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 engineered from seamless steel pipe, spiral welded pipe, and straight seam welded pipe. Prior to thermal insulation, each pipe undergoes a rigorous mechanical rust removal process, achieving a quality standard of no less than GB/T8923.1 Sa level 2.5.
2. Slepipe: Designed with a specially formulated modified flame retardant and anti-static polyethylene resin, processed using a state-of-the-art single screw extrusion machine. This endows our pipes with extraordinary impact resistance, superior isolation, and exceptional corrosion resistance.
3. Polyurethane Insulation Layer: Utilizing 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 an unparalleled insulation effect, featuring low thermal conductivity, high compression strength, minimal water absorption, and a superior closure rate.
1. Eliminates the need for support structures, significantly reduces heat loss, and completely eradicates the 'support thermal bridge' phenomenon.
2. Offers exceptional strength and excellent toughness, with easy weldability and convenient construction, making it ideal for diverse applications.
3. Exhibits extraordinarily low thermal conductivity with robust waterproof and corrosion resistance properties, making it perfectly suitable for direct burial in the ground or underwater environments.
4. Ensures seamless connection through flange or quick joint connections, facilitating efficient and reliable installations.
5. Guarantees a long service life, enduring harsh environments from -20ºC to 120ºC for over 30 years, ensuring reliability and performance over decades.
Explore Various Connection Techniques
| Flange connection |
Flexible socket connection |
Detailed Welding Joint Demonstration
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.
Shandong Donghong Pipe Industry Co., Ltd. (referred to as: Donghong Co., Ltd., stock code: 603856) is headquartered in Qufu, China, the revered hometown of Confucius. As a premier engineering pipeline manufacturer, comprehensive pipeline engineering service provider, and trusted general contractor, we lead the industry with our core business encompassing 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. By fostering an industrial ecosystem that integrates design institutes, financial institutions, port logistics, construction units, and both upstream and downstream enterprises, Donghong Co., Ltd. is dedicated to transforming the global pipeline landscape. Our mission is to lead with intelligent pipelines that enhance human life and ensure the perpetual safety of pipeline transportation.
Donghong boasts a team of over 200 R&D professionals and holds more than 100 patents. Our innovation is anchored by prestigious national technology platforms such as the enterprise technology center, CNAS laboratory, academician expert workstation, and post-doctoral workstation. We are at the forefront of researching and advancing the digitalization, informatization, and intelligentization of pipeline engineering, steering the industry's evolution and setting new benchmarks of excellence.
In November 2017, Donghong achieved a significant milestone by being listed on the main board of Shanghai, marking a historic first for engineered composite piping systems in China.
Outstanding Technical Research and Development Capabilities
Our state-of-the-art national CNAS laboratory is equipped with cutting-edge testing equipment, facilitating the development of new products, materials, and connection types. This rigorous testing ensures our product quality remains consistently stable and reliable, maintaining our unwavering commitment to excellence.
Donghong has established strategic partnerships with over five 5A-level logistics companies and boasts extensive transportation experience. Leveraging a multifaceted approach that includes automobile, railway, port, and shipping logistics, we ensure reliable and efficient service in any climate or location, no matter how remote or challenging. Our comprehensive transportation strategy guarantees prompt delivery of every shipment to the customer's site, ensuring satisfaction and reliability.
1. Does your product meet international standards?
Our products proudly meet and surpass international standards, having successfully attained CE, BV, ISO, and WAR certifications. Each metric significantly exceeds required benchmarks. Should you have specific national standards in mind, just let us know, and we will gladly confirm compliance or arrange pertinent tests to ensure full alignment.
2. What kinds of services do you offer?
At Shandong Donghong Pipe Industry Co., Ltd., we offer a holistic suite of services. As a manufacturing powerhouse, we produce an extensive range of pipe products and fittings, alongside meticulous packaging and shipping options. Our consultancy arm provides expert project advice, comprehensive pipe system solutions, and design recommendations. Furthermore, as an engineering expert, we handle pipeline contracting, repair services, and offer complimentary maintenance guidance to ensure your systems run smoothly.
3. Do you support OEM/ODM services?
Absolutely, we specialize in OEM/ODM services! We offer bespoke customization options across materials, specifications, logos, packaging, and connection methods. Our seasoned team excels in crafting tailored solutions for your unique projects, with a track record of numerous successful case studies highlighting our expertise.
4. What are your terms of payment?
We accept payments via T/T or L/C at sight.
5. How can you guarantee the quality of your goods?
We invite all customers to visit our premises and inspect our goods firsthand to ensure complete satisfaction. Additionally, we offer rigorous pre-order testing upon request and can provide samples for customer evaluation before bulk production. Our commitment to quality assurance ensures that every product meets your stringent standards.
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