I. First Batch Procurement Experience: The 'Freeze-Blockage' Challenge In autumn 2023, a municipal sanitation department in a district of Urumqi procured three blue license plate, 5 m³ sewage suction trucks to address the cleaning and dredging needs of aging underground pipelines within its jurisdiction. Following local procurement practices, the budget for each unit was controlled at approximately X RMB, with Dongfeng single-cab chassis selected and superstructures supplied by a small-scale modification factory. Vehicles were delivered in November of the same year but quickly revealed serious issues under Urumqi’s winter conditions of -25°C: • Failure of frost-proof engine start-up: In the morning, engines failed to ignite normally due to frozen coolant and discharged batteries, causing an average delay of two hours per day in operations. • Hydraulic system failure: Hydraulic pumps and hydraulic oil lines experienced a sharp increase in viscosity at low temperatures, resulting in sluggish or completely jammed lifting and tilting actions—reducing dredging efficiency by approximately 60%. • Pipeline freezing: Sewage tanks and suction hoses lacked electric heating or thermal insulation layers; thus, internal ice formation occurred below -15°C, preventing normal drainage and requiring repairs up to twice per week. "Those trucks were virtually 'ornamental' during winter," recalled the head of the department’s equipment division. "We urgently contacted the original manufacturer, but they only offered basic suggestions—such as replacing hydraulic oil—and could not resolve the root cause." Ultimately, these vehicles completed less than 30% of the scheduled dredging tasks before March of the following year. II. Identifying Shortcomings and Evolving Requirements: Prioritizing 'Winter Adaptability' After enduring the first winter’s challenges, the department re-evaluated its procurement requirements in spring 2024, establishing the following core technical specifications: • Frost-proof engine start-up: Vehicles must reliably start at -30°C, equipped with cold-start assistance devices (e.g., glow plugs, battery insulation covers). • Low-temperature hydraulic stability: Hydraulic systems must use low-temperature-resistant hydraulic oil (pour point ≤ -35°C), supplemented with hydraulic oil heating units to ensure smooth operation. • Pipeline freeze protection: Sewage tanks and suction hoses must incorporate electric heating and thermal insulation layers to prevent icing. • Chassis–superstructure compatibility: Chassis must be Dongfeng single-cab (China VI emission standard); superstructures must be supplied by manufacturers with proven experience in low-temperature environments. According to publicly released tender information, the procurement budget remained at approximately X RMB per unit, covering five blue license plate, 5 m³ sewage suction trucks. III. Re-selecting Chengli: A Targeted Solution with Upgraded Vehicle Specifications Following comprehensive evaluations, the department ultimately chose Chengli Special Purpose Vehicle Co., Ltd.’s upgraded blue license plate, 5 m³ sewage suction truck (model reference: CLW5070GSSD6, derived from Dongfeng chassis). After thoroughly assessing Urumqi’s extreme climatic conditions, Chengli’s engineering team proposed the following targeted solutions: • Frost-proof start-up system: Standard configuration includes dual-voltage (12 V / 24 V) glow plugs, high-capacity low-temperature battery (Cold Cranking Amps ≥ 800 A), and engine coolant heater—enabling reliable cold starts down to -35°C. • Low-temperature hydraulic solution: Full-synthetic, low-temperature hydraulic oil (pour point -40°C) is used; an integrated 1.5 kW electric heating rod inside the hydraulic oil tank ensures operational temperature is reached within 10 minutes of preheating. • Pipeline thermal insulation design: All sewage and suction pipes are wrapped with self-regulating electric heat tracing tape and rubber-plastic thermal