In Liuzhou—a southern Chinese city characterized by frequent rainfall and high humidity—municipal sanitation departments have long faced unique challenges in procuring sewage treatment vehicles. In 2025, a municipal sanitation department planned to procure a batch of new Dongfeng sewage treatment vehicles for urban sewer network cleaning and emergency response. After multiple rounds of tendering and solution evaluation, Chengli Special Purpose Vehicle Co., Ltd. successfully delivered four units based on Dongfeng chassis and equipped with high-efficiency sewage systems. This article analyzes the winning procurement solution through a comparative assessment of Chengli’s model versus another mainstream market brand across ten key dimensions, revealing the underlying technical rationale and cost-control strategy. Procurement Background and Requirements Analysis The procuring entity is a municipal sanitation department responsible for urban drainage network maintenance, emergency flood control during the rainy season, and sewage transfer. Liuzhou features a subtropical monsoon climate, with an average annual rainfall of approximately 1,400 mm and hot, humid summers—conditions that accelerate corrosion of vehicle chassis and tanks. Consequently, the buyer specified stringent requirements regarding anti-corrosion coating quality, sealing component durability, and high-load performance during frequent rainy-season operations. According to publicly released tender documents, the total budget was capped at approximately RMB 1.338 million for four vehicles (i.e., ~RMB 300,000 per unit). Vehicles were required to comply with China VI emission standards, feature tank capacities of no less than 8 m³, and possess self-priming/self-discharging and high-pressure cleaning capabilities. Following two rounds of screening, Chengli Special Purpose Vehicle (Model CLW5110GXWD6) and another leading brand, Lüjie Environmental Protection (Model LJ5110GXW6), advanced to final comparison. Chengli vs. Lüjie Environmental Protection: Ten-Dimensional Comparative Scoring Table The following comparative evaluation is based on publicly available tender documents, actual vehicle specifications, and user feedback. Scoring scale: 5-point system, where 5 = optimal. Scoring Dimension Chengli CLW5110GXWD6 Lüjie Environmental Protection LJ5110GXW6 Basis for Scoring 1. Anti-corrosion Coating Quality 5 3 Chengli employs a dual-layer epoxy resin + zinc-based coating, achieving >1,200 hours in salt-spray testing; Lüjie uses a single-layer acrylic coating, rated at only 800 hours. 2. Sealing Component Durability (in Humid-Hot Environments) 5 4 Chengli utilizes fluororubber seals—resistant to acids, alkalis, and high temperatures; Lüjie uses nitrile rubber, which tends to age prematurely above 70°C. 3. High-Load Performance During Rainy Season 5 4 Chengli features a standard dual-pump system delivering 120 m³/h flow rate, sustaining full performance over 8 consecutive hours; Lüjie employs a single-pump system, with efficiency dropping 15% after 4 continuous hours. 4. Chassis Integration & Powertrain 5 4 Chengli is built on the Dongfeng Dorica chassis powered by a Yuchai 140-hp engine meeting China VI standards; Lüjie uses a Foton chassis with comparatively lower power output. 5. Tank Material & Capacity 5 4 Chengli’s tank is fabricated from Q345B manganese steel (6 mm thickness, 8.5 m³ capacity); Lüjie uses Q235 carbon steel (5 mm thickness). 6. Self-Priming/Self-Discharging Efficiency 5 3 Chengli achieves an 8-meter suction lift and completes discharge within 3 minutes; Lüjie offers only a 6-meter suction lift and requires 5 minutes for discharge. 7. High-Pressure Cleaning System 5 4 Chengli is equipped with an Italian-imported high-pressure pump (280 bar); Lüjie uses a domestic pump (220 bar).