Explore our premier line of certified structural solutions manufactured to rigorous global standards.
Pioneering Heavy-Duty Structural Grating and Industrial Safety Infrastructure Since 1993
Ningbo Jiulong Machinery Manufacturing Co., Ltd (NJMM) was founded in 1993, engaging primarily in the design and manufacturing of steel grating, structural railings, heavy-duty platforms, and light steel frameworks. As a modern comprehensive enterprise seamlessly integrating scientific research, precise machinery manufacturing, and complex engineering construction, NJMM stands at the pinnacle of industrial grating innovation.
We currently operate two massive production bases located strategically in the East and North of China, featuring 12 state-of-the-art steel grating automated pressure-welding production lines. Our technical ecosystem is fully supported by advanced auxiliary processing equipment and testing facilities, including robotic welding systems, high-precision fiber laser cutting, and digital control panel tailoring instruments. Our annual output across structural steel gratings, trench covers, stair treads, stanchions, handrails, and security fences exceeds 50,000 metric tons.
m² Workshop Core Area (Over 45,000m² Total Facility)
Automated Grating Pressure-Welding Production Lines
Metric Tons Annual Comprehensive Output Capacity
Global International Service Networks & Regions
Deep Dive into Global Market Dynamics, Technical Routes, and Future Engineering Horizons
Serrated carbon steel bar grating remains an indispensable structural asset in high-moisture, heavy-oil, and extreme-weather industrial sectors worldwide. From offshore drilling rigs in the North Sea to sprawling petrochemical complexes in the Middle East and mining operations in South America, anti-slip grating infrastructure prevents catastrophic slip-and-fall hazards while ensuring uncompromised load-bearing capability under extreme dynamic loads.
Manufactured via high-amperage resistance pressure welding or forge-welding techniques, carbon steel bearing bars are permanently fused with cross rods. Subsequent serration machining applies deep, teeth-like grooves along the bearing bar top edge, boosting friction coefficients significantly. Post-fabrication hot-dip galvanizing (complying with ASTM A123 / ISO 1461 standards) encapsulates the serrations in a robust zinc-iron alloy layer, ensuring a 30+ year maintenance-free lifecycle.
The future of steel grating engineering leans toward digital design integration (BIM-ready parameters), automated robotic fabrication, and low-carbon metallurgical inputs. As a recognized green factory and municipal engineering center, NJMM continuously optimizes material efficiency, reducing dead loads without sacrificing structural integrity, aligning perfectly with global net-zero industrial construction mandates.
Unrivaled Expertise, Certified Quality Management, and Comprehensive Engineering Support
NJMM markets its products globally to South America, Europe, Oceania, Africa, West Asia, Southeast Asia, and the Middle East. Domestically, our 'Longta' branded gratings are specified in premier national infrastructure projects, backed by rapid supply chain execution.
Equipped with 12 automatic pressure welding lines, 6 automated banding robots, and specialized irregular grating fabrication platforms, our capacity exceeds 50,000 tons annually, with over 20,000 tons dedicated to international exports.
NJMM holds ISO9001:2015, ISO45001:2018, ISO14001:2015, and CE certifications. We actively participated in drafting and revising the Chinese national steel grating standard YB/T4001, cementing our authoritative industry standing.
Engineered for Versatility Across Diverse Heavy Industries and Municipal Engineering
Widely implemented in refineries, chemical processing units, and offshore platforms. Recommended configurations like JG255/30/100 and JG325/30/100 offer superior ventilation, light transmission, heat dissipation, and explosion-proof anti-skid performance.
Utilized in shipbuilding, port docks, and heavy mining infrastructure. High-load variants such as G505/30/100 and JG705/30/100 withstand intense vehicular traffic while preventing debris accumulation through precise grid spacing.
Deployed in water treatment plants, power generation stations, stair steps, and architectural ceilings. Serrated profiles guarantee exceptional slip resistance in wet or icy environments without impeding drainage.
Expert Answers to Critical Engineering and Sourcing Inquiries Regarding Serrated Carbon Steel Bar Gratings
Serrated carbon steel bar gratings feature mechanical teeth or notches cut into the top edge of the bearing bars. This serration significantly increases the friction coefficient, providing exceptional anti-slip safety (meeting or exceeding R12/R13 slip-resistance ratings) for workers walking on platforms exposed to rain, oil, grease, or chemical slurries.
After fabrication and serration, the grating panels are immersed in molten zinc at approximately 450°C. This metallurgical reaction forms a robust series of zinc-iron alloy layers bonded tightly to the carbon steel base, providing both barrier protection and sacrificial cathodic protection that prevents rust for decades, even in marine or highly corrosive industrial atmospheres.
NJMM offers full engineering support, including custom load calculations, specialized panel cutouts for pipes and machinery, detailed CAD shop drawings, and tailored installation guidelines. Our dual production facilities and automated robotic cutting ensure precise adherence to project specifications worldwide.
Standard bearing bar depths typically range from 25mm to 100mm with thicknesses of 3mm to 6mm. Common center-to-center spacings are 30mm or 40mm for bearing bars, and 50mm or 100mm for cross rods. Custom pitch configurations are readily manufactured upon request to match specific architectural or structural loading requirements.
Comprehensive catalog of forge-welded, plain, serrated, and specialized architectural gratings.
Jiulong