I. Case Background: Municipal Sanitation Department in Shijiazhuang Procures Dongfeng D6 Blue-Plate Sewage Treatment Vehicles. In early 2025, a municipal sanitation department in Shijiazhuang (hereinafter referred to as the 'Client Unit') launched a public tender to procure a batch of blue-plate sewage treatment vehicles, aiming to address sewage sedimentation issues in aging residential communities and municipal pipelines within its jurisdiction. After multiple rounds of technical comparison and on-site inspections, the Client Unit selected Chengli Special Purpose Vehicle Co., Ltd.’s Dongfeng D6 chassis-based sewage treatment vehicles, ordering a total of 5 units with an overall budget controlled within approximately RMB 1.65 million (per publicly available tender information). The Client Unit explicitly stipulated the following requirements in its tender documents: the vehicle must feature excellent cold-start performance, enabling reliable ignition at ambient temperatures as low as -15°C; the hydraulic system must remain stable under winter low-temperature conditions to prevent oil solidification or sluggish actuation; and the entire vehicle must comply with China VI emission standards to qualify for blue-plate registration and operation within Shijiazhuang’s urban area. In response to these requirements, Chengli’s engineering team developed a customized configuration based on the MIIT-approved parameters (model CLW5070GSSD6) and leveraged the zero-inventory shipping capability of its Suizhou production base, achieving standard-vehicle delivery within 15 days. Post-delivery, the Client Unit reported: 'These vehicles performed reliably during last winter’s extreme cold snap — no difficulty starting each morning, and hydraulic arm lifting/lowering and suction operations were smoother than expected.' This real-world performance has served as a replicable procurement reference for neighboring provinces and cities (e.g., Baoding, Xingtai, and Handan). II. Cross-Regional Replication: How Adjacent Provinces and Cities Can Adopt the Shijiazhuang Experience. Following the success of the Shijiazhuang project, municipal authorities in adjacent regions—including the Urban Management Bureau of a district in Baoding City and the environmental maintenance unit of a subdistrict in Xingtai City—proactively contacted Chengli Sales Manager Zhang Yue (phone: ) to inquire about the solution. These regions face similar challenges: winter temperatures ranging from -10°C to -20°C, aging pipeline infrastructure, and shared regulatory constraints regarding blue-plate vehicle access in urban areas. Building upon the Shijiazhuang case, Chengli’s team distilled a 'Standardized Solution' for client reference: • Chassis Selection: Dongfeng D6 chassis equipped with either Quanchai or Yunnan Internal Combustion Engine, featuring standard pre-heating devices to ensure single-attempt engine start at -20°C; • Hydraulic System: Use of low-temperature hydraulic oil (pour point: -35°C), supplemented with hydraulic oil heaters to prevent low-temperature oil line blockages; • Superstructure Configuration: Suction pump selected for wear resistance and freeze protection; tank fabricated from 4 mm-thick Q235 carbon steel with internal anti-corrosion coating; • Winter Maintenance Support: Includes antifreeze coolant and low-temperature engine oil supplied with each vehicle, plus on-site training by Chengli engineers covering winter operational procedures (e.g., daily pre-heating, hydraulic system inspection). After conducting on-site inspections of the operational vehicles in Shijiazhuang, the Client Units placed orders in May and June 2025: Baoding City ordered 4 units and Xingtai City ordered 3 units—all with identical configurations and unit prices of approximately RMB 180,000 (per local procurement practice). Post-delivery feedback confirmed: 'Freeze-protection performance is indeed reliable — the vehicle started instantly on a -18°C morning last