Kalpataru Piping Solution is a leading super duplex steel valve manufacturer in Mumbai, India. We supply a comprehensive range of super duplex valves — including ball valves, gate valves, globe valves, check valves, needle valves, manifold valves, and butterfly valves — manufactured from premium UNS S32750 (Duplex 2507) and UNS S32760 (Zeron 100) material. Our super duplex valves are supplied to offshore oil & gas, desalination, chemical processing, marine, and power generation industries across 40+ countries.
- What Makes Super Duplex Steel Valves the Engineer's First Choice?
- Super Duplex Steel Valve Material Grades
- Technical Specifications Super Duplex Steel Valves
- Types of Super Duplex Steel Valves
- Super Duplex Steel Valve Sizes and Dimensions
- Chemical Composition — Super Duplex Steel Grades
- Mechanical Properties — Super Duplex Steel Valve Materials
- Industry Applications of Super Duplex Steel Valves
- Quality Standards and Certifications
- Why Choose Kalpataru Piping Solution as Your Super Duplex Steel Valve Manufacturer
- Frequently Asked Questions — Super Duplex Steel Valves
What Makes Super Duplex Steel Valves the Engineer’s First Choice?
When corrosion dictates design, the material choice for valves is not a secondary consideration it is the project-critical decision. Engineers working on offshore platforms, seawater desalination units, or chlorinated chemical plants quickly encounter the performance ceiling of conventional stainless steels. Grade 316L fails in seawater chloride concentrations above 200 ppm at elevated temperatures. Standard duplex 2205 performs better, yet its PREN of 30–38 leaves it vulnerable in stagnant seawater, creviced geometries, and sour service with simultaneous high chloride loads.
Super duplex steel valves break through this ceiling. The defining characteristic is their chemical architecture: a precisely balanced two-phase ferritic-austenitic microstructure with approximately 25% chromium, 7% nickel, and 4% molybdenum, augmented by nitrogen (0.24–0.32%) and, in the case of Zeron 100 (UNS S32760), additions of tungsten and copper. This chemistry yields a Pitting Resistance Equivalent Number (PREN) consistently above 40, the internationally recognized threshold for super duplex classification.
The PREN formula %Cr + 3.3×%Mo + 16×%N quantifies a material’s resistance to chloride-induced pitting. A PREN above 40 indicates immunity to pitting in seawater at ambient temperatures and high resistance even at elevated temperatures, which is why super duplex is the mandatory specification for subsea Christmas trees, SWRO high-pressure brine systems, and offshore topside manifolds.
Beyond corrosion resistance, super duplex valves offer a tensile strength of 795–860 MPa nearly double that of 316L stainless steel (515 MPa minimum). This allows engineers to design thinner-walled, lighter valve bodies while maintaining full pressure containment, reducing weight on offshore topsides and lowering fabrication costs on high-alloy piping systems.
Kalpataru Piping Solution manufactures super duplex steel valves from forged billets of ASTM A182 F53 (UNS S32750) and ASTM A182 F55 (UNS S32760). Every heat is solution-annealed between 1,050°C and 1,100°C and water-quenched to achieve the target ferrite content of 40–55%, balancing strength, toughness, and corrosion resistance in a single thermal cycle.
