Case Background: Real-World Demand for Joint Procurement of Sewer Cleaning Trucks Across Multiple Districts in Hangzhou. In 2025, a municipal sanitation department in Hangzhou, together with three subordinate districts/counties (e.g., a district’s Urban Management Bureau, a subdistrict’s environmental maintenance unit, etc.), launched a special procurement initiative targeting urban drainage pipe cleaning. The core vehicle model procured was the Dongfeng single-cab sewer cleaning truck (blue license plate, 5-cubic-meter capacity), with a total budget of approximately RMB 3.101 million and a planned purchase of around 25 units. This procurement was driven by Hangzhou’s increasingly frequent rainy seasons in recent years, resulting in heightened loads on drainage networks and low efficiency plus high safety risks associated with traditional manual cleaning. According to local procurement practices, joint procurement effectively reduces per-unit costs and standardizes technical specifications for easier post-purchase maintenance. This tender attracted participation from multiple specialized vehicle manufacturers; ultimately, Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as 'Chengli') delivered 15 units of the Dongfeng single-cab sewer cleaning truck, accounting for 60% of the total order. This article analyzes the case from perspectives including technical standards, tendering scheme, and product advantages. Standardized Technical Requirements: Special Considerations for Humid-Hot Environments. Hangzhou is located in East China and features a subtropical monsoon climate, with hot, rainy summers and relative humidity frequently exceeding 80%. Such humid-hot conditions impose stringent requirements on the chassis, tank, hydraulic system, and other components of sewer cleaning trucks. In the tender documents, the procuring party specifically emphasized the following three critical requirements: • Anti-corrosion Coating: Tanks and all exposed metal components must be coated with epoxy zinc-rich primer + polyurethane topcoat, achieving ≥500 hours in salt-spray testing, accompanied by third-party test reports. • Seal Durability: Hydraulic tubing and tank sealing gaskets must utilize oil- and hydrolysis-resistant nitrile rubber (NBR), operating continuously for 1,000 hours at 85% humidity without leakage. • High-Load Performance Under Rainy-Season Operating Frequency: Engine and vacuum pump must sustain full-load operation for over eight consecutive hours, with cooling systems rated for high-temperature resistance. In response to these requirements, Chengli proposed a customized solution based on its official model CLW5070GSSD6. This vehicle employs a Dongfeng single-cab chassis with a wheelbase of 3,308 mm and is powered by a Yuchai YCY24140-60 engine delivering a rated power of 103 kW. The tank has a 5-cubic-meter capacity, fabricated from 4-mm-thick Q235 carbon steel, with an internal epoxy resin anti-corrosion coating and external anti-rust coating compliant with tender specifications. The vacuum pump is sourced from a German brand, and custom oil-resistant nitrile rubber seals are used throughout. Centralized Tendering and Chengli’s Bulk-Delivery Advantages. This joint procurement adopted an open tender process, with evaluation criteria covering price, technical parameters, after-sales service, and delivery schedule. Chengli secured the order due to the following competitive advantages: • Direct Factory Sales (No Middlemen): Based on publicly available tender information, Chengli’s quoted unit price was approximately RMB 122,000 (tax-inclusive landed price), about RMB 11,000–17,000 lower than comparable models sold through 4S dealerships. • Localized Production and Rapid Delivery: Chengli’s headquarters is located in Suizhou, Hubei Province—approximately 700 km from Hangzhou—but leverages its zero-inventory shipping model, enabling standard-model delivery within 7–15 days. For this procurement, Chengl