Carbon Steel Molded Pipes

Overview

Anhui Xinfulong's carbon steel molded pipes are engineered for demanding corrosive fluid handling applications across semiconductor, chemical, pharmaceutical, and new energy industries. Using carbon steel as the load-bearing substrate and lined with high-performance fluoropolymers (PTFE or PFA) through a precision compression molding and sintering process, our molded pipes combine the mechanical strength of carbon steel with the exceptional corrosion resistance, thermal stability, and high purity of fluoropolymer linings--2.

This hybrid construction delivers a reliable, long-lasting piping solution capable of withstanding aggressive chemicals, elevated temperatures, vacuum conditions, and high operating pressures — making it the preferred choice for critical process lines in the most demanding environments.

Product Structure

The carbon steel molded pipe features a dual-layer design engineered for optimal performance:

• Outer Layer (Carbon Steel Substrate) — Provides structural strength, pressure resistance, and mechanical durability. Available in Q235 carbon steel or stainless steel (304/316L) to meet different application requirements.

• Inner Layer (Fluoropolymer Lining) — Precision-molded PTFE or PFA lining offers superior chemical resistance, non-stick surface properties, and ultra-high purity. The lining is fully fused and seamlessly bonded to the steel substrate-.

• Flange Connection — Flanged ends with PFA/PTFE over-molding create a fully sealed, leak-proof connection. Raised face (RF) flange design ensures reliable sealing without the need for gaskets.

Manufacturing Process

Our carbon steel molded pipes are produced using a compression molding and sintering process that ensures superior lining integrity:

1. Surface Preparation — Carbon steel pipes and flanges are welded, then sandblasted to Sa2.5 grade to remove rust, scale, and contaminants, ensuring optimal bonding.

2. Molding — High-purity PTFE or PFA powder is precision-compressed into the steel pipe interior using custom-designed molds and hydraulic pressing.

3. Sintering — The molded assembly undergoes controlled high-temperature sintering, fusing the fluoropolymer lining into a dense, void-free layer that tightly adheres to the steel substrate.

4. Flange Over-Molding — Flange faces are over-molded with fluoropolymer, creating a seamless, self-sealing surface that eliminates leak paths

5. Quality Inspection — Each pipe undergoes dimensional inspection, thickness measurement, and pressure testing to verify performance and integrity.

This process enables the production of large-diameter pipes and complex geometries such as elbows, tees, and reducers with seamless, fully integrated linings — no welds, no joints, no weak points.

Key Features

• Superior Corrosion Resistance — PTFE/PFA lining is chemically inert to virtually all acids, alkalis, organic solvents, strong oxidants, and corrosive chemicals. Only molten alkali metals and elemental fluorine are not recommended.

• Wide Operating Temperature Range — PTFE-lined pipes operate from -50°C to +240°C-; PFA-lined pipes extend to -50°C to +260°C (short-term up to 280°C), significantly outperforming many alternative materials.

• High Pressure and Vacuum Capability — Withstands operating pressures up to 2.5 MPa and vacuum levels down to -0.098 MPa without liner delamination. Available in pressure ratings from PN1.6 to PN2.5, with custom designs for higher requirements.

• Seamless, Leak-Proof Construction — The molded, one-piece lining has no seams, no welds, and no joints — eliminating common failure points found in fabricated linings. Flange faces are fully over-molded for a reliable, gasket-free seal.

• Ultra-High Purity & Low Extractables — The dense, non-porous lining surface prevents contamination of process media. Meets FDA food-grade and semiconductor high-purity requirements.

• Non-Stick, Low Friction Surface — PTFE/PFA's inherently low friction coefficient (≈0.001) minimizes pressure drop, reduces pumping energy consumption, and prevents scale buildup and fouling.

• Excellent Permeation Resistance — The dense, void-free lining structure provides strong resistance to gas and liquid permeation, including oxygen, carbon dioxide, chlorine, and hydrogen chloride.

• Long Service Life — With excellent weatherability and aging resistance, our molded pipes deliver a service life of 8–10 years under normal operating conditions.

Technical Specifications

Applications

Carbon steel molded pipes are widely deployed across industries requiring reliable, corrosion-resistant fluid transport:

• Semiconductor Manufacturing — Ultra-pure chemical delivery, wet etching, wafer cleaning, and advanced node chemical distribution

• Wet Electronic Chemicals — Transport of high-purity acids, solvents, and corrosive chemicals

• Chemical Processing — Pickling lines, acid recovery systems, chlor-alkali processes, and mixed corrosive media handling

• Pharmaceutical & Biotech — High-purity fluid transfer with zero contamination risk; FDA-compliant applications

• New Energy — Battery chemical handling and photovoltaic wet processing

• Fine Chemicals & Environmental Engineering — Strong acid and alkali transport, waste treatment systems

Available Configurations

In addition to straight pipes, we offer a comprehensive range of molded piping components:

Why Choose Xinfulong Carbon Steel Molded Pipes?

• Superior Alternative to Conventional Linings — Our molded construction eliminates weld seams and joints found in fabricated linings, significantly reducing leak points and extending service life.

• Cleanroom Manufacturing — Critical production processes are carried out in Class 1000/10,000 cleanrooms, ensuring the highest levels of purity.

• Proven Global Track Record — Trusted by clients across Europe, Japan, Korea, Taiwan (China), and beyond.

• Comprehensive Quality Assurance — ISO 9001, ISO 14001, ISO 45001 certified with full in-house testing capabilities.

• Industry-Leading Expertise — Backed by decades of fluoropolymer processing experience and R&D collaboration with Japanese and Korean experts.

• End-to-End Service — From custom design and material selection to manufacturing, testing, and after-sales support.

Customization Options

We offer fully customizable carbon steel molded pipes to meet your specific process requirements:

• Custom diameters (DN20–DN500+)

• Custom lining thicknesses (3–10 mm)

• Substrate material options (carbon steel Q235, stainless steel 304/316L)

• Fixed or loose flange configurations

• Multiple flange standards (HG, GB, ANSI, JIS, DIN)

• Custom pipe lengths up to 6,000 mm

• Special configurations for complex geometries

• Lining materials: virgin PTFE, conductive PTFE, PFA