Super Duplex Steel Valve Material Grades
Technical Specifications Super Duplex Steel Valves
|
Parameter |
Specification |
|
Material Grades |
UNS S32750 (ASTM A182 F53 / Duplex 2507), UNS S32760 (ASTM A182 F55 / Zeron 100) |
|
Valve Types |
Ball, Gate, Globe, Check, Needle, Manifold, Butterfly, Plug |
|
Size Range |
¼” to 24″ (DN 8 – DN 600); larger on request |
|
Pressure-Temperature Ratings |
ASME B16.34 Class 150 to Class 2500 |
|
End Connections |
Flanged (ASME B16.5), Butt Weld (ASME B16.25), Socket Weld, NPT/BSP Threaded, Compression (Instrumentation) |
|
Face-to-Face Dimensions |
ASME B16.10 |
|
Body / Bonnet |
ASTM A182 F53 / F55 forged; ASTM A351 CE8MN / CK3MCuN cast |
|
Trim Material |
Super duplex stem, ball, and seats (same or higher alloy) |
|
Seat Material |
PTFE, RPTFE, Metal-seated (super duplex or Inconel 625 hard-faced) |
|
Stem Seal |
PTFE chevron packing, Grafoil for high-temperature service |
|
Body Bolting |
ASTM A193 B8M (SS 316) studs with A194 8M nuts |
|
Temperature Range |
−50°C to +315°C (−58°F to +600°F) |
|
Operating Pressure |
Up to 420 bar (6,090 psi) depending on class and size |
|
PREN |
≥ 40 (confirmed on MTC per ASTM G48) |
|
Ferrite Content |
40–55% (measured by magnetic induction per ASTM E562 / Fischer Feritscope) |
|
Heat Treatment |
Solution annealed 1,050–1,100°C + rapid water quench |
|
Design Life |
25+ years in typical offshore / desalination service |
|
Actuation |
Manual (handwheel / lever / gear operator), pneumatic, electric, hydraulic |
|
Fire-Safe Design |
API 607 / API 6FA on request |
|
Anti-Static Device |
Per API 608 / ISO 7121 |
|
Fugitive Emission |
ISO 15848-1 Class B / C on request |
|
Hardness (NACE) |
≤ HRC 36 on all pressure-retaining parts (per NACE MR0175/ISO 15156) |
Types of Super Duplex Steel Valves
Kalpataru Piping Solution manufactures the following super duplex valve types, each designed for specific process isolation and control functions:
1. Super Duplex Ball Valve
The super duplex ball valve is the most widely specified type for on/off isolation service. A spherical closure member with a full or reduced bore rotates 90° to open or close flow. Super duplex ball valves offer bubble-tight sealing, low operating torque, and high flow capacity (Cv). Available as floating ball (Class 150–600) and trunnion-mounted (Class 150–2500). Specifications: API 6D, API 608, ASME B16.34.
Key applications: Pipeline isolation, subsea manifolds, SWRO feed headers, chemical reactor inlet/outlet.
Super Duplex Steel Instrumentation Ball Valve
2. Super Duplex Gate Valve
Gate valves provide bi-directional isolation with minimum pressure drop when fully open. The wedge or slab gate slides perpendicular to flow, making them ideal for full-bore, infrequent operation. Available as rising stem (RS) or non-rising stem (NRS). Specifications: API 600, ASME B16.34, MSS SP-70.
Key applications: Mainline block valves, pump suction and discharge, produced water injection.
3. Super Duplex Globe Valve
Globe valves are preferred for throttling and flow regulation. The disc moves axially against a seat ring, enabling fine flow control. Super duplex globe valves are specified for high-velocity, erosive, or corrosive streams where precise modulation is required. Specifications: ASME B16.34, MSS SP-80.
Key applications: Bypass lines, flow control loops, choke service upstream of metering systems.
4. Super Duplex Check Valve
Check valves allow unidirectional flow and prevent reverse flow automatically. Available as swing check, piston (lift) check, and dual-plate wafer check. Super duplex check valves protect pumps, compressors, and sensitive instruments from backflow damage.
Key applications: Pump discharge, compressor outlet, injection systems, downhole tubing strings.
5. Super Duplex Needle Valve
Needle valves provide fine metering and positive shut-off for instrumentation and small-bore process lines. The tapered needle-shaped plug seats into a conical seat for precise flow control. Available in 2-way, 3-way, and block-and-bleed configurations.
Key applications: Pressure gauge root valves, sample points, chemical injection, hydraulic control panels.
Super Duplex Steel Needle Valve S32750/S32760
6. Super Duplex Manifold Valve
Manifold valves (2-valve, 3-valve, and 5-valve configurations) are used in differential pressure transmitter hookups, pressure gauge isolation, and instrument impulse line isolation. They eliminate multiple pipe fittings and reduce leak paths.
Key applications: DP transmitter connections, level gauges, pressure transmitters in offshore instrument panels.
