Government procurement case of the Deyang Dongfeng double-cab sludge suction truck (blue license plate, 3 m³ capacity): Failure rate analysis and bid-winning solution interpretation. In daily municipal sanitation operations, sludge suction trucks—critical equipment for unblocking pipelines and removing sediment—directly impact operational efficiency through their reliability and after-sales support. This article analyzes maintenance records, failure type distribution, after-sales response time, and spare parts supply assurance for three Dongfeng double-cab blue-plate sludge suction trucks (3 m³) over a three-year service life, providing objective reference data for similar procurement decisions. I. Project Background and Procurement Overview At the end of 2022, a municipal sanitation department in Deyang launched a procurement plan for three Dongfeng double-cab blue-plate sludge suction trucks (3 m³ capacity) to enhance urban drainage system desilting efficiency. Following local procurement practices, the total budget was controlled at approximately RMB 334,000, with an estimated unit price of around RMB 100,000 (based on publicly available tender information). Ultimately, Chengli Special Purpose Vehicle Co., Ltd. delivered three Dongfeng double-cab blue-plate sludge suction trucks, equipped with Dongfeng-series chassis and Chengli-designed proprietary sludge suction systems. The complete vehicles comply with China VI emission standards. These vehicles are primarily deployed for cleaning silted material from urban stormwater and sewage pipelines, inspection chambers, and river channels, operating an average of 6–8 hours per day and covering approximately 20,000 km annually. To date, the vehicles have been in service for three years, accumulating roughly 60,000 km in total mileage, and have generated comprehensive maintenance and after-sales service data. II. Three-Year Real-World Maintenance Records and Failure Type Distribution According to Chengli’s after-sales service archives and customer feedback, the three sludge suction trucks experienced a total of 17 maintenance events over the three-year period: 12 related to the superstructure system and 5 to the chassis. The specific failure type distribution is as follows: Failure Type | Number of Occurrences | Percentage (%) | Typical Symptoms | Primary Causes ---|---|---|---|--- Hydraulic System Failures | 5 | 29.4% | Cylinder seal leakage, hydraulic hose fitting seepage | Prolonged high-load operation causing natural aging of seals Sludge Auger Jamming | 3 | 17.6% | Hard objects (stones, branches) jamming auger blades | Complex working environment with foreign object intrusion PTO and Pump/Valve Failures | 2 | 11.8% | Difficulty engaging PTO, insufficient hydraulic pump pressure | Frequent operation leading to gear wear Electrical System Failures | 2 | 11.8% | Poor control panel contact, sensor malfunction | Moisture ingress into wiring or loose connectors Chassis Engine Failures | 3 | 17.6% | Unstable idle speed, emission warning light activation | Variability in fuel quality and insufficient routine maintenance Chassis Brake System Failures | 2 | 11.8% | Excessive brake pad wear, increased stopping distance | Frequent start-stop operation on work routes Total | 17 | 100% | — | — Superstructure failures account for 70.6%; chassis failures account for 29.4%. Data indicate that superstructure-related failures dominate, with hydraulic system failures and sludge auger jamming collectively representing 47% of all incidents—directly attributable to the vehicle’s prolonged high-load operation and exposure to complex, abrasive media. Chassis failures mainly involve the engine and braking system, accounting for 29.4%, consistent with typical wear-and-tear patterns. III. Chengli After-Sales Response Speed and Resolution Effectiveness For all 17 maintenance events, Chengli’s after-sales team adhered to the following response standards: Emergency Failures (