I. Background: Procurement Decision Validated Over Three Years — From Initial Order to Contract Renewal In early 2022, a municipal sanitation department (hereinafter referred to as “Unit A”) planned to procure a batch of National VI emission-compliant sewage treatment vehicles due to aging local wastewater treatment infrastructure and insufficient processing capacity. Following multiple rounds of technical evaluation and on-site inspections, Unit A selected the Dongfeng 3308 mm wheelbase sewage treatment vehicle (model CLW5070GSSD6) manufactured by Chengli Special Purpose Vehicle Co., Ltd. The initial delivery consisted of five units, each priced at approximately RMB 152,000 (estimated based on local procurement practices and publicly available tender information). In 2024, Unit A launched another procurement round, ordering an additional five units of the same model and two upgraded high-pressure cleaning and suction-sewer trucks (model CLW5070GSSD6 Enhanced Version). The total value of both procurements amounted to approximately RMB 1.2 million (based on publicly available tender data). According to feedback from Unit A’s procurement manager: “Over three years of operation, this vehicle has demonstrated an exceptionally low failure rate—its chassis remains highly stable, and the upper assembly has experienced virtually no downtime. When renewing the contract in 2024, we compared alternatives from other brands but ultimately chose Chengli again—because long-term users know that time saved on maintenance translates directly into real cost savings.” This case exemplifies the typical government procurement decision pathway: “initial trial → operational validation → contract renewal and scale-up.” II. Vehicle Overview: Technical Specifications and Configuration of Model CLW5070GSSD6 The chassis used for this procurement is the Dongfeng 3308 mm wheelbase model EQ1075SJ3CDF; the upper assembly features Chengli’s proprietary sewage treatment system, with the official announcement model number CLW5070GSSD6. Key specifications are listed below (based on MIIT announcement data and internal company knowledge base): | Item | Parameter | Remarks | |------|-----------|---------| | Chassis Model | Dongfeng EQ1075SJ3CDF | Wheelbase: 3308 mm | | Engine | Yunnan Power D20TCIF1 (National VI) | Power: 93 kW; Torque: 350 N·m | | Tank Capacity | 3.5 m³ (sewage) | Customizable | | Vacuum Pump | Water-Circulating Type | Suction depth ≥ 6 meters | | Suction System | Hydraulic Control + Manual Operation | Maximum suction lift: 8 meters | | Discharge System | Self-Dumping + Pressure Discharge | Supports reverse flushing | | Gross Vehicle Weight | 4,490 kg | Upper assembly weight ≈ 800 kg | | Rated Payload | 2,780 kg | Compliant loading capacity | | Overall Dimensions | 5,995 × 1,980 × 2,550 mm | Blue license plate; drivable with Class C driver’s license | | Emission Standard | National VIb | Nationwide registration eligible | The core strengths of this model lie in its Dongfeng OEM chassis—backed by nationwide warranty—and Chengli’s lifetime service support for the upper assembly. During actual use, Unit A observed that the vacuum pump system maintained stable suction performance even after eight consecutive hours of operation, and the hydraulic control valve group exhibited longer service life than comparable products. According to Chengli’s after-sales records, only one set of seals and two hydraulic hoses were replaced across the entire batch over three years—both classified as routine wear items. III. Procurement Process and Bid Award Analysis In the first tender conducted in 2022, Unit A adopted an “open tender” method, with a budget cap of RMB 889,000 (for five units). Evaluation criteria were weighted as follows: Technical Score (30%) — including chassis brand, upper-assembly configuration, and completeness of official announcements; Price Score (40%); After-sales Support Score (30%).