Super Duplex Steel Manifold Valve
7. Super Duplex Butterfly Valve
Butterfly valves offer a compact, lightweight design for large-bore isolation and throttling. The disc rotates 90° within the pipeline. High-performance (double-offset) and triple-offset designs are available for super duplex service. Specifications: API 609, ASME B16.34.
Key applications: Seawater cooling headers, ballast water treatment, FGD bypass lines, large-diameter isolation.
8. Super Duplex Plug Valve
Plug valves use a cylindrical or conical tapered plug for on/off or diverting service. Lubricated and non-lubricated variants are available. Super duplex plug valves are preferred for slurry, high-solid-content, and abrasive service where ball valves may suffer seat erosion.
Key applications: Produced water slurry lines, gypsum slurry in FGD systems, abrasive chemical streams.
Super Duplex Steel Valve Sizes and Dimensions
Kalpataru supplies super duplex steel valves across a wide size range to cover instrumentation, process, and pipeline applications. Dimensions conform to ASME B16.34 (pressure class) and ASME B16.10 (face-to-face), with flange drilling to ASME B16.5 and butt-weld ends to ASME B16.25.
Size Range by Valve Type
|
Valve Type |
Size Range |
Pressure Class |
End Connection |
|
Ball Valve (Floating) |
¼” – 4″ (DN 8–100) |
Class 150–600 |
RF Flanged, SW, NPT, BW |
|
Ball Valve (Trunnion) |
2″ – 24″ (DN 50–600) |
Class 150–2500 |
RF/RTJ Flanged, BW |
|
Gate Valve |
½” – 24″ (DN 15–600) |
Class 150–2500 |
RF/RTJ Flanged, BW |
|
Globe Valve |
½” – 12″ (DN 15–300) |
Class 150–2500 |
RF Flanged, SW, BW |
|
Check Valve (Swing) |
½” – 24″ (DN 15–600) |
Class 150–2500 |
RF Flanged, BW |
|
Check Valve (Dual Plate) |
2″ – 48″ (DN 50–1200) |
Class 150–600 |
Wafer, Lugged |
|
Needle Valve |
¼” – 2″ (DN 6–50) |
Up to 6,000 psi |
NPT, SW, Compression |
|
Manifold Valve (2V) |
¼” – ¾” (DN 8–20) |
Up to 6,000 psi |
NPT, SW, Direct Mount |
|
Manifold Valve (3V/5V) |
¼” – ¾” (DN 8–20) |
Up to 6,000 psi |
NPT, SW, Direct Mount |
|
Butterfly Valve |
2″ – 48″ (DN 50–1200) |
Class 150–600 |
Wafer, Lugged, Double Flanged |
ASME B16.34 Class-to-Pressure Ratings (UNS S32750 @ 20°C)
|
Pressure Class |
Maximum Allowable Pressure |
|
Class 150 |
20.0 bar (290 psi) |
|
Class 300 |
51.1 bar (741 psi) |
|
Class 600 |
102.1 bar (1,480 psi) |
|
Class 900 |
153.2 bar (2,220 psi) |
|
Class 1500 |
255.3 bar (3,705 psi) |
|
Class 2500 |
425.4 bar (6,170 psi) |
Face-to-Face Dimensions (Ball Valve, Flanged, ASME B16.10 — Selected Sizes)
|
NPS |
DN |
Class 150 F-F (mm) |
Class 300 F-F (mm) |
Class 600 F-F (mm) |
|
1″ |
DN 25 |
108 |
124 |
124 |
|
1½” |
DN 40 |
114 |
149 |
149 |
|
2″ |
DN 50 |
127 |
165 |
165 |
|
3″ |
DN 80 |
178 |
210 |
210 |
|
4″ |
DN 100 |
229 |
254 |
254 |
|
6″ |
DN 150 |
394 |
406 |
419 |
|
8″ |
DN 200 |
457 |
495 |
508 |
|
10″ |
DN 250 |
533 |
572 |
597 |
|
12″ |
DN 300 |
610 |
660 |
673 |
Dimensions are indicative; exact dimensions per ASME B16.10. Contact us for dimensions of special classes or custom face-to-face requirements.
