The outer protective layer is meticulously crafted from high-strength, high-toughness polyethylene material. Utilizing Shandong Donghong Pipe Industry Co., Ltd.'s revolutionary polyethylene modification technology, this layer undergoes a surface polarization process that significantly enhances its adhesive compatibility with polyurethane. This innovative approach ensures superior adhesion performance, providing unmatched durability and efficiency in thermal insulation applications.
| Working Steel Pipe Diameter mm |
Outer Sheath Diameter mm |
Minimum thickness of outer sheath mm |
Insulation layer thickness mm |
| 426 |
494-554 |
4.0 |
30-60 |
| 478 |
547-607 |
4.5 |
30-60 |
| 529 |
598-658 |
4.5 |
30-60 |
| 630 |
700-760 |
5.0 |
30-60 |
| 720 |
790-850 |
5.0 |
30-60 |
| 820 |
891-951 |
5.5 |
30-60 |
| 920 |
992-1052 |
6.0 |
30-60 |
| 1020 |
1093-1153 |
6.5 |
30-60 |
| 1120 |
1194-1254 |
7.0 |
30-60 |
| 1220 |
1316-1436 |
8.0 |
40-100 |
| 1420 |
1538-1678 |
9.0 |
50-120 |
| 1620 |
1760-1880 |
10.0 |
60-120 |
| 1820 |
1960-2080 |
10.0 |
60-120 |
| Note: can be customized as customer's needs. |
1. Working Steel Pipe: Meticulously crafted from premium seamless steel pipe, spiral welded pipe, and straight seam welded pipe. Before thermal insulation, our pipes undergo rigorous mechanical rust removal to ensure a quality standard that meets or exceeds GB/T8923.1 Sa level 2.5, delivering unparalleled reliability and durability.
2. Slepipe: Designed with a proprietary blend of modified flame retardant and anti-static polyethylene resin, processed using advanced single screw extrusion technology. This innovation endows our pipes with exceptional impact resistance, superior isolation properties, and formidable corrosion resistance, making them ideal for demanding applications.
3. Polyurethane Insulation Layer: We employ a cutting-edge modified flame retardant polyurethane foam injected under high pressure to fill the gap between the casing and the working steel pipe. This process creates a superior insulation effect, characterized by exceptionally low thermal conductivity, high compression strength, minimal water absorption, and an impressive closure rate, ensuring optimal thermal performance.
1. Eliminates the need for additional support, significantly reduces heat loss, and completely eradicates the 'support thermal bridge' phenomenon, enhancing energy efficiency.
2. Offers remarkable strength and excellent toughness, coupled with ease of welding and convenient construction, ensuring seamless integration into any project.
3. Exhibits exceptionally low thermal conductivity along with robust waterproof and corrosion resistance properties, making it ideally suited for direct burial in the ground or underwater applications, providing versatility and reliability.
4. Ensures straightforward connection through flange or quick joint connections, simplifying the installation process and reducing labor costs.
5. Boasts an impressive service life, enduring in challenging environments with temperatures ranging from -20ºC to 120ºC for over 30 years, ensuring long-term performance and reliability.
Explore a variety of connection methods that enhance the efficiency and reliability of your operations.
| Flange connection |
Flexible socket connection |
Detailed welding joint demonstration for seamless integration and robust performance.
Insulation steel pipes are indispensable in liquid and gas transmission pipe insulation projects across various sectors such as petroleum, chemical industries, central heating systems, heating networks, central air-conditioning ventilation pipes, and municipal engineering. Our high-temperature prefabricated direct-buried thermal insulation steel pipe stands out as a premier choice, offering exceptional thermal insulation performance, unparalleled safety and reliability, and notably reduced construction costs. Specifically designed to excel in the most demanding conditions, these pipes ensure longevity and efficiency, making them an invaluable asset for industrial and municipal applications alike. By choosing our solution, you are making a wise investment in cutting-edge technology, superior engineering, and sustainable infrastructure.
Shandong Donghong Pipe Industry Co., Ltd. (referred to as: Donghong Co., Ltd., stock code: 603856) is headquartered in the historic city of Qufu, China, famously known as the hometown of Confucius. We are a leading name in the engineering pipeline sector, excelling as a manufacturer, comprehensive service provider, and general contractor. Our core business focuses on four main categories of specialized and customized pipeline solutions: rainwater and sewage diversion, municipal, industrial and mining sectors, and crucial national engineering projects. By creating a robust industrial ecosystem that incorporates design institutes, financial bodies, port logistics, construction firms, and both upstream and downstream enterprises, Donghong Co., Ltd. aims at revolutionizing the global pipeline industry. Our mission is to lead the way with intelligent pipeline solutions that enhance the quality of life and ensure the enduring safety of pipeline transportation.
Donghong takes pride in its team of over 200 R&D experts and an impressive portfolio of more than 100 patents. Our innovation is driven by national technology platforms such as the enterprise technology center, CNAS laboratory, academician expert workstation, and post-doctoral workstation. We are pioneering the digitalization, informatization, and intelligentization of pipeline engineering, driving the industry forward and setting new standards of excellence.
In November 2017, Donghong celebrated a landmark achievement by being listed on the main board of Shanghai, a historic first for engineered composite piping systems in China.
Outstanding Technical Research and Development Capabilities
Our national CNAS laboratory is outfitted with state-of-the-art testing equipment, enabling the development of new products, materials, and connection types. This rigorous testing guarantees that our product quality is consistently stable and reliable, underlining our steadfast commitment to excellence.
Donghong has established strategic partnerships with over five elite 5A-level logistics companies, boasting extensive expertise in transportation. Utilizing a dynamic blend of automobile, railway, port, and shipping logistics, we ensure unparalleled service, regardless of extreme temperatures or challenging locations. Our robust transportation strategy guarantees timely delivery to your site, maintaining the highest standards of efficiency and reliability.
1. Does your product meet international standards?
Our products have not only successfully passed CE, BV, ISO, and WAR certifications but have also exceeded all required standards. Specify the national standard you need, and we will either verify or test it to ensure compliance, guaranteeing the highest quality and reliability.
2. What kinds of services do you offer?
As a manufacturing factory, we offer an extensive range of pipe products, fittings, packaging, and shipping solutions. In our role as a consultancy, we provide expert project consulting, innovative pipe system solutions, and detailed design recommendations. Furthermore, as an engineering-focused enterprise, we excel in pipeline contracting, repair services, and free maintenance guidance, ensuring comprehensive support for all your needs.
3. Do you support OEM/ODM services?
Absolutely, we offer extensive customization options in materials, specifications, logos, packaging, and connection methods. Our expert team is proficient in delivering tailored solutions for your unique projects, backed by numerous successful cases that highlight our exceptional service.
4. What are your terms of payment?
We accept T/T (Telegraphic Transfer) or L/C (Letter of Credit) at sight, providing flexibility and convenience in our payment options.
5. How can you guarantee the quality of your goods?
We warmly invite all customers to visit our company and inspect our goods firsthand. We are also capable of conducting rigorous tests as per your request before the order. Additionally, we can send samples before bulk production for your testing and approval, ensuring the highest quality standards are met for your satisfaction.
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