Company Profile
Our History
Established on September 18, 2002, our factory has specialized in the casting of ductile iron municipal components for 24 years. Strategically located in Changxing, Zhejiang - at the junction of Zhejiang, Jiangsu, and Anhui provinces - we benefit from an exceptional logistical location and stand as a long-standing, professional domestic foundry. Initially focused on processing basic iron castings, we registered our proprietary "Dingjian" brand in 2008 and have maintained online operations for 18 years. We continuously refine our casting and anti-corrosion processes and upgrade our customized production systems; our fixed assets exceed RMB 20 million, and we maintain a stable workforce of 11–50 employees, comprising a comprehensive team of casting technicians, structural designers, quality control engineers, and foreign trade specialists. While we originally focused on domestic municipal projects, we have since developed robust capabilities for overseas custom production, supporting orders based on customer drawings or samples, as well as full-service (labor and material) manufacturing. We offer private-label (OEM) services with a minimum order quantity of just 50 units and possess the mature production capacity to handle large-scale overseas infrastructure orders, consistently supplying high-quality, cost-effective ductile iron manhole covers and drainage grates to international contractors and building material traders.
Our Factory
The facility is located in Caojiaqiao Village, Changxing County, Huzhou City, Zhejiang Province, with immediate access to expressways and national freight highways. Its proximity to major foreign trade ports - such as Shanghai, Ningbo, and Zhapu - facilitates efficient logistics, significantly reducing shipping times and maritime transport costs for overseas orders. The plant is organized into six standardized functional zones: raw material melting, sand casting, precision machining and grinding, anti-corrosion coating, finished product warehousing, and a dedicated laboratory for foreign trade custom prototyping. It also features an independent quality inspection laboratory and a dedicated storage area for export-ready goods. Certified under the ISO9001 international quality management system, the facility operates as a standardized, export-oriented foundry, implementing rigorous quality control protocols throughout the entire production process to meet the stringent standards required for overseas engineering projects. The factory specializes in custom manufacturing products with complex geometries or specific load-bearing requirements, utilizing an in-house mold workshop for rapid mold creation and prototyping. It maintains an inventory of 48 standard product models and can complete production for typical small-batch orders within 3 to 7 days. Dedicated personnel manage foreign trade orders, handling everything from packing and load securing to the preparation of customs documentation; the team also facilitates third-party inspections requested by overseas clients, ensuring a stable and reliable export process.
Our Product
Our factory's "Dingjian" brand offers a comprehensive range of ductile iron municipal drainage components, all customizable to the EN124 international load standard. Dimensions, patterns, markings, and anti-corrosion coatings can be tailored to meet specific infrastructure requirements across different regions. Our core product lineup includes: square and round ductile iron manhole covers (covering load classes A15 through D400, with options for anti-subsidence, anti-theft, and noise-reduction features, suitable for stormwater, sewage, power, and telecommunications networks); various specifications of stormwater grates, drainage channel grates, and extra-wide bridge drainage covers (including single-row and double-row linear composite grates); DN300 spherical overflow manholes and 3D permeable collection grates; complete sets of composite manhole covers with frames and cable trench covers; heavy-duty anti-slip road covers and lightweight covers for residential landscaping; and integrated castings for manhole rings. All products are manufactured from high-toughness ductile iron, ensuring resistance to crushing and corrosion as well as high fracture resistance; they come standard with an anti-rust asphalt coating. We support OEM services - including custom branding and municipal utility labeling - and offer mixed-load container shipping to satisfy the one-stop procurement needs of overseas traders.
Product Application
Our ductile iron manhole covers and gratings are designed for urban infrastructure, real estate development, and transportation projects worldwide. They meet the diverse climate and road load requirements of regions such as Europe, the Americas, Southeast Asia, the Middle East, and Africa, while strictly adhering to the international EN124 standard for road construction materials. Applications include: municipal infrastructure (urban arterial roads, highway frontage roads, non-motorized lanes, pedestrian walkways, bridges and tunnels, "Sponge City" stormwater overflow systems, and underground utility inspection chambers for water supply/drainage, power, gas, and telecommunications); commercial real estate (residential complexes, commercial plazas, hotel grounds, and underground garages or landscape drainage systems for villa communities); public works (schools, hospitals, industrial parks, logistics and warehousing hubs, and large open-air parking lots); transportation hubs (port service areas, small airport access roads, and highway stormwater/sewage separation upgrades); and specialized environments (permeable overflow systems for rainy tropical regions, heavy-load roads in mining and industrial zones, and decorative paving in scenic areas). Products can be customized to local vehicle load standards - ranging from light-duty to heavy-duty - and feature high-temperature and salt-alkali resistance, making them suitable for challenging overseas environments such as coastal and desert regions.