Super Duplex Steel Tube Fittings
Chemical Composition — Super Duplex Steel Grades
The corrosion resistance and mechanical superiority of super duplex steel valves flow directly from their chemical composition. Kalpataru sources forged billets from approved mills that meet the composition limits mandated by ASTM A182 for F53 and F55 grades.
UNS S32750 (ASTM A182 F53 — Duplex 2507)
|
Element |
Min % |
Max % |
Typical % |
|
Chromium (Cr) |
24.0 |
26.0 |
25.0 |
|
Nickel (Ni) |
6.0 |
8.0 |
7.0 |
|
Molybdenum (Mo) |
3.0 |
5.0 |
4.0 |
|
Nitrogen (N) |
0.24 |
0.32 |
0.27 |
|
Manganese (Mn) |
— |
1.20 |
0.8 |
|
Silicon (Si) |
— |
0.80 |
0.3 |
|
Carbon (C) |
— |
0.030 |
0.015 |
|
Phosphorus (P) |
— |
0.035 |
0.020 |
|
Sulfur (S) |
— |
0.020 |
0.005 |
|
Iron (Fe) |
Balance |
— |
Balance |
|
PREN Calculated |
≥ 40 |
— |
42–43 |
UNS S32760 (ASTM A182 F55 — Zeron 100)
|
Element |
Min % |
Max % |
Typical % |
|
Chromium (Cr) |
24.0 |
26.0 |
25.0 |
|
Nickel (Ni) |
6.0 |
8.0 |
7.0 |
|
Molybdenum (Mo) |
3.0 |
4.0 |
3.5 |
|
Nitrogen (N) |
0.20 |
0.30 |
0.25 |
|
Tungsten (W) |
0.50 |
1.00 |
0.70 |
|
Copper (Cu) |
0.50 |
1.00 |
0.70 |
|
Manganese (Mn) |
— |
1.00 |
0.60 |
|
Silicon (Si) |
— |
1.00 |
0.30 |
|
Carbon (C) |
— |
0.030 |
0.015 |
|
Phosphorus (P) |
— |
0.030 |
0.020 |
|
Sulfur (S) |
— |
0.010 |
0.005 |
|
Iron (Fe) |
Balance |
— |
Balance |
|
PREN Calculated |
≥ 40 |
— |
40–41 |
PREN = %Cr + 3.3×%Mo + 16×%N. S32760 PREN formula includes tungsten: PREN = %Cr + 3.3×(%Mo+0.5×%W) + 16×%N.
Grade Comparison: S32750 vs S32760 vs S31803 (Standard Duplex)
|
Property |
S32750 (F53) |
S32760 (F55) |
S31803 (F51) |
|
Cr % |
25 |
25 |
22 |
|
Mo % |
4 |
3.5 |
3 |
|
N % |
0.27 |
0.25 |
0.17 |
|
PREN |
42–43 |
40–41 |
30–38 |
|
Classification |
Super Duplex |
Super Duplex |
Standard Duplex |
|
Seawater Resistance |
Excellent |
Excellent |
Good |
Super Duplex Steel S32750/S32760 Pipe Fittings
Mechanical Properties — Super Duplex Steel Valve Materials
The mechanical superiority of super duplex valves over austenitic stainless steels is significant — the tensile strength of UNS S32750 is nearly 60% higher than grade 316L, allowing valve designers to reduce wall thickness and component weight without compromising pressure integrity.
