The outer protective layer of our High-Density Polyurethane Thermal Insulation Pipe is meticulously crafted from robust and resilient high-strength polyethylene material. Leveraging our company's pioneering polyethylene modification technology, the surface of the polyethylene is expertly polarized, significantly enhancing its adhesion performance with polyurethane. This results in a superior, long-lasting bond that ensures unparalleled durability and performance.
| 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: Our selection includes seamless steel pipe, spiral welded pipe, and straight seam welded pipe. Prior to thermal insulation, we ensure the mechanical rust removal level adheres to not less than GB/T8923.1 Sa 2.5 standards.
2. Slepipe: Crafted from specially modified flame-retardant and anti-static polyethylene resin, processed by a single screw extrusion machine. This component boasts exceptional impact resistance, isolation effects, and corrosion resistance.
3. Polyurethane Insulation Layer: Utilizing modified flame-retardant polyurethane foam through high-pressure injection, this layer fills the gap between the casing and the working steel pipe, providing superior insulation. It features low thermal conductivity, high compression strength, low water absorption, and a high closure rate.
1. No support needed, minimal heat loss, eliminating the 'support thermal bridge' phenomenon entirely.
2. High strength and good toughness make it easy to weld and construct efficiently.
3. Low thermal conductivity combined with robust waterproof and corrosion resistance. Suitable for direct burial in the ground or underwater.
4. Easy connection options, including flange and quick joint connections.
5. Long service life, capable of operating in environments ranging from -20ºC to 120ºC for over 30 years.
Insulation steel pipes are pivotal in liquid and gas transmission insulation projects spanning various industries. They are extensively used in petroleum, chemical processing, central heating networks, central air-conditioning ventilation systems, and municipal projects. The high-temperature, prefabricated direct-buried thermal insulation steel pipe stands out with its exceptional thermal insulation properties, ensuring safety, reliability, and cost-efficiency in construction. This innovative solution delivers unparalleled performance, making it the top choice for modern infrastructure and industrial applications.
Shandong Donghong Pipe Industry Co., Ltd. (referred to as: Donghong Co., Ltd., stock code: 603856) is proudly headquartered in Qufu, China, the revered hometown of Confucius. As a premier engineering pipeline manufacturer, service provider, and general contractor, we specialize in four main categories of sophisticated and customized pipelines: specialized pipelines for rainwater and sewage diversion, municipal areas, industrial and mining sectors, and national key engineering projects. Donghong Co., Ltd. has developed an unparalleled industrial ecosystem through strategic collaborations with design institutes, financial institutions, port logistics, construction units, and both upstream and downstream enterprises. Our mission is to become the global leader in comprehensive pipeline system solutions, transforming human life and ensuring the safety of pipeline transportation through intelligent and innovative pipeline systems.
Donghong boasts a robust team of over 200 R&D personnel and holds more than 100 patents. Leveraging our national enterprise technology center, national CNAS laboratory, academician expert workstation, post-doctoral workstation, and other premier R&D platforms, we drive advancements in the digitalization, informatization, and intelligentization of pipeline engineering. Donghong continues to lead and shape the future of the engineering pipeline industry.
In a landmark achievement, Donghong was listed on the main board of Shanghai in November 2017, proudly becoming the first company in China's engineered composite piping system to achieve this milestone.
Exceptional Technical Research and Development Capability
Our national CNAS laboratory, equipped with state-of-the-art testing equipment, is integral to our commitment to innovation. We collaborate on the development of new products, materials, and connection types, alongside rigorous testing of our own products to ensure their stability and reliability, thus guaranteeing superior product quality.
Donghong has established strategic partnerships with more than 5 5A-level logistics companies, and we have many years of transportation experience. Combining automobile transportation, railway transportation, port and shipping logistics, etc., no matter the heat or cold, no matter the area is remote or harsh, we can provide you with the best service. We have a comprehensive transportation strategy to ensure that every shipment is delivered to the customer site as soon as possible.
1. Is your product meets the international standard ?
Our products have passed CE, BV, ISO, and WARS certifications. All our figures indicate performance exceeding the standard requirements. Feel free to inform us of any specific national standards you need, and we will verify or test our products accordingly.
2. What kind of service do you offer ?
As a manufacturing factory, we provide a comprehensive range of pipe products, fittings, packaging, and shipping services. As a professional consulting company, we offer project advisory services, pipe system solutions, and design recommendations. Additionally, as an engineering-focused enterprise, we provide pipeline contracting and repair services along with complimentary maintenance guidance.
3. Do you support OEM/ODM service?
Absolutely! We offer customization in terms of material, specifications, logo, packaging, connection methods, and more. Our expert team can provide tailored solutions for your specific projects, backed by our successful case studies.
4. What's your terms of payment?
We accept T/T or L/C at sight.
5. How can you gurantee the goods you offered is qualified?
We warmly welcome all customers to visit our company and inspect our products firsthand. We can also conduct stringent tests as per customer requirements prior to order placement. Additionally, before commencing bulk production, we can dispatch samples for customers to perform their own quality tests.
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