Case Background: Sewage Treatment Vehicle Procurement Requirement of a Municipal Sanitation Department in Yancheng City In 2024, a municipal sanitation department in Yancheng City (hereinafter referred to as 'the client') faced insufficient local sewage treatment capacity and thus required procurement of a yellow-plate sewage treatment vehicle for routine septic tank cleaning, sewer pipeline unclogging, and emergency response. According to publicly released tender information, the client initially planned to procure a sewage treatment vehicle built on a 3308 mm wheelbase chassis, with a budget capped at approximately RMB 396,000. Key requirements included high-efficiency suction, solid-liquid separation, automatic discharge functionality, and suitability for intensive daily operation of 6–8 hours. After multiple rounds of evaluation, Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as 'Chengli') successfully delivered the equipment. Feedback from the client’s management indicated that, following commissioning, the vehicle increased average daily sewage processing volume by approximately 30%, while its failure rate remained significantly lower than anticipated. This article provides an in-depth analysis of the case from four perspectives: core pain points under daily high-load operation, equipment fatigue management, Chengli’s heavy-duty operational design, and a Frequently Asked Questions (FAQ) section. I. Core Pain Points Under Daily High-Load Operation For sanitation departments, sewage treatment vehicles typically operate under continuous, high-intensity conditions. For example, in routine operations conducted by an environmental maintenance unit on a certain street in Yancheng, a single vehicle may need to service 10–15 septic tanks or sewer manholes per day, with individual suction cycles lasting up to two hours. Prolonged high-load operation commonly leads to the following issues: • Declining suction efficiency: Accumulation of debris inside the sewage tank causes overheating of the vacuum pump or hydraulic system, extending suction time from 15 minutes to over 30 minutes. • Wear of critical components: High-pressure water pumps, pipelines, and sealing elements are prone to leakage or blockage during continuous use, resulting in frequent repairs. • Mismatch between chassis and superstructure: Chassis of some low-specification models lack sufficient load-bearing capacity; prolonged overload operation leads to frame deformation or suspension aging. • Delayed emergency response: Sudden equipment failures—coupled with limited access to rapid repair services—disrupt operational schedules. In this case, Chengli’s team identified, through preliminary on-site surveys, that the client’s daily operating mileage totals approximately 80 km, and that operations frequently traverse narrow streets in older residential neighborhoods. Consequently, chassis stability and superstructure durability were prioritized during vehicle selection. II. Equipment Fatigue Management: How Chengli Extends Service Life To address high-load operational demands, Chengli implemented multiple measures for equipment fatigue management: • Chassis Selection: A yellow-plate chassis compliant with China VI emission standards (referencing CLW-type official announcement parameters) was adopted, featuring a 3308 mm wheelbase, larger-load-rated tires, and reinforced suspension. The chassis is covered by nationwide factory warranty, ensuring prompt local maintenance support in Yancheng. • Superstructure Reinforcement: The sewage tank is fabricated from high-strength steel plates with internal anti-corrosion coating; its single-cycle capacity is optimized to approximately 15 m³, aligned with regional procurement conventions. The vacuum pump and hydraulic system have been upgraded to industrial-grade specifications, designed for a service life exceeding five years. • Intelligent Monitoring: Level sensors and temperature monitoring modules have been