UNS S32750 (ASTM A182 F53) — Mechanical Properties
|
Property |
Requirement (ASTM A182) |
Typical Achieved |
|
Tensile Strength (UTS) |
≥ 795 MPa (115 ksi) |
820–860 MPa |
|
0.2% Proof Stress (Rp0.2) |
≥ 550 MPa (80 ksi) |
575–640 MPa |
|
Elongation (A50) |
≥ 15% |
25–30% |
|
Reduction in Area |
≥ 45% |
55–60% |
|
Hardness |
≤ 310 HB / ≤ 32 HRC |
240–270 HB |
|
Charpy Impact (at −46°C) |
≥ 27 J (average) |
60–80 J |
|
Ferrite Content |
40–60% |
45–52% |
UNS S32760 (ASTM A182 F55) — Mechanical Properties
|
Property |
Requirement (ASTM A182) |
Typical Achieved |
|
Tensile Strength (UTS) |
≥ 750 MPa (109 ksi) |
790–830 MPa |
|
0.2% Proof Stress (Rp0.2) |
≥ 550 MPa (80 ksi) |
565–615 MPa |
|
Elongation (A50) |
≥ 25% |
28–33% |
|
Reduction in Area |
≥ 45% |
52–58% |
|
Hardness |
≤ 310 HB / ≤ 32 HRC |
235–265 HB |
|
Charpy Impact (at −46°C) |
≥ 27 J (average) |
65–85 J |
|
Ferrite Content |
40–60% |
43–50% |
Material vs. Material Comparison — Valve Body Grades
|
Property |
UNS S32750 |
UNS S32760 |
UNS S31803 (Duplex) |
AISI 316L |
|
UTS (MPa) |
795+ |
750+ |
620+ |
515+ |
|
Yield (MPa) |
550+ |
550+ |
450+ |
205+ |
|
PREN |
42–43 |
40–41 |
30–38 |
~24 |
|
Max Cl⁻ temp. |
>100°C |
>100°C |
~80°C |
~50°C |
|
SCC Resistance |
Excellent |
Excellent |
Good |
Poor in chlorides |
|
Cost Index |
1.3× duplex |
1.3× duplex |
0.7× super duplex |
0.4× super duplex |
NACE MR0175/ISO 15156 requires HRC ≤ 36 for all pressure-retaining components in sour service. Both F53 and F55 naturally achieve this in the solution-annealed condition.
Super Duplex Steel S32750/S32760 Flanges
Industry Applications of Super Duplex Steel Valves
Super duplex valves are engineered for service conditions where failure of a valve means not just process downtime but environmental incident, loss of well control, or hazardous release. Their corrosion resistance, mechanical strength, and compliance with international safety standards make them the mandated choice across the following sectors.
Offshore Oil & Gas Production
Subsea and topside production systems expose valves to the trifecta of corrosion challenges: chloride-laden seawater, H₂S-bearing produced fluids, and high pressures. Super duplex valves in UNS S32750 satisfy NACE MR0175 sour service requirements while providing PREN > 40 immunity to chloride pitting — a combination no single austenitic grade can match. Critical applications include:
- Wellhead wing valves and master valves
- Topside production manifolds and pigging valve assemblies
- Injection headers for water, chemical, and gas lift
- Subsea control module instrument valves
- FPSO loading arm isolation valves
Super Duplex Steel Instrumentation Ball Valve
Seawater Reverse Osmosis (SWRO) Desalination
SWRO plants handle concentrated seawater brine at pressures from 60 to 85 bar. At chloride concentrations of 35,000–70,000 ppm, 316L fails catastrophically within months. Super duplex 2507 valves — with PREN typically 42–43 — are the standard of care in:
- High-pressure feed pump suction and discharge valves
- Energy Recovery Device (ERD) isolation valves
- Brine reject throttle and control valves
- Cartridge filter inlet/outlet isolation
- Chemical dosing valve assemblies
Chlor-Alkali and Chlorine Processing
Chlorine-bearing process streams — wet chlorine gas, hydrochloric acid, bleach, and chlorinated solvents — rapidly destroy conventional stainless steels via pitting and uniform corrosion. Super duplex valves in Zeron 100 (UNS S32760) with copper and tungsten additions offer particularly strong resistance to reducing acid environments combined with oxidizing chloride service.
Pulp and Paper Bleach Plants
Kraft bleaching uses chlorine dioxide (ClO₂) in concentrations and temperatures that induce aggressive pitting and SCC in grades below PREN 40. Super duplex ball valves and gate valves in D/EO/D/P bleach sequences reduce maintenance intervals from months to years.
Super Duplex Steel Needle Valve
Geothermal Power Plants
Geothermal brine contains dissolved chlorides, carbon dioxide, and hydrogen sulfide at temperatures from 150°C to 350°C. Super duplex valves handle two-phase steam/brine flow, scaling, and aggressive chemistry at the wellhead separator, brine injection, and reinjection stages.
