I. Case Background: Pain Points and Requirements for Winter Sludge Removal Operations in Taiyuan Taiyuan’s winter temperatures frequently drop below -10°C. Conventional sludge suction trucks often suffer from difficult cold starts and sluggish hydraulic system response under low-temperature conditions—severely impacting the efficiency of municipal drainage network maintenance. In 2025, a municipal sanitation department launched a public tender to procure a batch of blue-license-plate, 3-cubic-meter sludge suction trucks for cleaning 3 km of aging pipelines within its jurisdiction. After multiple rounds of evaluation, Chengli Special Purpose Vehicle Co., Ltd. delivered Dongfeng double-cab chassis-based sludge suction trucks (reference model CLW5070GSSD6, per official announcement parameters), equipped with an efficient frost-proof starting system and low-temperature hydraulic stabilization device. According to local procurement practice, the unit price of these vehicles was approximately RMB 110,000 (per publicly available tender information), with a total budget capped at around RMB 341,000 for three units. II. Performance Comparison Before and After Deployment The following operational data were provided by an environmental maintenance unit for a specific street, comparing conventional sludge suction trucks versus Chengli sludge suction trucks during winter operations (data period: December 2025 – February 2026). Metric | Conventional Sludge Suction Truck (Pre-Deployment) | Chengli Sludge Suction Truck (Post-Deployment) | Improvement ---|---|---|--- Average Daily Output (m³/unit) | 12 | 22 | +83% Average Startup Time (minutes) | 15 | 5 | -67% Fault Rate per Operation (%) | 8 | 1.5 | -81% Fuel Consumption per Operation (liters) | 18 | 14 | -22% Operators Required per Unit (persons) | 3 | 2 | -33% Source: Data compiled by the municipal sanitation department; referenced from acceptance reports included in the public tender documentation. The Chengli sludge suction truck reduces startup time to under 5 minutes in low-temperature environments, thanks to its frost-proof preheating system (refer to the low-temperature configuration options specified in the CLW5070GSSD6 official announcement). III. Increase in Average Daily Output: Breakthrough from 12 m³ to 22 m³ Under extreme weather conditions of -15°C in Taiyuan, conventional sludge suction trucks experience reduced vacuum pump efficiency due to increased hydraulic oil viscosity, limiting daily output to approximately 12 m³. By contrast, the Chengli sludge suction truck employs low-temperature hydraulic stabilization technology, enabling its hydraulic system to maintain over 80% efficiency even at -20°C. According to customer feedback, the average daily output per unit remains stably above 22 m³, reaching up to 25 m³ during peak periods. This means that three Chengli units can cover the workload previously handled by five conventional units—significantly shortening pipeline maintenance cycles. IV. Optimization of Personnel Allocation: Reduction from 3 to 2 Operators Conventional sludge suction trucks require one driver, one operator, and one auxiliary worker—totaling three personnel per unit. The Chengli sludge suction truck features an integrated control system, allowing the operator to perform suction and discharge operations via a joystick inside the cab—eliminating the need for additional support staff. In actual application by a district urban management bureau, only two personnel (driver兼operator) are required per unit to complete all tasks. Based on local labor cost calculations, each unit saves approximately RMB 60,000 annually in labor expenses (per labor-cost estimation methodology outlined in the public tender documentation). For three units, annual labor savings amount to roughly RMB 180,000. V. Reduction in Operating Costs: Lower Fuel Consumption and Maintenance Expenses Thanks to the fuel-efficient design of the Dongfeng chassis (compliant with China VI emissi