Case Study and Bid-Winning Solution Analysis of the National VI Dongfeng 3308 mm Wheelbase Sewage Treatment Vehicle in Tangshan Government Procurement In the municipal sanitation sector, sewage treatment vehicles serve as critical equipment for environmental protection initiatives; their selection directly impacts operational efficiency and the cost-effectiveness of fiscal fund utilization. This article takes a real procurement case from a municipal sanitation department in Tangshan as its entry point, integrating product data and verified delivery records from Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as 'Chengli') to comprehensively interpret volume selection, daily operation capacity calculation, and the winning bid solution for the National VI Dongfeng 3308 mm wheelbase sewage treatment vehicle—providing reference guidance for procurement units nationwide. I. Case Background: Procurement Requirements of a Municipal Sanitation Department in Tangshan District In 2025, the Urban Management Bureau of a district in Tangshan planned to procure a batch of sewage treatment vehicles to address local sewer network maintenance and emergency response needs. According to publicly released tender information, the procurement budget was capped at approximately RMB 1.14 million, targeting sewage collection, transportation, and preliminary treatment within urban areas and industrial parks. Following multiple rounds of technical evaluation and price comparison, Chengli Special Purpose Vehicle’s Dongfeng 3308 mm wheelbase sewage treatment vehicle solution emerged as the top choice. This solution complies with the National VI emission standard. The chassis is sourced from Dongfeng (e.g., model CLW5070GSSD6 series), while the superstructure is independently manufactured by Chengli. Customer feedback highlights the vehicle’s complete official certification, nationwide registration and annual inspection eligibility, and Chengli’s lifetime superstructure service support. Additionally, the Dongfeng chassis benefits from Dongfeng’s nationwide warranty network—significantly reducing operation and maintenance risks. II. Volume Selection: How to Choose Among 3 m³ / 5 m³ / 8 m³ / 12 m³ Configurations? Tank volume is the core parameter of a sewage treatment vehicle, directly determining its single-trip transport capacity. Different volumes suit distinct application scenarios: 3 m³ models are ideal for narrow streets or residential septic tank cleaning; 5 m³ is the mainstream choice for urban areas; 8 m³ and 12 m³ models are typically deployed in industrial parks or large-scale pipeline maintenance operations. Below is a comparative analysis based on Chengli’s product database: Volume | Recommended Chassis (Reference) | Application Scenario | Daily Operation Capacity (Reference) | Estimated Tax-Inclusive On-Road Price (2026) ---|---|---|---|--- 3 m³ | Dongfeng 3308 mm wheelbase | Street-level septic tanks, small sewage wells | ~20–30 tons | ~RMB 0.95–1.2 million 5 m³ | Dongfeng 3308 mm wheelbase | Urban pipeline maintenance, property-managed residential communities | ~30–45 tons | ~RMB 1.35–1.68 million 8 m³ | Dongfeng Dorica | Industrial parks, municipal trunk roads | ~50–70 tons | ~RMB 1.98–2.45 million 12 m³ | Dongfeng Tianlong | Large-scale wastewater treatment plants, emergency rescue operations | ~70–100 tons | ~RMB 2.4–2.98 million In this Tangshan case, the client selected a mixed fleet comprising two 5 m³ units and one 8 m³ unit—based on an average daily sewage generation volume of ~40 tons and an average transport distance of 15 km—effectively balancing routine operational requirements with fiscal budget constraints. III. Daily Operation Capacity Calculation Formula and Matching Table Actual daily operation capacity depends on loading time per trip, transport distance, unloading time, and round-trip frequency. Below is the standard formula for calculating daily operation capacity: Daily Operation Capacity (to