Cylindrical forgings   

Specializing in large hollow forged cylinders weighing 1 to 45 tons, our integral forging technology eliminates longitudinal welds, delivering ultimate safety assurance for extreme operating conditions.

Rethinking “Cylindrical Forgings”: Safety Must Never Be Compromised

In extreme operating conditions involving high pressure, high temperature, or severe corrosion, the longitudinal welds of traditional pressure vessel cylinders—formed by rolling and welding steel plates—have always been the weakest link in the reliability chain. Our cylindrical forgings, produced through the “direct forging from solid ingots” process, fundamentally eliminate this longitudinal weld.

This represents not merely a difference in manufacturing methods, but a distinct design philosophy. An integrally forged cylinder features continuous, uninterrupted metal fibers around its circumference, eliminating heat-affected zones and delivering exceptional isotropy. Under identical design parameters, this translates to significantly higher fatigue life, superior resistance to stress corrosion cracking, and unparalleled safety redundancy.

Core Process: The Transformation from Solid Ingots to Precision Thick-Walled Cylinders

Transforming dozens of tons of solid steel ingots into large hollow cylinders represents the ultimate test of process control capability. Our core lies in the precise mastery of metal flow:

Customized Long-to-Diameter Ratio Ingots and Center Compaction

Collaborating with steel mills, we develop ingots with optimized length-to-diameter ratios for cylinder forgings. Forging commences with thorough “center compaction”—multiple upsetting and drawing operations on an 8,000-ton press prioritize density and purity in the ingot's core region (which will form the cylinder's inner wall).

Hollow Punching and Unrestrained Drawing (Core Competitive Edge)

At elevated temperatures, we perform central punching using specialized punches. The subsequent critical step is “unrestrained drawing”—forging on a mandrel that allows metal flow primarily along radial and tangential directions, rather than simple axial elongation.

Technical Achievement: This method achieves more uniform wall thickness distribution and elevates the forging ratio of the inner bore surface to over 3:1. This results in an exceptionally dense inner wall structure, serving as the primary defense against media corrosion and pressure permeation.

Technical Capabilities: The Scale and Precision of Our Manufacturing

Core Applications: Where are seamless cylindrical forgings required?

Our monolithic forged cylinders serve as the backbone for high-end equipment in the following sectors:

Petrochemical Industry: Functioning as core cylinder sections for hydrogenation reactors, coal liquefaction reactors, and high-pressure polyethylene tubular reactors, they operate under high-temperature, high-pressure, and hydrogen-containing conditions with zero tolerance for welds.

Nuclear Power: Used in pressurized water reactor (PWR) steam generator shells, pressurizer cylinders, and reactor pressure vessel (RPV) inlet/outlet nozzle sections, meeting nuclear safety Class 1 equipment requirements.

Energy & Power: Manufactures outer cylinders for ultra-supercritical thermal power units, large-diameter thick-walled steam pipe elbows, and tee blanks, enduring long-term erosion by high-temperature steam.

Heavy Machinery: Serves as prestressed frame cylinders for large extruders and die-forging presses, maintaining dimensional stability under ultra-high cyclic loads.

Why Choose Us: Focus, Transparency, and Mutual Growth

At Zhongfa Flange, we recognize we are not an all-powerful industry giant. Our value stems from two decades of unwavering dedication to the specialized field of cylindrical forgings and the practical expertise we've accumulated—expertise that delivers tangible benefits for you.

1. We never accept orders beyond our capabilities, taking responsibility only for what we can deliver with certainty

The Reality: If your cylinder dimensions or material requirements exceed our equipment and expertise, we will frankly inform you and may recommend a more suitable partner. We believe prudent commitments hold greater value than exaggerated contracts.

Our “Transparent Process” Gives You Peace of Mind

The Reality: Starting from billet feeding, we report progress at key milestones (e.g., after punching or rough machining) via photos or short videos. You won't need to guess the process or visit the site. This is a fundamental respect and the foundation for building long-term trust.

We Value “Ongoing Communication” Over a Perfect Report

The Truth: Your project will be managed by a dedicated team comprising sales, process, and quality control personnel. Any minor anomaly—such as an atypical signal detected during ultrasonic testing that requires evaluation—will be communicated to you immediately. We will collaborate to find solutions rather than conceal issues or handle them unilaterally.

Launching Your Collaboration: Three Steps to Kickstart Your Custom Project

Partner with us for custom tubular forgings through a clear, straightforward process designed to efficiently launch your project.

Step 1: Submit Your Requirements

Send us your technical drawings, specifications, or a brief list of requirements (e.g., outer diameter, inner diameter, length, material, application). Even if you only have a sketch or concept, feel free to reach out.

Step 2: Rapid Assessment

Upon receiving your requirements, our technical sales team will reach out within 24 hours for an initial consultation, providing:

Preliminary process feasibility analysis.

Estimated production capacity and delivery timeline.

Step 3: Detailed Coordination

If the initial proposal meets your expectations, we will schedule a meeting to discuss detailed technical agreements, quality inspection plans, and final quotations, advancing the project into the execution phase.