Gate Valve (UNS S31254 Gate Valve):
ANSI Class 150 F44 Gate Valve (UNS S31254 Gate Valve) (ANSI Standard F44 Gate Valve (UNS S31254 Gate Valve));
ANSI Class 300 F44 Gate Valve (UNS S31254 Gate Valve) (ANSI Standard F44 Gate Valve (UNS S31254 Gate Valve));
ANSI Class 600 F44 Gate Valve (UNS S31254 Gate Valve) (ANSI Standard F44 Gate Valve (UNS S31254 Gate Valve));
ANSI Class 800 F44 Gate Valve (UNS S31254 Gate Valve) (ANSI Standard F44 Gate Valve (UNS S31254 Gate Valve));
ANSI Class 900 F44 Gate Valve (UNS S31254 Gate Valve) (ANSI Standard F44 Gate Valve (UNS S31254 Gate Valve));
ANSI Class 1500 F44 Gate Valve (UNS S31254 Gate Valve) (ANSI Standard F44 Gate Valve (UNS S31254 Gate Valve));
ANSI Class 2500 F44 Gate Valve (UNS S31254 Gate Valve) (ANSI Standard F44 Gate Valve (UNS S31254 Gate Valve));
EN 1092 PN 16 F44 Gate Valve (UNS S31254 Gate Valve) (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve));
EN 1092 PN 25 F44 Gate Valve (UNS S31254 Gate Valve) (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve));
EN 1092 PN 40 F44 Gate Valve (UNS S31254 Gate Valve) (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve));
EN 1092 PN 63 F44 Gate Valve (UNS S31254 Gate Valve) (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve));
EN 1092 PN 100 F44 Gate Valve (UNS S31254 Gate Valve) (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve));
EN 1092 PN 160 F44 Gate Valve (UNS S31254 Gate Valve) (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve));
EN 1092 PN 250 F44 Gate Valve (UNS S31254 Gate Valve) (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve));
EN 1092 PN 320 F44 Gate Valve (UNS S31254 Gate Valve) (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve));
EN 1092 PN 400 F44 Gate Valve (UNS S31254 Gate Valve) (EN Standard F44 Gate Valve (UNS S31254 Gate Valve), DIN Standard F44 Gate Valve (UNS S31254 Gate Valve)).
Working Temperature of F44 Gate Valve (UNS S31254 Gate Valve):
Please refer to the "Temperature and Pressure Curve of F44 Gate Valve (UNS S31254 Gate Valve)" for temperature and pressure changes.
Ends Connection of F44 Gate Valve (UNS S31254 Gate Valve):
ANSI Flange Ends F44 Gate Valve (UNS S31254 Gate Valve);
ANSI Integral Flange Ends F44 Gate Valve (UNS S31254 Gate Valve);
ANSI Welded Flange Ends F44 Gate Valve (UNS S31254 Gate Valve);
Butt Weld (ASME B16.25) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Butt Weld x ANSI Flange Ends F44 Gate Valve (UNS S31254 Gate Valve);
EN 1092 Flange Ends F44 Gate Valve (UNS S31254 Gate Valve);
EN 1092 Integral Flange Ends F44 Gate Valve (UNS S31254 Gate Valve);
EN 1092 Welded Flange Ends F44 Gate Valve (UNS S31254 Gate Valve);
Butt Weld (EN 12627) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Butt Weld (ISO 1127) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Butt Weld x EN 1092 Flange Ends F44 Gate Valve (UNS S31254 Gate Valve);
Male NPT (ASME B1.20.1) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Male BSPP (ISO 228-1) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Male BSPT (ISO 7-1) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Male NPT x Female NPT Ends F44 Gate Valve (UNS S31254 Gate Valve);
Male BSPP x Female BSPP Ends F44 Gate Valve (UNS S31254 Gate Valve);
Male BSPT x Female BSPT Ends F44 Gate Valve (UNS S31254 Gate Valve);
Male NPT x Long Butt Weld (+100 mm) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Male BSPP x Long Butt Weld (+100 mm) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Male BSPT x Long Butt Weld (+100 mm) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female NPT (ASME B1.20.1) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female BSPP (ISO 228-1) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female BSPT (ISO 7-1) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Socket Weld (ASME B16.11) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Socket Weld (EN 12760) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female NPT x Socket Weld Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female BSPP x Socket Weld Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female BSPT x Socket Weld Ends F44 Gate Valve (UNS S31254 Gate Valve);
Butt Weld (ASME B16.25) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Butt Weld (EN 12627) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female NPT x Butt Weld Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female BSPP x Butt Weld Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female BSPT x Butt Weld Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female NPT x Long Butt Weld (+100 mm) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female BSPP x Long Butt Weld (+100 mm) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Female BSPT x Long Butt Weld (+100 mm) Ends F44 Gate Valve (UNS S31254 Gate Valve);
Long Butt Weld (+100 mm Weld Stub) Ends F44 Gate Valve (UNS S31254 Gate Valve).
CE Marking of F44 Gate Valve (UNS S31254 Gate Valve):
CE Marking is Available to F44 Gate Valve (UNS S31254 Gate Valve) with a Diameter of DN32 or Larger.
Chemical Composition of F44 Gate Valve (UNS S31254 Gate Valve):
For the Chemical Composition of F44 Gate Valve (UNS S31254 Gate Valve), please refer to EN 10204 Type 3.1 certificate.
Mechanical Properties of F44 Gate Valve (UNS S31254 Gate Valve):
For the Mechanical Properties of F44 Gate Valve (UNS S31254 Gate Valve), please refer to EN 10204 Type 3.1 certificate.
Certificate of F44 Gate Valve (UNS S31254 Gate Valve):
All F44 Gate Valve (UNS S31254 Gate Valve) will be delivered with EN 10204 Type 3.1 Certificate.
Approvals of F44 Gate Valve (UNS S31254 Gate Valve):
MSS SP-110 Certified of F44 Gate Valve (UNS S31254 Gate Valve);
NACE MR 0175 Certified of F44 Gate Valve (UNS S31254 Gate Valve)
API 607 Fire Safe Certified of F44 Gate Valve (UNS S31254 Gate Valve);
ISO 9001 Certified of F44 Gate Valve (UNS S31254 Gate Valve);
PED Certified of F44 Gate Valve (UNS S31254 Gate Valve).
Available Upon Request of F44 Gate Valve (UNS S31254 Gate Valve):
NACE MR0175 is available upon request of F44 Gate Valve (UNS S31254 Gate Valve);
ATEX is available upon request of F44 Gate Valve (UNS S31254 Gate Valve);
TA-LUFT is available upon request of F44 Gate Valve (UNS S31254 Gate Valve);
SIL is available upon request of F44 Gate Valve (UNS S31254 Gate Valve);
Degreasing is available upon request of F44 Gate Valve (UNS S31254 Gate Valve);
Fire Safe is available upon request of F44 Gate Valve (UNS S31254 Gate Valve);
Stem Extension is available upon request of F44 Gate Valve (UNS S31254 Gate Valve);
Double Block and Bleed is available upon request of F44 Gate Valve (UNS S31254 Gate Valve).
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