Government Procurement Case and Bid-Winning Solution Analysis for the Dongfeng Yizhan-Style Sewage Treatment Vehicle in Hohhot In northern frigid regions such as Hohhot, winter temperatures frequently drop to -20°C or lower. When municipal sanitation departments procure sewage treatment vehicles, their core concerns are not basic vehicle configurations—but rather equipment anti-freeze start-up performance, low-temperature hydraulic system stability, and comprehensive winter maintenance plans. In 2024, a municipal sanitation department (hereinafter referred to as 'the client') procured a batch of Dongfeng Yizhan-style sewage treatment vehicles for urban drainage network maintenance, ultimately selecting Chengli Special Purpose Vehicle Co., Ltd. for delivery. This article uses this case as a reference to comprehensively analyze the procurement process, selection criteria, and real-world operational feedback—providing practical insights for similar projects. I. Scenario Introduction: Department Head Initiates Requirement At the end of 2023, the sanitation department head of a district in Hohhot stated at the annual work meeting: “Severe sedimentation has occurred in parts of the city’s aging pipelines; existing equipment cannot operate effectively at -20°C. Last winter, the equipment failed twice due to hydraulic oil freezing.” He explicitly stipulated that newly procured sewage treatment vehicles must meet the following requirements: reliable engine start-up at -30°C, stable hydraulic system operation under low temperatures, and provision of a complete winter maintenance package. The budget was capped at approximately RMB 394,000 per unit (based on publicly available local tender information), with the quoted price covering full lifecycle service support. II. Internal Evaluation & Model Selection: Why the Dongfeng Yizhan-Style Was Chosen The client’s technical division held three internal review meetings, comparing five mainstream models available on the market. Key evaluation criteria included: • Anti-freeze Start-up Capability: Vehicles must be equipped with low-temperature preheating devices (e.g., fuel-fired heaters) to ensure successful one-time engine start-up at -30°C. • Low-Temperature Hydraulic Stability: The hydraulic system must use freeze-resistant hydraulic oil, and all hydraulic lines and pump housings must feature thermal insulation sleeves. • Winter Maintenance Plan: Suppliers must provide on-site services including periodic inspections, antifreeze fluid replacement, and battery maintenance. After comprehensive assessment, the Dongfeng Yizhan-style model stood out due to the following advantages: its chassis is based on the Dongfeng DOLICA D9 (e.g., model CLW5180GSSD6, compliant with official announcements), featuring a large-displacement engine with proven cold-start reliability; its superstructure is custom-built by Chengli Special Purpose Vehicle Co., Ltd., utilizing fully hydraulic drive and incorporating an electrically heated hydraulic oil tank. Ultimately, the client decided to procure four units, each priced at approximately RMB 340,000 (estimated according to local procurement practices). III. On-Site Inspection at Chengli’s Factory: Verification of Core Performance In March 2024, a five-member delegation—including technical and procurement staff—from the client visited Chengli Automobile Industrial Park in Suizhou, Hubei Province. Key verification tests included: • Low-Temperature Simulated Start-up: At Chengli’s laboratory, the vehicle was placed in a -35°C environmental chamber for 12 hours. After activating the preheating system, the engine started normally within 5 seconds, and hydraulic system pressure remained stable. • Hydraulic System Stability: Under simulated -20°C operating conditions, hydraulic oil viscosity showed no abnormal increase, and all working components—including the suction boom and sewage separation system—operated smoothly and responsively. • Winter Maintenance Pack