Case Study on Dongguan's Government Procurement of Dongfeng Single-Cab Sewage Suction Truck (Blue License Plate, 5 m³): High-Load Field Performance Analysis under Humid and Hot Conditions. Located in the Pearl River Delta coastal region, Dongguan experiences scorching summers with frequent rainfall and relative humidity often exceeding 80%. Urban flooding occurs regularly during the rainy season, requiring sewage suction trucks to operate continuously under high-load, humid, and hot conditions. In 2025, a municipal sanitation department (hereinafter referred to as 'Dongguan Sanitation') publicly tendered for a batch of Dongfeng single-cab sewage suction trucks (blue license plate, 5 m³) to support routine maintenance of urban rainwater and sewage pipelines, as well as emergency flood control operations. After multiple rounds of technical and commercial evaluation, Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as 'Chengli') was selected as the supplier. This article provides an in-depth analysis—based on actual operational data and from the perspective of the fleet management director—of product performance, procurement decision-making, and management outcomes in this case. I. Fleet Management Director’s Evaluation: Process Experience from Tendering to Delivery According to Mr. Chen, Fleet Management Director of Dongguan Sanitation, the core requirements for this procurement were 'high reliability, ease of maintenance, and adaptability to southern China’s humid and hot climate.' During preliminary site inspections, Chengli’s Dongfeng single-cab sewage suction truck (blue license plate, 5 m³)—built on the Dongfeng EQ1045SJ3CDF chassis (official model number: CLW5040TQYD6)—demonstrated three key advantages: 1. Anti-Corrosion Coating Technology: To address Dongguan’s high-temperature, high-humidity environment, Chengli applied a dual-layer anti-corrosion coating system—epoxy resin primer plus polyurethane topcoat—to the tank body and critical structural components. Salt-spray testing confirmed that corrosion resistance life is approximately twice that of conventional paint systems. Mr. Chen noted: 'In other Guangdong projects, we previously encountered tank corrosion issues; Chengli’s coating solution directly resolved this pain point.' 2. Seal Durability: Sewage suction trucks frequently contact wastewater and silt during operation, causing rapid aging of seals. Chengli selected fluororubber O-rings—resistant to oil and acidic/alkaline substances—and added dust shields to enhance protection. Mr. Chen stated: 'Prior to delivery, we required a 1,000-hour continuous operation test; no leakage occurred in any seal—a rare achievement among comparable products.' 3. Complete Regulatory Compliance & Registration Convenience: The vehicle complies with China VI emission standards and qualifies as a blue-license-plate vehicle operable with a Class C driver’s license, eliminating the need for a separate road transport permit. Chengli provided full official documentation—including complete MIIT announcement parameters (model number CLW5040TQYD6)—ensuring smooth registration at the Dongguan Vehicle Administration Office. Ultimately, Dongguan Sanitation procured five units of this model at an approximate unit price of RMB 110,000 (per publicly disclosed tender information), keeping total expenditure within RMB 627,000. Chengli fulfilled the order and delivered all vehicles within just 12 days—meeting its contractual commitment of 'standard-model delivery within 7–15 days.' II. Dispatch Flexibility: Advantages of Blue-License-Plate Classification with Class C Driving License Dongguan Sanitation’s operational zones cover narrow urban streets and older residential communities where traditional yellow-license-plate sewage suction trucks (over 6 meters in length) cannot maneuver effectively. The newly procured blue-license-plate 5 m³ sewage suction truck features compact overall dimensions—no more than 5,995 × 2,000 × 2,35