Interpretation of the Government Procurement Case and Winning Bid Solution for the CN6 Dongfeng 3308 mm Wheelbase Sewage Treatment Vehicle in Shijiazhuang In northern regions—especially cities like Shijiazhuang—low winter temperatures impose stringent requirements on specialized vehicles’ starting performance, hydraulic system reliability, and overall operational stability. At the end of 2023, a municipal sanitation department in Shijiazhuang publicly procured a batch of CN6-emission-standard sewage treatment vehicles, primarily intended for rapid handling of rainwater/sewage pipelines, septic tanks, and riverbed sludge. Following multiple rounds of evaluation, Chengli Special Purpose Vehicle Co., Ltd. secured the contract by demonstrating outstanding capabilities in cold-weather starting, low-temperature hydraulic stability, and localized after-sales support—and successfully delivered multiple sewage treatment vehicles built on the Dongfeng 3308 mm wheelbase chassis. Based on publicly available tender information and user feedback, this article provides an in-depth analysis of the case to serve as a reference for similar procurement projects. Project Basic Information Procuring Entity: A Municipal Sanitation Department in Shijiazhuang Project Scope: Procurement of CN6-emission-standard sewage treatment vehicles for pipeline cleaning, sludge suction, and solid-liquid separation operations Budget Control: According to publicly disclosed tender information, the total project budget was capped at approximately RMB 1.985 million, with an estimated unit cost of around RMB 496,000 per vehicle. Delivery Timeline: Delivery and acceptance to be completed within 30 calendar days after contract signing. Key Requirements: Vehicles must operate reliably under Shijiazhuang’s winter conditions (–15°C to –20°C), featuring cold-start capability, stable hydraulic system performance at low temperatures, and complete regulatory documentation enabling normal registration, annual inspection, and commercial operation. Winning Bidder: Chengli Special Purpose Vehicle Co., Ltd. (Model: CLW5070GSSD6 Sewage Treatment Vehicle, based on Dongfeng 3308 mm wheelbase chassis) The project adopted an open tender process. Chengli won the bid by offering a compelling after-sales service commitment—'factory-authorized nationwide warranty for the chassis and lifetime service for the superstructure'—alongside a professional configuration package tailored specifically for northern climatic conditions. According to customer feedback, the delivered vehicles achieved successful single-attempt starts even at –18°C, exhibited no hydraulic system jamming or sluggishness, and demonstrated approximately 15% higher operational efficiency compared to comparable products. Analysis of Chengli’s Winning Bid Reasons Based on publicly available tender documents and Chengli’s bid submission, the key reasons for its success include: 1. Outstanding Cold-Start Performance Shijiazhuang’s winter temperatures frequently drop below –10°C, causing conventional sewage treatment vehicles to suffer from battery discharge, diesel waxing, and coolant freezing. The CLW5070GSSD6 model supplied by Chengli features the following standard cold-weather configurations: • Low-Temperature Battery: Rated capacity of 180 Ah, delivering over 30% higher discharge efficiency at –20°C compared to standard batteries; • Fuel Heating System: Integrated into the fuel supply line, capable of preheating diesel to –35°C levels to prevent waxing; • Antifreeze Coolant Circulation Heater: Preheats engine coolant to rapidly raise cylinder block temperature. These features ensure reliable vehicle startup even at –20°C, fully meeting the core requirements of northern procurement entities. 2. Low-Temperature Hydraulic Stability Solution The core working components of sewage treatment vehicles—including sludge pumps, separation systems, and lifting mechanisms—all rely on hydraulic power. At low temperatures, hydraulic o