Solution

III. Core Challenges

The pain points faced by the customer in large-scale production directly restricted its market competitiveness, specifically manifested in:

1. High loss caused by clamping and positioning deviation: Manual alignment of blanks with dial indicators relies on operators’ experience, which not only takes up to 5 minutes for clamping on a single machine tool but also only achieves a positioning accuracy of ±0.1mm, unable to offset the impact of uneven machining allowance of blanks. Previously, the average monthly scrap of blanks due to insufficient machining allowance and dimensional out-of-tolerance reached more than 300 pieces. Based on a single blank cost of 150 CNY, the annual loss cost exceeded 540,000 CNY.
2. Lag and limitations of offline inspection: Offline inspection only samples 5% of batches, failing to capture dynamic variables such as machine thermal deformation, tool wear and blank tolerance fluctuation in real time. There was an incident where concentricity of more than 1,000 products in a batch was out of tolerance (>0.1mm) due to thermal deformation of the machine tool spindle. The problem was only found during offline inspection after all products were machined, resulting in a direct loss of over 150,000 CNY, affecting the delivery schedule for automakers and exposing the customer to the risk of liquidated damages.

Consistency challenge in multi-batch production: The customer needs to switch more than 20 wheel hub models every month. In the traditional mode, alignment parameters need to be re-tuned after each model change, with a debugging cycle of 2-3 hours. Moreover, debugging accuracy varies among different operators, leading to large consistency deviations in key dimensions of the same model products, with a complaint rate of 3% from automakers.

IV. Solutions

Targeting the customer’s core pain points, our company set up a special technical team and customized an integrated solution of Machine Tool Touch Probe + Exclusive Measurement Software based on the equipment parameters of the customer’s 10 Vertical Machining Centers (Model: VMC850) and wheel hub machining processes. The solution achieves full-process coverage of pre-machining datum calibration and in-process dynamic monitoring, with specific measures as follows:

Rapid model change adaptation for multi-models (Added): A model database is customized for the customer, with measurement points, compensation logic and tolerance standards of different wheel hubs pre-set in the system. Only the corresponding model program needs to be called on the machine tool operation panel during model change without re-debugging, compressing the model change time from 2-3 hours to within 15 minutes and greatly improving production flexibility.

Dynamic compensation system for clamping and positioning: After blank clamping, the machine tool automatically triggers the probe measurement program. The probe accurately collects 4 evenly distributed feature points on the inner wall of the wheel hub center hole through a ruby stylus, and the system calculates the actual center coordinates through fitting. It simultaneously detects 5 datum points on the mounting end face (including edge and central areas), analyzes the flatness and height deviation of the end face, and generates complete positioning deviation data. The system real-timely compares the measured data with the theoretical programming coordinates, automatically generates X/Y/Z three-axis compensation parameters and uploads them to the machine tool control system. The entire process requires no manual intervention, stably controlling the clamping datum positioning accuracy within ±0.02mm.

Real-time in-process monitoring (Added): For high-value wheel hub models, an additional random inspection function for key dimensions during machining is configured. The probe automatically measures core dimensions such as bore diameter and step height after rough machining and before finish machining. If dimensional deviation exceeds the preset threshold (±0.03mm), the system immediately pauses machining and triggers an alarm, and simultaneously provides tool wear compensation suggestions to avoid the production of batch non-conforming products.

V. Application Achievements

With the implementation of the DOP40 Machine Tool Touch Probe, the customer has achieved significant breakthroughs in three dimensions: quality, efficiency and cost, with specific results as follows:

Significant reduction in production costs: The blank scrap rate is reduced from the original 0.75% to 0.1%, reducing the monthly scrap loss by about 45,000 CNY and saving more than 540,000 CNY in annual costs. The offline inspection workload is reduced by 70%, freeing 2 inspectors to core production positions and indirectly reducing labor costs by 15%. Tool wear is more uniform due to dynamic compensation, extending tool service life by 20% and further reducing consumable costs.

Dual improvement in quality precision and consistency: The concentricity of key wheel hub dimensions is optimized from the original 0.1mm to 0.04mm, the end runout is controlled within ±0.03mm, and the qualification rate of core dimensions is increased from 96.5% to 99.8%. The dimensional fluctuation range of multi-batch products is reduced by 60%, the complaint rate from automakers is lowered to below 0.2%, and the customer has successfully passed the upgraded certification of High-Quality Supplier by a joint-venture automaker.

Substantial optimization of production efficiency: The clamping and alignment time of a single machine tool is compressed from 5 minutes to less than 45 seconds, with a 22% increase in production capacity per shift (8 hours). The efficiency of multi-model change is improved by 87.5%, enabling the customer to undertake 3-5 more small-batch orders monthly, and the capacity utilization rate is increased from the original 85% to 95%.

VI. Customer Evaluation

“The machine tool touch probe solution from Qidu has accurately resolved the contradiction between precision and efficiency in our large-scale production. The automation and high precision of clamping and positioning have completely freed us from reliance on skilled operators, and the steady improvement in the qualification rate of key dimensions has made us more competitive in supporting automakers. The customized service and rapid response of the technical team have given us a profound experience of professional technical support, and Qidu is a worthy long-term cooperation partner.”— Mr. Zhang, Production Technology Director of the Customer