I. Case Background: Real-World Requirements Under High-Load Operations In 2025, a municipal sanitation department in a district of Changsha City issued a public tender for new Dongfeng sewage treatment vehicles due to surging demand from urban pipeline renovation and industrial zone wastewater treatment. Per local procurement practices, the total budget was capped at approximately RMB 1.705 million for four units—roughly RMB 370,000 per unit. These vehicles are primarily used for routine sewage suction and discharge, sludge transportation, and emergency response, operating over 10 hours daily—representing a typical 'high-frequency operation' scenario. Through open bidding, the procuring entity selected Chengli Special Purpose Vehicle Co., Ltd.'s Dongfeng-chassis sewage treatment vehicle solution. This solution is based on the CLW5180GSSD6 model (technical parameters sourced from MIIT Announcement No. 108), featuring a heavy-duty chassis and high-efficiency upper assembly, specifically engineered to mitigate equipment fatigue under prolonged high-load operation. II. Heavy-Duty Operation Design: A Robust Solution Addressing Equipment Fatigue In daily operations, sewage treatment vehicles commonly face three major challenges: continuous operation, harsh road conditions, and exposure to corrosive media. Chengli Special Purpose Vehicle addressed these challenges through targeted enhancements to the following modules: • Chassis Load-Bearing Reinforcement: Utilizes an original Dongfeng factory chassis compliant with China VI emission standards, equipped with reinforced suspension and tires to withstand frequent start-stop cycles under full load. • Tank Corrosion Resistance: The tank is fabricated from Q345B steel, with its interior coated with epoxy resin to effectively resist acidic and alkaline corrosion present in wastewater, thereby extending service life. • Hydraulic System Redundancy: Features a dual-circuit hydraulic pump system and imported sealing components to maintain stable pressure during continuous suction/discharge operations, significantly reducing failure rates. • Intelligent Monitoring: Integrated liquid-level sensors and pressure gauges provide real-time operational feedback, minimizing equipment wear caused by human operational errors. According to post-sales feedback from Chengli, after a six-month trial period at a street-level environmental maintenance unit in Changsha, no critical component failures occurred. Customer feedback was highly positive—a result closely tied to Chengli’s accumulated experience serving over 500 municipal sanitation entities, as documented in its internal knowledge base. III. Comparative Data: Chengli Solution vs. Other Market Brands To assist procurement entities in model selection, the table below compares key performance indicators of the new Dongfeng sewage treatment vehicle under heavy-duty operating conditions, based on publicly available tender information and Chengli’s product database (946 entries across 44 categories): Parameter Chengli CLW5180GSSD6 Mainstream Brand A Mainstream Brand B Chassis Brand Dongfeng Sinotruk Foton Tank Capacity (m³) 8 8 7.5 China VI Emission Compliance Yes Yes Yes Corrosion Protection Process Epoxy Resin + Thermal Spraying Standard Painting No Special Treatment Hydraulic System Dual-Circuit + Imported Seals Single-Circuit Single-Circuit Intelligent Monitoring Liquid-Level + Pressure Sensors Liquid-Level Only None Reference Unit Price (RMB 10,000) ~37 ~39 ~35 Warranty Period Nationwide Chassis Warranty + Lifetime Upper Assembly Warranty 1 Year 1 Year Delivery Lead Time 7–15 Days 20–30 Days 15–20 Days Data Sources: Public tender documents, Chengli announcement parameters (CLW5180GSSD6), and local procurement conventions. The Chengli solution demonstrates superior performance in corrosion resistance, hydraulic system reliability,