Chengdu Dongfeng Single-Cab Sewer Cleaning Truck (Blue License Plate, 5 m³) – Government Procurement Case: Field Inspection and Vehicle Selection Analysis. I. Project Background and Leadership Requirements. In early 2025, an environmental maintenance unit of a subdistrict in Chengdu faced severe sedimentation in the drainage pipelines of aging residential communities within its jurisdiction, resulting in frequent drainage failures during the rainy season. During an internal meeting, the department head explicitly stated: 'We must procure a batch of sewer cleaning trucks; however, the budget is limited. Vehicles must comply with blue license plate regulations and be operable with a Class C driver’s license, while also being suitable for Chengdu’s hot, humid summers and high-frequency rainy-season operations.' Previously, the unit relied primarily on manual cleaning—low-efficiency and posing safety hazards. The leadership emphasized: 'Vehicles must withstand high-load operation, especially regarding rust prevention and seal durability—equipment must not suffer frequent failures due to the hot-humid environment.' Per local procurement practice, the total budget was capped at approximately RMB 277,000, with an estimated unit price of around RMB X0,000 (based on publicly available tender information). II. Internal Discussions and Selection Criteria. Upon receiving the assignment, the Procurement Section and Equipment Section jointly conducted multiple rounds of internal discussions, focusing on the following four key criteria: Chassis Selection: Dongfeng single-cab chassis was prioritized due to its large market presence and extensive service network across Southwest China. It must comply with blue license plate requirements (Class C license), have an overall length ≤6 meters, and a gross vehicle weight rating (GVWR) ≤4.5 tons. Tank Material and Corrosion Resistance: Given Chengdu’s humid climate and prolonged rainy season, the tank interior must feature anti-corrosion coating to prevent perforation from long-term exposure to sewage. Seal Durability: As sewer cleaning trucks frequently operate in damp, acidic/alkaline wastewater environments, hydraulic cylinder seals and tank gasket strips must resist corrosion and aging. Regulatory Compliance and Registration: The vehicle must meet China VI emission standards, possess complete official announcements (type-approval), and support nationwide registration and annual inspections. After comparative evaluation of multiple brands on the market, the Dongfeng single-cab sewer cleaning truck manufactured by Chengli Special Purpose Vehicle Co., Ltd. (model reference: CLW5070GSSD6 series) entered the shortlist. This model features a 5 m³ tank capacity, utilizes a Dongfeng single-cab chassis compliant with blue license plate regulations, and benefits from Chengli’s extensive experience serving over 500 municipal sanitation units nationwide. III. On-Site Factory Inspection at Chengli. To verify actual vehicle performance, the department head led a four-member delegation—including representatives from the Equipment Section and Finance Section—to conduct an on-site inspection at Chengli Automobile Industrial Park, located at No. 1 Chengli Avenue, Economic Development Zone, Suizhou City, Hubei Province. Key inspection activities included: Production Workshop: Observation of tank welding techniques and anti-corrosion coating application processes. Chengli technical staff explained that the tank is fabricated from high-strength steel plates, subjected to acid pickling and phosphating, then coated with epoxy resin anti-rust primer and topcoat; additionally, an inner corrosion-resistant coating is applied to ensure reliable high-load operation under hot-humid conditions. Seal Performance Testing: Hydraulic cylinder seals and tank gasket strips were tested under simulated high-humidity conditions. Chengli samples underwent 1,000 consecutive opening/closing cycles without leakage—gaining approval from th