---
title: Custom Large Diameter Flange Manufacturer & Factory
date: 2025-05-29T02:23:40Z
modified: 2026-08-06T15:01:45Z
permalink: "https://www.longanflange.com/custom-large-diameter-flange-manufacturer-factory/"
type: page
status: publish
excerpt: ""
wpid: 2399
timestamp: 2026-08-06T15:01:45Z
tags: []
---
# Custom Large Diameter Flanges Manufacturer
LONGAN FLANGE, is a custom large flange factory in China. We specialize in manufacturing large diameter stainless steel flanges—custom-made to your specs, forged in-house, and machined with high precision.
- Fange diameter up to 4000 mm
- OEM & drawing-based production
- ASME / ANSI / DIN / JIS / GOST standards available
- Fast delivery & full traceability
[ gET A cUSTOM qUOTE nOW
](#1)
## how to order large flanges
### 1. Define Your Large Flange Project Requirements
LONGAN FLANGE is capable of manufacture flanges **up to 4000 mm**.
- Pressure class & facing type
- Pipe size & connection type
- Specifications & Standard (ASME, ANSI, DIN, JIS, API, AWWA, etc.)
- Quantity needed
### 2. Material Grade
LONGAN FLANGE mainly producing stainless steel large diameter flanges.
- Stainless Steel (SS304, SS316, etc.)
- Carbon Steel
- Alloy Steel
- Duplex & Super Duplex Steel
- Nickel Alloy
- Copper-Nickel
- Cast Iron / Ductile Iron
### 3. Applicable Standards
- ASME large flange
- ANSI large flange
- DIN large flange
- JIS large flange
- AWWA large flange
- API large flange
### 4. Large Flange Types
LONGAN FLANGE provides custom-forged stainless steel flanges built to your exact specs. No matter how unique or oversized, we deliver practical solutions fast. Start your custom project with us today.
- Large diameter blind flange
- Large diameter lap joint flange
- Large diameter plate flange
- Large diameter slip on flange
- Large diameter threaded flange
- Large diameter weld neck flange
- Large diameter socket neck flanges
## What’s Your Custom Large Flange Needs?
### 2. Material Grade
LONGAN FLANGE mainly producing stainless steel large diameter flanges.
- 304 Stainless Steel (SS304)
- 316 Stainless Steel (SS316)
## What’s Your OEM/ODM Needs?
Tell Us Your Needs
### 3. Applicable Standards
- ASME large flange
- ANSI large flange
- DIN large flange
- JIS large flange
- AWWA large flange
- API large flange
- BS large flange
- GOST large flange
## What’s Your OEM/ODM Needs?
Tell Us Your Needs
### 4. Large Flange Types
LONGAN FLANGE provides custom-forged stainless steel flanges built to your exact specs. No matter how unique or oversized, we deliver practical solutions fast. Start your custom project with us today.
- Large diameter blind flange
- Large diameter lap joint flange
- Large diameter plate flange
- Large diameter slip on flange
- Large diameter threaded flange
- Large diameter weld neck flange
- Large diameter socket neck flanges
## What’s Your OEM/ODM Needs?
Tell Us Your Needs
## how we deliver your custom large flange ORDERS
## Custom LARGE FLANGE Design
- With over a decade of experience since 2011, we offer expert design and manufacturing of extra-large flanges tailored to your exact needs. Trust us to deliver precision, reliability, and performance.
- We also accept custom large diameter flange drawings and technical specifications for non-standard flanges.
## LARGE FLANGE Manufacturing
- Forging & Rolling – Heated billet is forged, then rolled into shape under high pressure to ensure strength and durability.
- Welding & Heat Treatment – Precision welding joins components, followed by heat treatment to enhance strength, stress relief, and structural integrity.
- Surface Finishing – Painting, Spraying, Polishing
## LARGE FLANGE Manufacturing
- Forging & Rolling – Heated billet is forged, then rolled into shape under high pressure to ensure strength and durability.
- Welding & Heat Treatment – Precision welding joins components, followed by heat treatment to enhance strength, stress relief, and structural integrity.
- Surface Finishing – Painting, Spraying, Polishing
## Quality Control
We apply **rigorous quality control** at every stage to ensure your large flange meets exact standards:
- Dimensional accuracy and material compliance
- Surface integrity, flatness, and weld quality
- Verified heat treatment performance
With **NDT**, **hardness testing**, and full **traceability**, we guarantee **zero defects** and **high reliability**. Since **2011**, our commitment to **precision and quality** has earned the trust of clients worldwide.
## Reliable Packaging & Delivery
We ensure your custom extra-large flanges are delivered **on time** and in **flawless, damage-free condition**.
- On-time delivery with carefully planned logistics
- Heavy-duty packaging for maximum protection
- Specialized freight partners for oversized cargo handling
- Export-ready documentation for smooth global shipping
We deliver with **precision**, **protection**, and **professionalism**—every time.
## Reliable Packaging & Delivery
We ensure your custom extra-large flanges are delivered **on time** and in **flawless, damage-free condition**.
- On-time delivery with carefully planned logistics
- Heavy-duty packaging for maximum protection
- Specialized freight partners for oversized cargo handling
- Export-ready documentation for smooth global shipping
We deliver with **precision**, **protection**, and **professionalism**—every time.
CONTACT LONGAN FLANGE
Request a Quote from Experienced Large Flange Manufacturer – LONGAN FLANGE
- No drawing? No problem. Just tell us the size and specs
- Fast quoting within 24 hours — even for small orders
- Stainless steel materials, custom faces, and bolt holes supported
- MOQ starts from 1 piece
**Email:** mft@longanflange.com**Phone:** +86-15727821389
## ABOUT LONGAN FLNGE
Your Trusted Supplier for Custom Large Diameter Flanges – Forged, Machined, and Inspected In-House
https://www.youtube.com/watch?v=hjUaVAy-\_dk&pp=ygUNbG9uZ2FuIGZsYW5nZQ%3D%3D
Longan Flange is a dedicated flange factory with 25+ years of experience. We specialize in **custom stainless steel flanges up to 157 inches**, covering ASME, DIN, JIS, and EN standards.
All flanges are **forged, machined, and inspected in-house**, ensuring precision, fast delivery, and full compliance. Our products serve oil & gas, chemical, and water systems in over 50 countries.
[ Tell Us Your Project
](#1)
## Certifications
Our large flanges are manufactured under strict quality control and comply with major international standards. We provide full certification, including **ISO 9001, CE, ASME, ANSI, DIN, JIS, etc.**, to support your project documentation and regulatory needs.
## Exhibition
We actively participate in major industry exhibitions worldwide to connect with engineers, distributors, and project buyers face-to-face. Visit our booth to explore our custom flange solutions and discuss your project needs directly with our team.
## View OUR Customization Capability
LONGAN FLANGE specializes in producing non-standard, highly customized forged stainless steel fanges tailored to your specific needs. From concept to creation, we turn unique challenges into practical solutions. Contact us to start your custom large flange project.
## Where Our Flanges Are Used
Our large diameter flanges are engineered for demanding environments — from oil & gas pipelines and chemical processing plants to water treatment, mining, and power generation projects. With custom sizes and materials, we deliver solutions that meet real-world engineering challenges.
## Pipeline Connections
## Chemical/Petrochemical Plants
## Water Treatment/Distribution
## Food, Pharmaceutical Industries
## get your custom large flange solution Right now!
[ Request Free Quote
](#1)