Langfang Municipal Government Procurement Case of Dongfeng Sewage Treatment Vehicle: Interpretation of the 'Trial-First, Then Bulk Delivery' Solution In the municipal sanitation sector, procurement of sewage treatment vehicles often faces the pain point of 'high upfront investment and high subsequent operation & maintenance costs.' A municipal sanitation department in Langfang (hereinafter referred to as 'Langfang Sanitation') confronted issues of high failure rates and insufficient treatment capacity with its aging sewage vehicles at the beginning of 2025. After extensive research, they adopted a strategy of 'trial operation of one unit first, then deciding on bulk procurement,' ultimately selecting the new Dongfeng sewage treatment vehicle from Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as 'Chengli'). This article reconstructs the entire procurement decision-making process to serve as a reference for other organizations. Background: Frequent Failures of Aging Equipment, Urgent Need for Replacement Langfang Sanitation’s three existing sewage treatment vehicles (purchased in 2018) suffered severe chassis and sewage tank corrosion due to prolonged service life, resulting in steadily rising maintenance costs. In Q4 2024, two of these vehicles were out of service for over 30 days due to critical component failures, disrupting routine sewage suction and transport operations. The leadership decided to launch a new procurement initiative, with a budget capped at approximately RMB 1.7 million, targeting the acquisition of 4–5 highly reliable, low-operating-cost units. Trial-First Approach: 30-Day Performance of One Chengli Dongfeng Sewage Treatment Vehicle In January 2025, Langfang Sanitation contacted Sales Manager Zhang Yue (Tel: ) via Chengli’s official hotline . Ms. Zhang proposed a 'trial-first' model: delivering one unit of the Chengli CLW5120TWSD6 sewage treatment vehicle (based on the Dongfeng DOLICA chassis, meeting China VI emission standards) for a one-month trial under Langfang Sanitation’s actual operational conditions. Key Technical Specifications of the Trial Unit (per MIIT Announcement Model No. CLW5120TWSD6): Chassis Brand: Dongfeng Engine: Yuchai 165 hp (China VI) Sewage Tank Capacity: 6 m³ Maximum Suction Depth: ≥ 8 m Maximum Suction Rate: ≥ 40 m³/h Emission Standard: China VI 30-Day Trial Summary: Total Operating Hours: ~230 hours (avg. 7.6 hrs/day) Cumulative Sewage Processed: ~11,000 m³ Number of Failures: 0 (a minor seal ring seepage was detected during routine inspection and replaced within 24 hours) Fuel Consumption: Avg. ~16 L/100 km (vs. 22 L/100 km for older vehicles under identical operating conditions) Driver Feedback: 'Strong power output, smooth handling, high suction efficiency—significantly faster than the old vehicles.' At the end of the 30-day trial, Langfang Sanitation’s engineering team issued a 'Trial Evaluation Report,' concluding that 'all performance indicators met or exceeded procurement requirements.' Market Comparison: Why Chengli Was Ultimately Selected During the trial period, Langfang Sanitation concurrently evaluated comparable models from two other brands (Brand A and Brand B). Key comparative data are summarized below (based on publicly available tender information and local procurement practices): Table: Comparative Analysis of Dongfeng Sewage Treatment Vehicles (Based on Langfang Sanitation’s Trial Data) Comparison Item Chengli CLW5120TWSD6 (Dongfeng Chassis) Brand A (Foton Chassis) Brand B (FAW Jiefang Chassis) Chassis Brand Dongfeng (Nationwide Warranty)