Government Procurement Case and Bid-Winning Solution Analysis of the CN6 Dongfeng 3308-mm Wheelbase Sewage Treatment Vehicle in Tianjin In the low-temperature winter environment of North China, anti-freezing start-up performance, low-temperature hydraulic system stability, and winter maintenance plans are the core technical criteria most closely scrutinized by procuring entities. A municipal sanitation department in a district of Tianjin recently completed the procurement of a batch of CN6 Dongfeng 3308-mm wheelbase sewage treatment vehicles. Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as 'Chengli') participated in the delivery with its multi-category supply capability and one-stop service solution. This article analyzes the vehicle selection logic, technical adaptation, and procurement experience of this case based on publicly available tender information. Project Background and Core Requirements According to publicly released tender information, the municipal sanitation department of a district in Tianjin planned to procure a batch of sewage treatment vehicles to enhance winter sewage treatment efficiency, with a budget cap of approximately RMB 515,000. The tender required vehicles to comply with China VI emission standards; chassis must be Dongfeng 3308-mm wheelbase (i.e., Dongfeng Duolika series); and the superstructure must feature anti-freezing start-up capability, low-temperature hydraulic system stability, and an accompanying winter maintenance plan. Having previously deployed other Chengli sanitation vehicles—such as water-sprinkling trucks and vacuum suction trucks—the department selected Chengli as a preferred supplier based on prior trust. Chengli’s proposed solution drew upon the technical foundations of CLW5070GSSD6 (water-sprinkling truck) and CLW5180GSSD6 (water-sprinkling truck) models listed in the Ministry of Industry and Information Technology (MIIT) announcements, customizing modifications specifically for sewage treatment applications. The core configuration features a Dongfeng 3308-mm wheelbase chassis integrated with Chengli’s proprietary superstructure system—including stainless-steel tank body, hydraulic pump, and intelligent control system. Technical Solution: Anti-Freezing Start-Up and Low-Temperature Hydraulic Stability Tianjin’s winter temperatures frequently drop below –10°C, imposing stringent requirements on vehicle start-up performance and hydraulic systems. Chengli implemented the following measures in this solution: Anti-Freezing Start-Up System: Installation of low-temperature start-up assist devices—including glow plugs and electrically heated oil pans—to ensure reliable ignition even at –20°C. These devices conform to Dongfeng chassis nationwide warranty standards and have passed laboratory testing for compliance with China VI emission requirements. Low-Temperature Hydraulic Stability: Use of low-temperature hydraulic oil (viscosity index >150), coupled with upgraded thermal insulation layers on hydraulic piping to minimize resistance during cold starts. Under Chengli’s lifetime superstructure service program, these components are covered by a 24-hour direct-parts-delivery guarantee. Winter Maintenance Plan: Provision of scheduled replacement plans for antifreeze coolant, engine oil, and filters, with comprehensive inspections conducted every 500 operating hours or quarterly to ensure stable operation under extreme weather conditions. This solution directly addresses the procuring entity’s primary concern—'low-temperature operational reliability'—effectively avoiding common winter issues such as difficult starting or hydraulic system failures experienced with conventional vehicles. Multi-Category Supply Capability: One-Stop Procurement Reduces Management Costs Beyond sewage treatment vehicles, this project also involved concurrent procurement of other sanitation vehicles—including water-sprinkling trucks and vacuum suction trucks. As one of China’s large