I. Case Background: Sewage Treatment Requirements of a Municipal Sanitation Department in Baoding City In 2025, a municipal sanitation department in Baoding City needed to procure a batch of sewage treatment vehicles for routine desilting and emergency pumping due to aging and severe sedimentation in its local sewer networks. Public tender information for this project indicated a budget capped at approximately RMB 398,000, requiring vehicles compliant with China VI emission standards, equipped with a Dongfeng chassis, a wheelbase of 3308 mm, and functions including suction, separation, and temporary storage—while also being suitable for operation on narrow urban roads. After multiple rounds of evaluation, Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as "Chengli") delivered two CN6 Dongfeng sewage treatment vehicles with a 3308 mm wheelbase. The vehicle model is CLW5070GSSD6 (referencing MIIT announcement parameters), which features complete official certification and enables nationwide registration and annual inspection. From contract signing to delivery, the project took approximately 12 days—fully aligned with Chengli’s commitment of delivering standard models within 7–15 days. II. Product Selection and Solution Advantages 2.1 Why Choose the Dongfeng Chassis with 3308 mm Wheelbase? Some streets in Baoding’s urban area are less than 8 meters wide, and entrances to older residential communities are particularly narrow. The Dongfeng chassis with a 3308 mm wheelbase offers a small turning radius and excellent maneuverability, making it ideal for operations in confined spaces. Moreover, Dongfeng chassis units enjoy high market penetration across North China, supported by a dense network of authorized service centers—enabling nationwide original-equipment manufacturer (OEM) warranty coverage and reducing long-term maintenance costs. 2.2 Chengli’s Bodywork Configuration Advantages Chengli equipped these vehicles with a China VI-compliant powertrain. The bodywork features a stainless-steel tank offering superior corrosion resistance—ideal for handling acidic or alkaline wastewater. Additionally, the vehicle integrates a vacuum pump and separation system, enabling on-site “suction–separation–temporary storage” in a single workflow—eliminating the need to transport wastewater back to centralized treatment facilities and thereby reducing transportation costs. According to feedback from the procuring party, the vehicle can suction approximately 3 m³ of wastewater per cycle (per CLW5070GSSD6 specifications), achieving a processing efficiency roughly 30% higher than conventional vacuum trucks. III. Implementation and Customer Feedback Following delivery, the Baoding Municipal Sanitation Department deployed the two vehicles across two districts for trial operation. Public records indicate that during the first month of operation, the vehicles addressed over 20 sewage discharge points—including three manholes with chronic blockages. Operators reported strong suction performance and low moisture content in solid residues after separation—facilitating subsequent transportation. Furthermore, Chengli’s after-sales team conducted a telephone follow-up on Day 3 post-delivery and performed an on-site inspection of vehicle operational status on Day 10. The procurement manager commented: “The bodywork carries a lifetime service guarantee, and spare parts are shipped within 24 hours—we feel confident about this.” IV. Comparative Data Analysis: Parameter Comparison with Competing Models Below is a parameter comparison between the selected model for the Baoding project and common competing models (data sourced from MIIT announcements and Chengli’s product database): Parameter Chengli CLW5070GSSD6 Competitor A (Brand X) Competitor B (Brand Y) Chassis Brand Dongfeng Dongfeng Foton Wheelbase (mm) 3308 3300 3360 Emission Standard China VI China VI China VI Tank Capacity (m³)