Located in the heart of China's industrial hub, Ningbo, NJMM leverages a world-class supply chain. With 12 automated pressure welding lines and 6 robotic banding stations, we achieve a scale that reduces lead times by 30% compared to local regional manufacturers.
Our annual output of 50,000 metric tons ensures price stability and stock availability for massive infrastructure projects.
Selection of bar thickness (3mm to 10mm) and depth (20mm to 100mm) is critical. For high-traffic industrial walkways, sizes like JG325/30/100 (32mm depth, 5mm thickness) offer the optimal strength-to-weight ratio, reducing the load on supporting steel structures.
We provide deep analysis on spacing configurations to meet specific drainage and safety requirements.
Every panel manufactured by NJMM complies with ISO9001:2015, CE, and GHOST standards. We were pivotal in drafting the YB/T4001-2019 Chinese steel grating standard, ensuring that our "standard sizes" align with global ASTM and British Standards (BS).
Procurement officers and structural engineers aren't just looking for "metal grids"—they are looking for compliance, safety, and logistical ease. At NJMM, we bridge the gap between Chinese manufacturing efficiency and local site requirements in Europe, South America, and the Middle East.
High corrosion resistance. Recommended: JG405/30/100
Lightweight/Anti-slip. Recommended: Aluminum I-Bar
Ventilation & Load capacity. Recommended: G505/30/100
The industry is shifting toward Intelligent Fabrication and Green Steel. NJMM is at the forefront of this transition:
The most widely used standards are JG255/30/100 and JG325/30/100. The first number (25 or 32) refers to the load bar height, the second (5) to thickness, and the subsequent numbers to the spacing of load bars and cross bars respectively.
Hot-dip galvanization (HDG) provides a metallurgical bond between the zinc and steel. In moderate environments, it can prevent rust for over 50 years, and 20-25 years in harsh industrial or marine coastal environments.
Yes. NJMM operates two specialized irregular grating fabrication platforms. We can manufacture gratings based on your CAD drawings to ensure a perfect fit around pipes, columns, and equipment.
Ensure the manufacturer holds ISO9001 for quality management, CE for European market access, and check if they participate in national standard drafting, which indicates high-level industry expertise (like NJMM's role in YB/T4001).
The serrated surface provides significantly higher slip resistance (rated R10 to R13), which is essential in environments where oil, water, or ice may be present on the walking surface.
Ningbo Jiulong Machinery Manufacturing Co., Ltd (NJMM) was founded in 1993, is mainly engaged in the design and manufacturing of steel grating, railings, platforms and other light steel structures. It is a modern comprehensive enterprise integrating scientific research and design, machinery manufacturing and engineering construction.
We currently have 2 production bases in the East and North of China, there are 12 steel grating auto welding product lines, as well as complete auxiliary processing equipment and testing facilities, like robots welding, laser cutting, digital control panel tailoring etc. Our annual output of steel gratings and allied products, including trench covers, stair treads, stanchions, handrails, fences, is over 50,000 metric tons.
NJMM offers engineering service and support, including the design and installation of the grating solutions and the provision of detailed drawings if required. NJMM had got the ISO9001 Quality System Certificate, CE certificate, GHOST certificate and other international certificates.
Jiulong