Pharmaceutical and Biotech CIP/SIP Systems
Clean-in-Place circuits use sodium hypochlorite, peracetic acid, and caustic soda at elevated temperatures. Super duplex valves are specified where 316L surface pitting compromises product purity validation under FDA 21 CFR or EMA standards.
Marine and Naval Systems
Seawater service systems on naval vessels, offshore support vessels, and LNG carriers include fire suppression, ballast water treatment, bilge discharge, and seawater cooling. Super duplex valves in Zeron 100 are immune to the crevice corrosion that forms under gaskets and in cavities where stagnant seawater concentrates.
Super Duplex Steel Manifold Valve
Summary — Super Duplex Valve Applications by Industry
|
Industry |
Specific Service |
Grade Preferred |
|
Offshore Oil & Gas |
Wellhead, manifold, sour service |
UNS S32750 (NACE) |
|
SWRO Desalination |
High-pressure brine, ERD |
UNS S32750 |
|
Chlor-Alkali |
Wet Cl₂, HCl, bleach |
UNS S32760 (Zeron 100) |
|
Pulp & Paper |
ClO₂, bleach sequences |
UNS S32750 / S32760 |
|
Geothermal Power |
Brine injection, steam |
UNS S32750 |
|
Pharmaceutical |
CIP/SIP hypochlorite |
UNS S32750 |
|
Marine / Naval |
Seawater cooling, ballast |
UNS S32760 |
Quality Standards and Certifications
Every super duplex steel valve manufactured at Kalpataru Piping Solution passes through a structured quality assurance process aligned with the world’s most demanding procurement standards. Our quality system is built to satisfy the requirements of major oil and gas operators, EPC contractors, and third-party inspection agencies.
Design and Manufacturing Standards
|
Standard |
Scope |
|
API 6D (latest edition) |
Pipeline and pigging valves |
|
API 608 |
Metal ball valves for petroleum industries |
|
ASME B16.34 |
Valves — flanged, threaded, welding end |
|
MSS SP-72 |
Ball valves with flanged or BW ends |
|
BS 5351 |
Steel ball valves, petroleum industry |
|
API 609 |
Butterfly valves |
|
API 600 |
Steel gate valves |
|
ASME B16.5 |
Pipe flanges and flanged fittings |
|
ASME B16.10 |
Face-to-face dimensions |
|
ASME B16.25 |
Buttwelding ends |
Testing Standards
|
Standard |
Test Covered |
|
API 598 |
Shell hydrostatic, seat closure, and back-seat tests |
|
EN 12266-1 |
Metallic industrial valve pressure tests |
|
ASME B16.34 App. III |
Supplemental high-pressure tests |
|
API 607 |
Fire-safe testing for quarter-turn valves |
|
API 6FA |
Fire test for valves |
|
ISO 15848-1 |
Fugitive emission testing (stem seal) |
Material and Corrosion Testing
|
Standard |
Purpose |
|
ASTM G48 Method A |
Critical pitting temperature (CPT) test in ferric chloride |
|
ASTM G48 Method C |
Critical crevice corrosion temperature (CCT) test |
|
ASTM A923 |
Detection of intermetallic phase (sigma/chi phase) in duplex stainless |
|
NACE MR0175 / ISO 15156 |
Sour service material requirements (H₂S environments) |
|
EN 10204 Type 3.1 |
Mill certificate — standard supply |
|
EN 10204 Type 3.2 |
Third-party witnessed MTC — on request |
Inspection Tests Performed on Every Valve
- Hydrostatic shell test: 1.5× rated pressure for minimum 3 minutes (API 598)
- Low-pressure seat test: Pneumatic air at 6–7 bar (API 598)
- High-pressure seat test: Hydrostatic at rated pressure (API 598)
- Dimensional check: Per ASME B16.34 / B16.10 / B16.5
- Visual and surface inspection: Per MSS SP-55
- Hardness test: All pressure-retaining components per NACE MR0175 (sour service valves)
- PMI (Positive Material Identification): XRF analysis per customer specification
- Radiographic Testing (RT): For cast valve bodies per ASTM E446 when specified
- Liquid Penetrant (PT): Weld seams and machined seat areas per ASME Sec. V
- Ferrite count: By Fischer Feritscope or equivalent on weld areas and heat-treated bodies
Third-Party Inspection Agencies Supported
Bureau Veritas • DNV GL • Lloyd’s Register • TÜV Rheinland • TÜV SÜD • SGS • Intertek • PDIL • EIL • MECON
Our QC department coordinates TPI witness tests, maintains NCR logs, and issues Inspection Release Notes (IRN) before each shipment.
