Government procurement case of CN6 Dongfeng 3308 mm wheelbase sewage treatment vehicle in Fuzhou: In-depth analysis of Chengli's solution. I. Project Background: High-Load Operation Requirements in a Humid and Hot Environment. In Q2 2025, the municipal sanitation department of a district in Fuzhou City issued a procurement plan for sewage treatment vehicles. The project site is located downstream of the Minjiang River, where the annual average humidity exceeds 80%, rainfall is highly concentrated during the rainy season, and operational frequency is high. The client urgently required a batch of sewage treatment vehicles capable of stable operation under high-humidity, high-salt-fog, and high-load conditions to support urban pipeline maintenance, emergency pumping and drainage, and auxiliary river dredging operations. After preliminary research and parameter screening, the procuring entity ultimately selected the CN6-emission-standard Dongfeng 3308 mm wheelbase chassis, requiring the superstructure to deliver high-efficiency suction, solid-liquid separation, and rapid discharge capabilities. Regarding budget control, consistent with local procurement practices, the unit vehicle budget was set between RMB 309,000 and RMB 350,000, with a total requirement of four units. The project attracted bids from multiple leading sanitation vehicle manufacturers, including Chengli Special Purpose Vehicle Co., Ltd. II. Key Bidding Brands and Comparative Analysis of Strengths and Weaknesses. A total of four professional sanitation vehicle manufacturers participated in this tender: Chengli Special Purpose Vehicle, Zoomlion Environmental Industry, a local Fujian-based upfitting plant (hereinafter referred to as "Factory A"), and a technology company specializing in sewage treatment equipment (hereinafter referred to as "Company B"). Their proposals were evaluated across four key dimensions: corrosion resistance, sealing component durability, performance under rainy-season high-load conditions, and after-sales service. Comparison Dimension | Chengli Special Purpose Vehicle | Zoomlion Environmental Industry | Factory A (Local Fujian Upfitting Plant) | Company B (Technology Company) ---|---|---|---|--- Chassis Configuration | Dongfeng 3308 mm wheelbase, CN6 emission standard, OEM chassis, nationwide warranty | Dongfeng or Sinotruk chassis options available; complete official announcements | Dongfeng chassis used, but not the standard 3308 mm wheelbase model—customization required | No dedicated chassis announcement; requires external procurement and secondary modification Corrosion Protection Coating | Full-vehicle electrophoretic coating + epoxy primer + polyurethane topcoat; reinforced anti-corrosion treatment applied to tank and piping; passed 1,000-hour salt spray test | Standard electrophoretic coating; galvanized steel used for parts of tank | Conventional anti-rust paint only; no special coating | Stainless-steel tank material used, but entails higher cost and weight Sealing Component Durability (Humid-Hot Environment) | Imported fluororubber seals with excellent temperature resistance, oil resistance, and weather resistance—optimized for Fuzhou’s high-humidity environment | Domestic nitrile rubber seals; moderate durability | Conventional rubber seals prone to aging in humid-hot environments | Custom-designed seals, yet lacking real-world operational validation Rainy-Season High-Load Performance | Equipped with high-capacity vacuum pump + reinforced separation system; maintains full performance over 8-hour continuous operation; mature automatic drainage system | Stable pump performance, but separation efficiency slightly reduced during rainy-season slurry operations | Insufficient power matching; prone to overheating and shutdown during rainy-season operations | High equipment integration level, but poor compatibility between chassis and superstructure After-Sales Service | Nationwide Dongfeng chassis warranty; lifetime superstructure servi