Our Certificate
The company possesses full qualifications for compliant operations and a comprehensive export certification system; it holds valid business registration and has publicly disclosed 13 consecutive years of annual reports. Having passed the rigorous 1688 factory audit, the company can provide a complete set of qualification documents for overseas project tenders and approval processes. It holds ISO9001 international quality management system certification, with standardized control across all production stages; all products come with third-party test reports covering load-bearing and corrosion resistance, complying with the international EN124 construction material standard. Regarding intellectual property, the company owns the registered trademark "Dingjian" and holds two patents for structural improvements to cast-iron manhole covers-optimizing designs to prevent subsidence, noise, and displacement, thereby meeting the demands of long-term use on overseas roads. The facility holds a formal foundry production license and can assist overseas clients in preparing a full suite of export documentation, including SGS material test reports, material certificates, packing lists, and commercial invoices. With complete tax and credit records, the company has a long history of collaborating with foreign trade firms and overseas buyers to prepare customs clearance documentation; its products have repeatedly passed on-site inspections by overseas third-party agencies, demonstrating the qualifications to reliably undertake overseas government municipal tenders.
Production Equipment
The factory features an integrated, end-to-end ductile iron casting production line; by handling every stage - from raw material melting, molding, and precision machining to anti-corrosion treatment and quality inspection - in-house without outsourcing, we ensure consistent quality and reliable delivery schedules for overseas orders. The melting section is equipped with medium-frequency electric furnaces and sand casting equipment to precisely control the ductile iron's microstructure, thereby enhancing weather and compression resistance to meet international standards for heavy-duty roadways. The mold workshop utilizes CNC machine tools to rapidly fabricate custom-shaped manhole covers and grates with artistic patterns tailored to overseas clients. Precision machining equipment - including grinding, cutting, and punching machines - ensures accurate processing of gaps and edge dimensions, meeting strict international installation tolerances. The anti-corrosion workshop employs a high-temperature asphalt spraying line, applying a thickened rust-proof coating suitable for coastal environments with high salt-spray exposure. The quality inspection laboratory is equipped with load-bearing testers, salt-spray corrosion testers, and precision dimensional measuring instruments, with inspection reports issued based on sampling from every batch. Finally, the warehouse is outfitted with overhead crane loading/unloading systems to facilitate the rapid loading and securing of full container shipments, efficiently handling large-volume overseas orders.
Production Market
The market is centered on domestic offline engineering channels and relies on Changxing's location to radiate to the core areas of the Yangtze River Delta, Jiangsu, Zhejiang, Shanghai and Anhui.
It is a long-term designated supplier for municipal units, general construction contractors, and building materials wholesalers in Jiangsu and Zhejiang. It accounts for more than 60% of the supply of local municipal renovation and community new construction projects, and cooperates with thousands of engineering companies and building materials stores.
Expand the national market online, covering all provinces and cities in East China, South China, North China, and Southwest China. The average monthly product sales is stable at more than 600 pieces. Regular spot goods are shipped within 48 hours. Long-distance logistics lines go directly to all provinces, and we undertake various municipal and real estate bidding batch orders across the country.
In terms of historical performance, Dingjian brand products have been rated as high-quality products for key projects in Zhejiang Province. They have been supplying rainwater and sewage diversion and old community renovation projects on urban roads in the Yangtze River Delta for a long time. They have participated in the supply of regional municipal road renovation projects for many times.
The company supports batch procurement of domestic projects, with large quantities being preferred and long-term Cooperating customers can enjoy tiered wholesale prices; currently we are not accepting foreign trade export orders, and all our production capacity is focused on the domestic infrastructure market.
With stable quality, low prices directly from manufacturers, and fast customized delivery, we have accumulated a large number of repeat purchase project customers, and our reputation in the regional market is firmly among the top cast iron manhole cover manufacturers in northern Zhejiang.
Our Service
Pre-sales Service
We assign professional technical consultants for one-on-one support, offering free consultations on product specifications, load-bearing selection, and dimensional planning; we recommend suitable manhole cover or grate models based on traffic types and site conditions. We provide rapid quotes based on customer drawings or samples and offer free project supply plans. Customization is available for orders of 50 units or more (based on drawings or samples), including options for engraving logos, utility markings, or city names; we also provide qualification documents for project bidding.
In-sales Service
Production begins immediately upon order confirmation; standard stock items are dispatched within 48 hours, while progress on custom orders is communicated in real-time. During production, we share actual workshop photos and sample images for customer approval. For large orders, we prepare stock in batches and coordinate dedicated logistics vehicles for direct delivery to the site, minimizing transit damage. We track loading and logistics throughout the process and provide shipping documentation promptly.
After-sales Service
We offer a 7-day exchange policy and provide unconditional replacements for products with casting defects or dimensional errors. Post-delivery, we provide technical installation guidance and answer questions regarding road surfacing and frame installation. Long-term partners enjoy a dedicated support channel with a 2-hour response time. We offer an extensive product warranty; for non-human-induced damage occurring during normal outdoor use, we negotiate appropriate after-sales solutions. We also provide ongoing support for restocking and design modifications, ensuring a seamless, one-stop procurement experience.