Super Duplex Steel S32750/S32760 Tube Fittings
Why Choose Kalpataru Piping Solution as Your Super Duplex Steel Valve Manufacturer
Procuring super duplex steel valves for a critical project demands more than a catalogue price — it demands a manufacturer with proven metallurgical capability, comprehensive testing infrastructure, and the documentation depth that major oil companies and EPC contractors require. Here is what sets Kalpataru apart.
Deep Expertise in Super Duplex Metallurgy
Super duplex stainless steel is notoriously unforgiving of processing errors. Intermetallic phases (sigma, chi) precipitate between 600°C and 1,050°C and catastrophically reduce toughness and corrosion resistance. Kalpataru’s heat treatment protocol — solution annealing at 1,050–10,100°C followed by rapid water quench with controlled cooling rate — eliminates intermetallic risk. We verify this with ASTM A923 testing and ferrite measurement on every production batch.
Forged-Only Construction for Critical Service
Kalpataru manufactures valve bodies exclusively from forgings (ASTM A182 F53/F55) rather than castings for sizes where forged material is feasible. Forgings provide a refined, aligned grain structure with no porosity, shrinkage, or dendritic segregation — defects inherent to the casting process that reduce corrosion resistance and fatigue life in aggressive service.
Comprehensive In-House Testing Infrastructure
Our test facility is equipped for:
- Hydrostatic testing to 600 bar (8,700 psi)
- Low-pressure pneumatic seat testing
- Hardness testing (Rockwell, Vickers, Brinell) for NACE compliance
- XRF-based PMI on 100% of valves in critical alloy orders
- Ferrite measurement by Feritscope
- Dimensional inspection with calibrated CMM
Fastest Lead Times Among Indian Super Duplex Valve Manufacturers
With a dedicated inventory of UNS S32750 and S32760 forged billets maintained year-round, Kalpataru delivers standard-configuration super duplex valves in 4–8 weeks — significantly faster than the 12–20-week lead times quoted by many European manufacturers for the same material. For urgent requirements, partial air freight is coordinated with the remaining quantity by sea.
Transparent Super Duplex Steel Valve Pricing
We believe procurement teams deserve a clear super duplex steel valve price list rather than opaque budgetary estimates. Our quotations include itemized breakdowns by valve type, size, class, and inspection requirement so your cost engineers can validate landed-cost calculations. We offer FOB Mumbai, CIF, and DDP pricing terms based on project requirements.
Project Documentation Package
Every Kalpataru shipment includes a complete documentation package:
- EN 10204 Type 3.1 Mill Test Certificates (heat and product analysis, mechanical properties, heat treatment record)
- Dimensional Inspection Report (DIR)
- Hydrostatic Test Report (API 598)
- Hardness Test Record (NACE MR0175)
- PMI Report (when specified)
- Packing List, Country of Origin Certificate, and export documents
- Inspection Release Note (IRN) from TPI agency (when applicable)
Global Supply Experience
Kalpataru has supplied super duplex steel valves to projects in the UAE, Qatar, Kuwait, Saudi Arabia, Oman, Norway, the UK, the Netherlands, Singapore, Malaysia, Australia, and multiple African nations. Our logistics team has hands-on experience with SABER (Saudi Arabia), NPC (Norway), UKCA, and other destination-country certification requirements.
