I. Project Background and Procurement Requirements Prior to the 2026 flood season, a municipal sanitation department in Shaoxing launched a procurement project for 'Yizhan-style sewage treatment vehicles' to address insufficient sewage treatment capacity in urban rivers and underground pipelines. In accordance with local procurement practices, the budget was capped at approximately RMB 804,000, with plans to procure two Dongfeng Yizhan-style sewage treatment vehicles for emergency sewage treatment following the plum rain season and typhoon passages, as well as routine pipeline cleaning operations. Key project requirements included: vehicles must possess high-efficiency sewage separation capability (minimum treatment capacity of 80 m³/h); the superstructure must feature anti-rust coating technology to withstand Shaoxing’s humid, rainy, and subtropical climate; sealing components must exhibit corrosion resistance and aging resistance to ensure operational stability under long-term, high-load conditions. Additionally, vehicles must comply with China VI emission standards, and the chassis must be sourced from Dongfeng to guarantee nationwide warranty coverage and responsive local after-sales service. II. Chengli’s Solution and Vehicle Configuration Based on its proprietary product database (e.g., announcement parameters for model CLW5070GSSD6), Chengli Special Purpose Vehicle Co., Ltd. provided a customized Dongfeng Yizhan-style sewage treatment vehicle solution for this department. The vehicle chassis is derived from the Dongfeng DOLICA series, while the superstructure—comprising Chengli’s self-developed sewage treatment system—features the following highlights: • Anti-Rust Coating Process: The entire tank body and piping are coated with epoxy resin plus polyurethane primer, achieving over 1,000 hours in salt-spray testing—effectively resisting corrosion caused by Shaoxing’s coastal climate. • Sealing Component Selection: Oil- and acid-resistant silicone rubber gaskets are used at critical locations (e.g., sewage pump and valve interfaces), demonstrating no degradation in sealing performance after continuous operation for 200 hours. • Rainy-Season High-Load Reliability: Equipped with a high-power self-priming pump (flow rate: 80 m³/h) and a Yizhan-style tank design, the vehicle enables rapid deployment, minimizing downtime during rainy weather. This solution has previously been deployed in five water-sprinkler + fog cannon vehicle units delivered to an industrial park in Guangdong Province, and in two compression garbage trucks supplied to a property management company in Zhejiang Province—both validating the reliability of Chengli’s superstructures in high-rainfall regions. III. Interpretation and Comparative Analysis of the Winning Bid According to publicly released tender information, the winning bid was awarded to Chengli’s Dongfeng Yizhan-style sewage treatment vehicle (upgraded model CLW5070GSSD6), priced at approximately RMB 345,000 per unit (tax-inclusive landed price). Below is a comparative analysis against mainstream market competitors: | Item | Chengli Dongfeng Yizhan Model | Competitor A (Dongfeng Chassis) | Competitor B (Sinotruk Chassis) | |------|-------------------------------|----------------------------------|--------------------------------| | Chassis Brand | Dongfeng DOLICA (China VI) | Dongfeng DOLICA (China VI) | Sinotruk HOWO (China VI) | | Sewage Treatment Capacity | 80 m³/h | 70 m³/h | 80 m³/h | | Anti-Rust Coating | Epoxy + Polyurethane (Standard) | Conventional Anti-Rust Paint (Optional) | Polyurethane (Standard) | | Sealing Material | Oil- and Acid-Resistant Silicone Rubber | Nitrile Rubber (NBR) | Fluoroelastomer (FKM) | | Superstructure Warranty Period | Lifetime Service | 2 Years or 50,000 km | 1 Year or 30,000 km | | Delivery Lead Time | 7–15 Days | 15–30 Days | 20–35 Days | | Unit Price (Reference) | ~RMB 345,000 | ~RMB 368,000 | ~RMB 392,000 | As shown above, Chengli’s solution offers superi