Government Procurement Case of New Dongfeng Sewage Treatment Vehicle in Shenzhen: Analysis of High Anti-Corrosion and Humid-Tropical Environmental Adaptability Solutions As a coastal city, Shenzhen’s high-temperature, high-humidity, and rainy climate imposes stringent requirements on sanitation special-purpose vehicles. Recently, a municipal sanitation department procured a batch of new Dongfeng sewage treatment vehicles via public tender for emergency treatment of urban drainage networks and river sewage. Chengli Special Purpose Automobile Co., Ltd. successfully delivered the vehicles, leveraging its deep expertise in humid-tropical environmental adaptability design. This article analyzes the project background, reasons for winning the bid, technical highlights, and reference cases for similar projects based on publicly available tender information. I. Project Basic Information According to publicly released tender information, this procurement involves new Dongfeng sewage treatment vehicles, with a total budget capped at approximately RMB 2.255 million, covering four units. Vehicles must comply with China VI emission standards and demonstrate long-term stable operation capability under Shenzhen’s humid-tropical climate conditions. The procuring entity explicitly stipulated in the tender documents: anti-corrosion coating grade must meet or exceed C4 level; critical sealing components (e.g., tank interfaces, pumps and valves) must pass durability testing under humid-tropical conditions; and vehicles must support high-frequency operation (minimum daily operational duration of no less than 8 hours during rainy season). Chengli Special Purpose Automobile secured the bid at an approximate unit price of RMB 450,000, resulting in a total contract value of approximately RMB 2.029 million. Since delivery, these vehicles have been deployed across multiple municipal drainage projects in Shenzhen, with customer feedback confirming stable performance under high-load rainy-season operating conditions. II. Analysis of Reasons for Chengli’s Bid Success Chengli Special Purpose Automobile won this project primarily due to the following three advantages: 1. Leading Anti-Corrosion Coating Technology: To address Shenzhen’s coastal high-salt-fog environment, Chengli applied full hot-dip galvanizing to both chassis and tank body, followed by application of epoxy zinc-rich primer and polyurethane topcoat, achieving a total coating thickness exceeding 200 μm—significantly surpassing industry standards. Reference is made to the CLW5180GSSD6 model listed in the Ministry of Industry and Information Technology (MIIT) announcement; its Dongfeng OEM chassis has undergone multiple rounds of verification for corrosion resistance in southern China. 2. Optimized Weather-Resistant Sealing Components: Chengli specially selected fluororubber O-rings for the sewage treatment vehicle—exhibiting excellent resistance to high temperature and ozone—and maintaining elasticity even at 80% relative humidity, ensuring leak-free connections between tank and piping. During on-site testing by the procuring entity, these seals showed no deformation after continuous 72-hour operation under high-humidity conditions. 3. High-Load Operational Reliability: The vehicle features a high-capacity sewage pump (60 m³/h) equipped with an automatic backflushing system, effectively preventing sludge blockage during frequent rainy-season operations and minimizing downtime for maintenance. Chengli also committed to lifelong upper-body assembly service and guaranteed 24-hour direct shipment of spare parts—addressing municipal authorities’ concerns regarding after-sales responsiveness. III. Vehicle Technical Highlights: Adaptability Design Based on Dongfeng Chassis The newly delivered Dongfeng sewage treatment vehicles are built upon the Dongfeng Dorica chassis, with the upper-body assembly designed and manufactured by Chengli Special Purpose Automobile. Key technical highlights include: