ASTM API Manual GATE Valve 304 Stainless Steel Forging 2in Flange Type 150Lb Forged Steel Gate Valve

Specification

Forged Steel and Stainless Steel Wedge Gate Valves: Precision Fluid Control Solutions for High-Pressure Applications

I. Product Overview

As a critical shut-off and regulation device in industrial pipeline systems, TIANYU forged steel and stainless steel wedge gate valves are constructed from high-strength A105 forged carbon steel and 304/316 stainless steel, combined with a wedge-type single gate structure. Specifically engineered for high-pressure, high-temperature, and corrosive environments in petroleum, chemical, power, and metallurgy industries, these valves enable precise on-off control via manual, electric, or pneumatic actuation. Suitable for temperature ranges from -29°C to 425°C and pressure classes from PN16 to PN160 (Class 150 to Class 900), with nominal diameters from DN15 to DN600, they are compatible with various media such as oil-gas, steam, and acid-base solutions, complying with international standards like API 600 and ASME B16.34.

II. Core Features: Dual Technical Breakthroughs in Material and Structure

High-Performance Material Combination
- A105 Forged Carbon Steel: Subjected to 1100°C high-temperature forging and normalizing-tempering treatment, achieving tensile strength ≥485MPa, grain size up to Grade 6, and impact toughness 30% higher than cast steel components. Ideal for high-temperature and high-pressure steam pipelines (e.g., main steam systems in thermal power plants).
- 304/316 Stainless Steel: Using AISI 304 (0Cr18Ni9) or 316 (0Cr17Ni12Mo2) materials, passing intergranular corrosion tests (ASTM A262 E method). The 316 grade resists corrosion from seawater with chloride content ≤200ppm and molybdenum-containing media, suitable for offshore platforms and chemical pickling lines.
Wedge-Type Sealing System Design
- Metal Hard Seal: The gate and seat sealing surfaces are overlay welded with Stellite alloy, hardness ≥HRC55, and precision ground to surface roughness Ra≤0.8μm, meeting API 598 bubble-tight standards (leakage ≤0.01×DN mm³/s).
- Back-Seal Structure: The stem uses trapezoidal threads with flexible graphite packing. When the valve is fully open, medium pressure assists in enhancing sealing to prevent external leakage, ensuring operational safety (complying with ISO 15848-1 low-leakage standards).
Structural Optimization and Operational Performance
- Outside Stem and Yoke (OS&Y): Visually indicates the opening/closing status via stem extension. Combined with a copper alloy nut and molybdenum disulfide grease, it reduces opening/closing torque by 25%, with manual operation force ≤200N·m (DN100 specification).
- Pressure Self-Tightening Bonnet: In high-pressure conditions (e.g., above PN100), medium pressure pushes the bonnet to automatically compress the sealing gasket, avoiding leakage risks from bolt fatigue and enhancing system reliability.
Full Working Condition Adaptability
- Temperature Range: From -29°C low-temperature liquefied natural gas (LNG) pipelines (A105 material passes -46°C low-temperature impact test with impact energy ≥27J) to 425°C high-temperature thermal oil systems (stainless steel maintains oxidation resistance for ≥1000 hours).
- Pressure Class: From PN16 low-pressure steam pipelines to PN160 high-pressure hydrogenation units, customizable forged steel or stainless steel material combinations balance strength and corrosion resistance.

III. Key Attributes: Technical Parameters and Standard Compliance

Attribute Category	Specific Parameters
Nominal Diameter Range	DN15~DN600 (1/2″~24″), supporting non-standard customization (minimum DN10, maximum DN800)
Pressure Class	PN16/25/40/63/100/160 (corresponding to Class 150/300/600/900/1500/2500)
Body Material	A105 forged carbon steel (high-temperature/high-pressure), 304 stainless steel (general corrosion resistance), 316 stainless steel (acid/alkali/seawater resistance)
Seal Material	Stellite alloy (metal hard seal), PTFE (soft seal, -40°C~260°C), reinforced graphite (high-temperature seal)
Actuation Method	Manual (gear-driven), electric (intelligent actuator), pneumatic (double-acting cylinder), hydraulic (high-pressure scenarios)
Connection Type	Flange (RF/RTJ face), welding (BW butt weld), thread (NPT/PT), compliant with ANSI B16.5, GB/T 9113 standards
Execution Standards	Design: API 600, ASME B16.34; Testing: API 598, ISO 5208; Materials: ASTM A105, A351
Suitable Media	Crude oil, natural gas, superheated steam, acid-base solutions, liquefied petroleum gas (LPG), seawater, etc.

