Steel Threaded Flanges (TH Flanges) are forged pipe fittings engineered for detachable connection of pipes via internal threading, eliminating the need for welding. Designed with precision-machined internal threads to mate with externally threaded pipes, they form a reliable seal when paired with gaskets and bolted to mating flanges. Key characteristics, specifications, and technical details are as follows:
- Core Definition: A flange with integrated internal threads, designed for threaded connection to externally threaded pipes. Optimized for small-to-medium diameter, low-to-medium pressure systems requiring quick installation, disassembly, and maintenance without welding.
- Structural Features:
- One-piece forged construction – ensures structural integrity, eliminates leakage points from assembly gaps;
- Precision-machined internal threads (standard thread profiles) – guarantees tight fit with threaded pipes, preventing medium leakage;
- Standardized bolt hole patterns and sealing faces – compatible with mating flanges of the same standard;
- Compact design – requires minimal installation space, suitable for confined or weld-restricted areas.
- Material Scope: Forged carbon steel (A105, Q235B), stainless steel (304L, 316L, duplex 2205/2507), alloy steel (A182 F11/F22) – compliant with ASTM, EN, JIS standards, offering excellent corrosion resistance, mechanical strength, and compatibility with various media (liquids, gases, mild chemicals).
- Key Specifications:
- Size Range: DN10 – DN100 (primary small-to-medium bore focus); compatible with NPS 1/2" – 4" and JIS A-series 15A – 100A.
- Pressure Class: PN10 – PN250 / Class 150 – 2500 (optimized for low-to-medium pressure; ultra-high pressure applications require thread integrity verification).
- Thread Types: NPT (National Pipe Tapered), BSPP (British Standard Pipe Parallel), BSPT (British Standard Pipe Tapered) – matched to regional or project thread standards.
- Connection Method: Threaded joint (internal flange threads + external pipe threads) + bolted joint (flange-to-flange with gasket) – no welding required, enabling rapid installation and disassembly for maintenance.
- Core Advantages:
- Weld-free installation – ideal for weld-restricted environments (e.g., explosive, flammable, or precision equipment areas) and reduces welding-related quality risks;
- Detachable design – facilitates pipe maintenance, replacement, or system modification without cutting/damaging pipes;
- Compact and lightweight – suitable for confined spaces (e.g., HVAC ductwork, industrial equipment interiors);
- Forged structure delivers corrosion resistance (adapts to water, oil, mild chemicals) and long service life;
- Cost-effective – lower installation and maintenance costs compared to weld neck or socket weld flanges for small-bore systems.
- Application Scope: Widely used in oil & gas (instrumentation lines, low-pressure branch pipelines), chemical processing (low-pressure reagent lines, batch processing systems), power generation (auxiliary piping, control system lines), marine (shipboard auxiliary piping, HVAC systems), plumbing (building water supply/drainage), and HVAC (heating, ventilation, air conditioning) – preferred for small-to-medium bore, low-to-medium pressure systems requiring welding-free, detachable connections.