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. This enhanced adhesion capability not only amplifies the durability but ensures a robust and reliable thermal insulation system, catering to the demanding requirements of both heating and cooling in underground mining operations. By harnessing state-of-the-art engineering and material science, Shandong Donghong Pipe Industry Co., Ltd. sets a new benchmark in pipeline technology, delivering products that promise longevity, efficiency, and peak performance in the most challenging environments.
| 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 pipes are expertly crafted from seamless steel, spiral welded, and straight seam welded pipes. Prior to thermal insulation, each pipe undergoes rigorous mechanical rust removal, ensuring a quality standard that meets or exceeds GB/T8923.1 Sa level 2.5.
2. Slepipe: Designed with a specially modified flame retardant and anti-static polyethylene resin, processed meticulously by a single screw extrusion machine. This grants our pipes remarkable impact resistance, exceptional isolation capabilities, and extraordinary corrosion resistance.
3. Polyurethane Insulation Layer: We employ 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 unrivaled insulation effect characterized by 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 issue of 'support thermal bridge'.
2. Provides exceptional strength and outstanding toughness, featuring easy welding and convenient construction for streamlined installation.
3. Exhibits excellent low thermal conductivity, along with robust waterproof and corrosion-resistant properties, making it ideal for direct burial either underground or underwater.
4. Guarantees simple and efficient connection through flange or quick joint mechanisms.
5. Ensures a long-lasting service life, efficiently operating in environments ranging from -20ºC to 120ºC for over 30 years.
Explore various state-of-the-art connection methods designed to ensure seamless integration and optimal performance.
| Flange connection |
Flexible socket connection |
A closer look at the welding joint demonstration, showcasing precision and durability in every connection.
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. We proudly stand as a premier engineering pipeline manufacturer, comprehensive pipeline engineering service provider, and trusted general contractor. Our core business encompasses 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 seamlessly 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 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 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.
Shandong Donghong Pipe Industry Co., Ltd. has forged strategic alliances with over five elite 5A-level logistics companies, boasting an extensive and seasoned transportation network. Our multifaceted logistics solutions encompass automobile, railway, port, and shipping logistics. Be it scorching heat or freezing cold, remote wilderness or challenging terrains, we are committed to delivering unparalleled service. Our holistic transportation strategy ensures the timely and seamless delivery of every shipment to your specified location, enhancing your operational efficiency and satisfaction.
1. Does your product meet international standards?
Our products proudly meet and exceed international quality benchmarks, having secured CE, BV, ISO, and WAR certifications. Each product surpasses the stipulated standards, ensuring top-notch quality. Feel free to specify any national standards you require, and we will gladly verify or test the product to meet your specific needs.
2. What kinds of services do you offer?
As a leading manufacturing factory, we offer an extensive selection of pipe products, fittings, sophisticated packaging, and efficient shipping solutions. Beyond manufacturing, we excel as consultants, delivering expert project advice, comprehensive pipe system solutions, and insightful design recommendations. Additionally, our engineering prowess allows us to provide pipeline contracting, meticulous repair services, and complimentary maintenance guidance to ensure your systems operate flawlessly.
3. Do you support OEM/ODM services?
Absolutely! We specialize in OEM/ODM services, allowing for customization in materials, specifications, logos, packaging, and connection methods. Our expert team is adept at crafting tailored solutions for your unique projects, with a proven track record of successful implementations to attest to our service capabilities.
4. What are your terms of payment?
We accept payments via T/T or L/C at sight, providing flexibility and convenience for our valued customers.
5. How can you guarantee the quality of your goods?
We extend a warm invitation for all customers to visit our company and inspect our goods firsthand, ensuring complete satisfaction. Additionally, we offer rigorous testing services upon customer request before orders are finalized. To further ensure quality, we can provide samples prior to bulk production for customer testing and qualification, guaranteeing that our products meet your high standards.
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