Product Overview

IV. Manufacturing Processes: Full-process Precision Control from Forging to Finished Product

Forging and Heat Treatment Processes
- A105 Forging: Steel ingots are forged by a 3000-ton hydraulic press, eliminating internal defects through upsetting-drawing processes. Forgings undergo ultrasonic testing (UT) to ensure no defects ≥2mm equivalent diameter.
- Stainless Steel Forming: 304/316 materials use precision casting or forging processes. Castings undergo solution treatment (1050°C holding + water quenching) to enhance corrosion resistance, with grain size ≥Grade 5.
- Heat Treatment Control: A105 valve bodies are normalized at 900°C + tempered at 650°C, hardness controlled at HB170~220; stainless steel components undergo stress relief annealing to reduce machining deformation risks.
Precision Machining and Surface Treatment
- Seal Surface Machining: Using 5-axis CNC grinders, valve seats and gates are ground in pairs with parallelism error ≤0.01mm, forming high-precision seal pairs.
- Stem Treatment: Surface chrome plating (thickness 0.02~0.05mm) or ceramic coating, hardness ≥HRC60, wear resistance increased 5 times, ensuring 100,000 cycles without jamming.
- Anti-Corrosion Treatment: Stainless steel valve bodies are electropolished (Ra≤0.2μm), A105 valve bodies are sprayed with epoxy resin (thickness ≥200μm), passing salt spray tests ≥1000 hours without rust.
Quality Control System
- Material Traceability: Each batch of steel provides chemical composition analysis (e.g., A105’s C≤0.35%, Mn 0.6~1.05%) and mechanical property reports (yield strength ≥250MPa).
- Pressure Testing: Shell pressurized to 1.5x nominal pressure (e.g., 6.0MPa for PN40 valves) for 15 minutes with no visible leakage; seal testing pressurized to 1.1x nominal pressure for 5 minutes with zero leakage.
- Nondestructive Testing: Welding interfaces undergo 100% radiographic testing (RT), forged components magnetic particle inspection (MT), and key dimensions 100% coordinate measuring (accuracy ±0.02mm).

Valve Details

V. Product Advantages: Core Competitiveness in Harsh Conditions

High-Pressure Reliability and Long Life
Forging processes eliminate material porosity, doubling fatigue life compared to cast steel valves. Data from a refinery hydrogenation unit shows TIANYU stainless steel gate valves operating stably for 8 years in 10MPa, 300°C hydrogen media with no seal failures.
Customized Solutions
- Material Customization: Flexibly configured based on medium corrosiveness (e.g., 316L + hard alloy overlay for H₂S-containing conditions) and temperature-pressure (cryogenic types use nickel-based alloy seals).
- Functional Expansion: Optional anti-static devices (conductive paths between stainless steel components), fire-safe structures (API 607 certified, maintaining sealing for 30 minutes during fires), and signal feedback modules (4~20mA opening output).
Efficiency and Cost Balance
The wedge structure reduces the flow resistance coefficient (Cv value 10% higher than similar products), minimizing pipeline pressure drop; modular design shortens replacement time for vulnerable parts like seals and stems by 50%, reducing maintenance costs by 30%.
Global Service Support
Products are certified by API, CE, and SGS, compatible with multi-national standards; 7×24-hour technical response, 48-hour delivery for regular accessories, and on-site installation debugging for overseas projects ensure project cycles.

Application

VII. TIANYU Brand Customization Advantages: Deep Integration of Technology and Service

As a national brand with 15 years of expertise in high-pressure valves, TIANYU relies on its Tianjin intelligent manufacturing base and national enterprise technology center to provide global customers with customized services from working condition analysis to full lifecycle management. Core brand advantages include:

Technical Expertise: Holding 23 valve invention patents, the self-developed “gradient heat treatment process” increases A105 valve body strength by 15% and reduces thermal expansion coefficient by 8%, applied in key projects like Shenhua Ningxia Coal and Saudi Yanbu.
Flexible Manufacturing: Equipped with 1000-ton forging lines and intelligent machining centers, supporting custom orders from 1 piece, with regular products delivered in 15 days and urgent orders expedited within 72 hours.
Quality Traceability: Each valve is embedded with an RFID chip, scanning to view full-process data from steelmaking to testing, achieving 100% traceability of material batches, processing parameters, and inspection reports.
Global Adaptation: Exported to over 50 countries, validated in harsh conditions at Russia’s Arctic LNG project and Qatar World Cup venue heating systems, providing multilingual technical documentation and localized services.