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 seamless steel pipe, spiral welded pipe, and straight seam welded pipe. Before thermal insulation, each pipe undergoes rigorous mechanical rust removal to meet or exceed the GB/T8923.1 Sa level 2.5 standard, ensuring unmatched quality and durability.
2. Slepipe: Designed with a specially modified flame-retardant and anti-static polyethylene resin, processed through a single-screw extrusion machine. This endows our pipes with outstanding impact resistance, remarkable isolation, and robust corrosion resistance.
3. Polyurethane Insulation Layer: We employ advanced modified flame-retardant polyurethane foam, injected under high pressure to fill the gap between the casing and the working steel pipe. This results in superior insulation, characterized by low thermal conductivity, high compression strength, minimal water absorption, and a high closure rate, setting a new standard in insulation.
1. Eliminates the need for additional support, drastically reduces heat loss, and completely eradicates the phenomenon of 'support thermal bridge,' ensuring efficiency and cost-effectiveness.
2. Offers exceptional strength and excellent toughness, making welding easy and construction convenient. Our pipes are engineered for seamless integration into any system.
3. Provides low thermal conductivity and exceptional waterproof and corrosion resistance, making these pipes ideal for direct burial in the ground or underwater installations.
4. Ensures straightforward connection through either flange or quick joint connections, facilitating easy and reliable installation.
5. Features a remarkably long service life, performing reliably in environments ranging from -20ºC to 120ºC for over 30 years, ensuring enduring performance and peace of mind.
Explore the Various Connection Methods
| Flange connection |
Flexible socket connection |
Detailed Welding Joint Demonstration
Insulation steel pipes are essential for liquid and gas transmission pipe insulation projects spanning multiple industries, including petroleum, chemical sectors, central heating systems, heating networks, central air-conditioning ventilation, and municipal engineering. Our high-temperature prefabricated direct-buried thermal insulation steel pipe shines as a top-tier solution, delivering superior thermal insulation performance, unmatched safety and reliability, and significantly lower construction costs.
Shandong Donghong Pipe Industry Co., Ltd. (referred to as: Donghong Co., Ltd., stock code: 603856) is headquartered in the illustrious city of Qufu, China, the revered hometown of Confucius. As a premier engineering pipeline manufacturer, comprehensive pipeline engineering service provider, and trusted general contractor, we excel in four primary categories of functional and customized pipeline solutions: specialized pipelines for rainwater and sewage diversion, municipal areas, industrial and mining zones, and national key engineering projects. We foster an industrial ecosystem that seamlessly integrates design institutes, financial institutions, port logistics, construction units, and both upstream and downstream enterprises. At Donghong Co., Ltd., we are committed to revolutionizing the global pipeline landscape with our intelligent pipeline solutions that not only enhance the quality of human life but also ensure the perpetual safety of pipeline transportation.
Donghong is proud to have a robust team of over 200 R&D professionals 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 pioneers in the digitalization, informatization, and intelligentization of pipeline engineering, steering the industry's evolution and establishing new benchmarks of excellence.
In November 2017, Donghong marked a significant milestone by being listed on the main board of Shanghai, making history as the first engineered composite piping systems company in China to achieve this honor.
Outstanding Technical Research and Development Capabilities
Our national CNAS laboratory is equipped with state-of-the-art testing equipment, enabling the development of new products, materials, and connection types. This rigorous testing ensures our product quality remains consistently stable and reliable, reflecting our unwavering commitment to excellence.
Donghong has established strategic partnerships with over five elite 5A-level logistics companies, bringing years of unmatched transportation expertise to the table. Utilizing a multifaceted approach encompassing vehicular transport, railway systems, and sophisticated port and shipping logistics, we ensure seamless delivery regardless of weather conditions or geographic challenges. Our comprehensive transportation strategy guarantees that each shipment reaches the customer's site with unparalleled speed and efficiency, offering the best service even to the most remote and demanding locations.
1. Does your product meet international standards?
Our products have triumphantly achieved CE, BV, ISO, and WAR certifications, consistently surpassing the requisite benchmarks. Should you have a specific national standard in mind, we are more than equipped to validate or test accordingly to meet those precise criteria.
2. What kinds of services do you offer?
As a premier manufacturing establishment, we furnish a full array of pipe products, fittings, packaging, and shipping solutions. As a consultancy, we excel in offering project consulting, pipe system solutions, and expert design recommendations. Moreover, as an engineering-centric enterprise, we deliver pipeline contracting, comprehensive repair services, and complimentary maintenance guidance to ensure your systems remain optimal.
3. Do you support OEM/ODM services?
Absolutely, we specialize in customization across materials, specifications, logos, packaging, connection methods, and more. Our seasoned team is adept at crafting bespoke solutions tailored to your project's unique requirements, with a portfolio of successful cases underscoring our exceptional service.
4. What are your terms of payment?
We facilitate payments through T/T or L/C at sight, ensuring a seamless transaction process.
5. How can you guarantee the quality of your goods?
We extend a warm invitation to all customers to tour our facilities and scrutinize our products firsthand. Additionally, we are prepared to conduct rigorous tests as specified by customers prior to order placement. We can also provide samples before commencing bulk production, enabling thorough customer testing and qualification.
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