Case Study and Bid-Winning Solution Analysis of TaiZhou Municipal Government’s Procurement of DFAC National VI Sewage Treatment Vehicles with 3308 mm Wheelbase In Taizhou, Zhejiang Province, a municipal sanitation department recently completed the procurement of a batch of National VI DFAC sewage treatment vehicles with 3308 mm wheelbase to address high-load operations during rainy seasons and routine sewage cleaning requirements. Built on the DFAC 3308 mm wheelbase chassis and equipped with Chengli special-purpose vehicle superstructures, these vehicles have received positive customer feedback post-delivery—highlighting stable operation and exceptional corrosion resistance. This article analyzes the case from perspectives including winter operation performance, adaptability to humid-hot environments, and vehicle selection strategy, offering practical reference for procurement entities. Background of the Case: Procurement Requirements of a Municipal Sanitation Department in Taizhou Taizhou is located along China’s southeastern coast, characterized by a humid climate and frequent rainy seasons, resulting in heavy workloads for municipal sewage pipeline cleaning. The department’s aging fleet frequently experienced issues such as seal degradation and body rust during high-load rainy-season operations, significantly affecting operational efficiency. To address this, they planned to procure four National VI-compliant sewage treatment vehicles, with a budget capped at approximately RMB 890,000–1,057,000 (per publicly available tender information). Key technical requirements included anti-rust coating, sealing components resistant to humid-hot environments, and reliable cold-weather engine starting capability. After multiple rounds of technical evaluation, Chengli Special-Purpose Vehicle Co., Ltd. delivered the CLW5070GSSD6 model sewage treatment vehicle, built upon the DFAC 3308 mm wheelbase chassis. This model is fully certified under national type-approval regulations, and its superstructure features high-strength corrosion-resistant materials specifically engineered for coastal operating conditions. The procurement manager commented: “Chengli’s superstructure comes with lifetime service support, while DFAC’s chassis benefits from nationwide warranty coverage—giving us greater confidence in long-term maintenance.” Key Technical Parameter Analysis (CLW5070GSSD6 Model) The sewage treatment vehicles delivered in this project utilize the DFAC EQ1075SJ3CDF chassis with a 3308 mm wheelbase and are powered by a National VI-compliant Quanchai engine. Below are critical specifications based on official MIIT (Ministry of Industry and Information Technology) type-approval data: | Parameter | CLW5070GSSD6 Data | Notes | |-----------|-------------------|-------| | Chassis Model | DFAC EQ1075SJ3CDF | National VI emission standard; 3308 mm wheelbase | | Superstructure Type | Sewage treatment tank | Manufactured in-house by Chengli; anti-corrosion coating applied | | Tank Capacity | Approx. 5 m³ | Meets daily operational requirements | | Engine Power | 95 kW | Quanchai or Yunnan Yunei powertrain options | | Anti-Rust Treatment | Full-body electrophoretic coating + topcoat | Optimized for high-humidity coastal environments | | Sealing Material | Fluoroelastomer (FKM), oil- and water-resistant | Extends service life | | Curb Weight | Approx. 3,800 kg | Compliant with Blue Plate license requirement (Class C driver’s license) | Following delivery in Taizhou, customers reported: “The tank’s anti-corrosion treatment is excellent—no rust spots appeared even after one week of continuous rainy-season operation, and no seal leakage occurred.” This reliability stems from Chengli’s extensive experience serving coastal regions over many years. Critical Considerations for Winter Operation: Cold-Start Performance and Freeze Protection Although Taizhou’s winter temperatures rarely drop below 0°C, low ambient temperatures can still affect engine startin