Zibo Dongfeng Single-Cab Sludge Suction Truck (Blue License Plate, 5 m³) Government Procurement Case Study: Evolution from 'Adequate' to 'Optimal' — In municipal drainage system maintenance, sludge suction trucks are critical equipment for ensuring the smooth operation of a city’s 'underground circulatory system.' Between 2023 and 2025, a district urban management bureau in Zibo, Shandong (hereinafter referred to as 'a municipal sanitation department') conducted two rounds of sludge suction truck procurement—evolving from initial 'functional usability' to subsequent 'optimal performance.' This iterative demand evolution offers a representative reference for government procurement. This article reconstructs the case and, in conjunction with Chengli Special Purpose Vehicle Co., Ltd.’s solution, interprets how governments can maximize equipment effectiveness in procurement. I. First Procurement Round: Addressing the 'Availability' Requirement In March 2023, to tackle sludge removal tasks in aging urban pipelines, the municipal sanitation department procured three Dongfeng single-cab blue license plate sludge suction trucks (5 m³ capacity) for the first time. Consistent with local procurement practices, the total budget was capped at approximately RMB 607,000, with an average unit budget of around RMB 199,000. The winning supplier delivered base-specification vehicles: Dongfeng single-cab chassis, 5 m³ tank volume, equipped with a sewage suction pump and basic hydraulic system. Upon delivery, these vehicles initially met routine manhole cleaning requirements. However, practical usage gradually revealed several shortcomings: • Insufficient suction power: Low efficiency when handling sand-laden sludge, extending single-operation time by over 30%. • Difficult discharge: Absence of high-pressure rinsing nozzles at the rear of the tank resulted in severe residue after unloading, necessitating manual cleaning. • Cumbersome operation: Hydraulic system featured manual-only control, making operations tedious in confined spaces; additionally, no overflow alarm system was installed. In its quarterly summary report, the head of the department’s equipment division noted: 'The first batch resolved the question of 'availability,' but still falls short of 'optimal usability.' Especially during emergency rain-season sludge removal, frequent breakdowns and inefficient operations significantly impacted overall progress.' II. Evolving Requirements: Iterative Upgrade from 'Adequate' to 'Optimal' After over one year of operational feedback, the municipal sanitation department launched its second procurement round at the end of 2024, clearly specifying upgraded requirements: • Enhanced suction capability: Equipping with a high-capacity vacuum pump to ensure efficient suction even for sand-laden sludge. • Self-cleaning function: Installation of high-pressure rinse nozzles inside the tank to enable automatic post-unloading cleaning. • Intelligent operation: Hydraulic system must support remote control, plus liquid-level monitoring alarms and anti-overflow protection devices. • Unchanged chassis: Continued use of the Dongfeng single-cab blue license plate chassis to maintain C-class driver’s license compatibility and compliance with urban traffic restrictions. Budget-wise, consistent with local government procurement norms, the unit price increased to approximately RMB 220,000, bringing the total budget to roughly RMB 729,000 for three upgraded sludge suction trucks. In the open tender process, Chengli Special Purpose Vehicle Co., Ltd. won the bid, leveraging its proven expertise in sludge suction vehicle development to deliver a comprehensive solution meeting all upgrade requirements. III. Re-selecting Chengli: Detailed Overview of the Upgraded Solution Chengli Special Purpose Vehicle tailored the CLW5070GSSD6 sludge suction truck—based on the Dongfeng single-cab chassis—for this procurement (fully registered with complete technical parameters in the