## 3 Analysis and Results
### Numerical Analysis of the Anchoring Performance of DBS Slips
#### 3.1.3 Anchoring Performance Tests of Dissolvable Ball Seat Slips  
To further investigate the anchoring performance discrepancies between nail-type and block-type slips (Figure 7), a servo-hydraulic universal testing machine was employed to conduct comparative tests on dissolvable ball seat slips under simulated downhole pressure conditions. The experiments aimed to quantify anchoring efficiency by evaluating the wear mechanisms of slip elements and casing wall integrity under equivalent setting loads, as defined by API RP \(11\)D1. Test results were then cross-validated against finite element analysis (FEA) simulations to calibrate numerical models. The experimental investigation was conducted according to the following methodology: (1) Experimental Design  
Comparative Analysis of Anchoring Damage: Under identical anchoring setting loads, a comparative evaluation was performed to assess the anchoring damage characteristics between slip nail and slip block configurations. Figure 6: Stress distribution along the casing wall for the two structural slip configurations. Casing Wall Damage Assessment: Under the same anchoring load conditions, the casing wall damage induced by slip nail and slip block mechanisms was experimentally examined and analyzed. (2) Test Apparatus and Materials  
The experimental setup included the following key components:  
A universal testing machine (Model: HDT106A, Serial No. : 1908112) was sourced from Hanzheng Testing Technology Co., Ltd., Guangzhou, China;  
Slip blocks and slip nails (see Figure 7 for illustrations);  
Data acquisition and processing equipment. The WYC Microcomputer-controlled high-pressure testing and monitoring system is presented in Figure 8. This automated pressure detection apparatus was designed for precision control across both high-pressure (100 MPa) and ultra-high-pressure (600 MPa) regimes. Experimental results demonstrated that the successful setting of the nail-type slip was achieved at 22 MPa, whereas a minimum setting load of 24 MPa was required for effective deployment of the block-type configuration. To ensure reliable setting performance across both designs, a standardized setting pressure of 24 MPa was selected for comparative evaluation in this study. (3) Experimental Testing Procedure  
1) Commissioning of equipment and tooling fixtures: We ensured that all equipment and fixtures were in optimal operational condition and properly calibrated for testing. 2) Preparation of equipment data acquisition system: We configured mechanical test parameters (e.g., loading rate, pressure thresholds) in the data acquisition system according to predefined protocols. 3) Loading process: We applied the specified setting force incrementally via the testing machine, with the load range strictly controlled between 0 and 40 MPa. We continuously recorded the stroke displacement of the sliding body within the range of 0 to 90 mm, ensuring the real-time monitoring of mechanical responses. 4) Collection and documentation of test results: We documented damage observations on slips and casing walls. We recorded the final anchoring status of the ball seat, referencing the anchoring mechanism schematic for comparative analysis. (4) Analysis of the Experimental Results  
The results of the comparative analysis via the slip anchoring test are as follows. As illustrated in Figure 9, the degree of damage to the casing inner wall was qualitatively analyzed through the application of the nail-type structure during the anchoring  
Figure 8: Anchoring performance test system. process. Stress concentration was observed in the casing wall at the locations where the slip nails were engaged with the casing. Consequently, severe damage was induced in the casing wall. Under the same loading conditions, less damage was inflicted on the casing wall by the block-type structure, which was demonstrated to be beneficial for maintaining the structural integrity of the casing.