Super Duplex Steel UNS S32750 Tubes
Explore the Complete Super Duplex Steel Product Range
|
Product Category |
Link |
|
Super Duplex Instrumentation Ball Valve |
|
|
Super Duplex Needle Valve |
|
|
Super Duplex Manifold Valve |
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Super Duplex Pipe Fittings |
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Super Duplex Flanges |
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Super Duplex Tube Fittings |
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Super Duplex Tubes (S32750) |
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Super Duplex Tubes (S32760) |
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Super Duplex Steel Flanges (Category) |
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Super Duplex Tubes (Category) |
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Super Duplex Steel Tube Fittings |
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Duplex Steel Pipe Fittings |
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All Ball Valves |
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All Needle Valves |
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All Manifold Valves |
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All Gate Valves |
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All Globe Valves |
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All Check Valves |
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Complete Valve Range |
Frequently Asked Questions — Super Duplex Steel Valves
Duplex steel valves (UNS S31803/S32205, ASTM A182 F51) contain approximately 22% Cr, 5% Ni, and 3% Mo, with a PREN of around 30–38. Super duplex steel valves (UNS S32750/S32760, ASTM A182 F53/F55) contain approximately 25% Cr, 7% Ni, and 4% Mo, with a PREN above 40. The higher alloy content provides super duplex valves with better pitting resistance, improved stress corrosion cracking resistance in chloride environments, and higher tensile strength. Super duplex valves are preferred for demanding seawater and high-chloride applications.
PREN stands for Pitting Resistance Equivalent Number and is calculated using the formula %Cr + 3.3 × %Mo + 16 × %N. Super duplex grades generally have a PREN of 40 or higher, compared with approximately 30–38 for standard duplex steel and around 24 for 316L stainless steel. A higher PREN indicates better resistance to chloride-induced pitting, making super duplex valves suitable for seawater, offshore, desalination, and other high-chloride applications.
Kalpataru Piping Solution supplies super duplex steel valves in sizes ranging from 1/4 inch (DN 8) to 24 inches (DN 600) as standard, with larger sizes available on request. Ball valves are available from 1/4 to 24 inches, gate valves from 1/2 to 24 inches, needle valves from 1/4 to 2 inches, manifold valves from 1/4 to 3/4 inch, and butterfly valves from 2 to 48 inches. Pressure ratings can range from ASME Class 150 to Class 2500 depending on valve type and design.
Super duplex steel valve prices depend on valve type, size, pressure class, end connection, material grade, and inspection requirements. As a general indication, instrumentation ball valves may range from approximately USD 100 to USD 500, while standard process ball valves may range from USD 400 to USD 4,000. Larger gate and globe valves can range from approximately USD 6,000 to USD 60,000 or more depending on specifications. NACE compliance, Type 3.2 MTCs, and third-party inspection can increase the final price. Request a project-specific quotation for an accurate price.
UNS S32750, covered by ASTM A182 F53, is a 25Cr-7Ni-4Mo super duplex grade with a typical PREN above 40. UNS S32760, covered by ASTM A182 F55, contains chromium, nickel, molybdenum, nitrogen, tungsten, and copper. Both grades provide excellent resistance to pitting, crevice corrosion, and stress corrosion cracking. The appropriate grade depends on the specific chloride concentration, temperature, chemical environment, and project requirements.
Request Your Super Duplex Steel Valve Price List
Kalpataru Piping Solution is ready to support your project from technical clarification to final delivery. Whether your requirement is a single super duplex ball valve for a pilot plant or a complete valve package for an offshore platform BOM, our team provides detailed technical and commercial proposals within 24–48 working hours.
To get your super duplex steel valve price or project quotation, share:
- Valve type (ball, gate, globe, check, needle, manifold, butterfly, plug)
- Grade (UNS S32750 / ASTM A182 F53 or UNS S32760 / ASTM A182 F55)
- Size (NPS or DN) and pressure class (ASME Class 150 to 2500)
- End connection (flanged RF/RTJ, butt weld BW, socket weld SW, threaded NPT/BSP)
- Applicable design standard (API 6D, API 608, ASME B16.34)
- Actuation (manual, electric, pneumatic, hydraulic)
- Testing and inspection requirements (TPI agency, NACE compliance, API 607 fire safe, Type 3.2 MTC)
- Quantity and delivery port
- Project timeline