Putting a "Golden Shield" on Insulators: Songjiang Power Supply Company Uses 3D Printing to Outsmart Squirrels

　　"It's in place — the protective shield fits snugly over the insulator!" At a 10 kV power line worksite at the foot of West Sheshan in Songjiang, technicians from the live-line work team of State Grid Shanghai Songjiang Power Supply Company were recently installing a self-developed "3D-printed small-animal-proof insulating shield" on an insulator. Precisely printed to match the insulator's contours, this protective shield acts like a snug "armor" for the power line, tightly isolating live parts from the outside environment. It prevents small animals from coming into contact with the live parts without causing them any harm. This scene vividly illustrates how the Songjiang Power Supply live-line work team is using 3D printing technology to solve operational and maintenance challenges.

　　It is understood that power distribution line equipment comes in a wide variety, and on-site conditions vary greatly. Protecting components such as insulators and line clamps often requires specialized parts with non-standard dimensions. In the past, work crews could only rely on off-the-shelf parts or outsourced custom manufacturing, which involved long lead times, high costs, and difficulty achieving a perfect fit, significantly compromising the effectiveness of the protection. Squirrels are a frequent presence in the Songjiang forest area, and incidents of tripped circuit breakers caused by them gnawing on wires occur from time to time, rendering traditional protective measures inadequate. "If we lack suitable 'armor', we'll make it ourselves!" declared Wang Junhao, a technical expert on the live-line work team, with determination.

　　In early 2025, Wang Junhao led the formation of an innovation task force, and the company equipped the team with specialized 3D printing equipment. Starting from the ground up, the team scanned and modeled common equipment such as circuit breakers and insulators one by one, building a comprehensive library of 3D digital models. With this "toolbox" at their disposal, the team was able to quickly design and print components that perfectly fit different insulator models and meet various protection requirements.

　　To address the problem of squirrel gnawing, the team conducted repeated observations of the biting force and habits of rodents. They screened dozens of polymer materials to select varieties that are insulating, flame-retardant, vibration-resistant, and durable, and continuously adjusted the hardness, thickness, and edge curvature of the protective covers to ensure they effectively prevent gnawing without causing accidental injury to the animals. The final "small-animal-proof insulating shield" is compatible with 85% of the 10kV line insulators in the Songjiang power grid. It is easy to install, fits snugly, and truly achieves the goal of "one shield protecting one line".

　　The advantage of rapid prototyping through 3D printing has freed the team from reliance on external supply chains. The process, from design to printing the finished product, has been reduced from weeks to just a few hours, and iterative improvements have become effortless. With this "armor", the risk of circuit breakers tripping on power lines in forested areas has dropped significantly, and power supply reliability has improved markedly. At the same time, the team has extended the use of 3D printing technology to emergency repairs: when insulation is damaged by strong winds, lightning strikes, or tree branches contacting power lines, they take photos on-site and transmit the parameters of the damaged area back to headquarters. They then rapidly print emergency shielding components and use insulated poles to cover the damaged points from a distance, enabling rapid restoration of power. As a result, the average time to restore power has been reduced by 23% compared to previous practices.

　　Since its implementation in June 2025, Songjiang Power Supply Company has designed 17 types of 3D-printed components, filed 2 utility model patent applications, carried out 4 temporary repairs for power line faults, and reduced the trip rate caused by external damage to power lines by 20% year-over-year. From the insulator protective shield to various custom-made emergency components, this innovation team rooted in the front line is using 3D printing as its "brush" to sketch a new vision of "smart inspection and maintenance" on the canvas of distribution network operations, safeguarding every inch of the power grid's security and ecological harmony through concrete actions.