What is the purpose of a center punch?

[VonKai]

A center punch is primarily used to mark the center of a circle or to create a starting point for drilling. Also known as a prick punch, it is made of high-carbon steel, typically 90~150mm in length, with a tip ground to either a 30°~40° or 60° angle and hardened through quenching. When using a center punch to mark a center point, first position the punch at an angle with its tip aligned to the center point. However, when striking, hold the punch upright, grip it firmly, and tap it gently with a hammer. Precautions for using a center punch: 1. Ensure the punch mark is accurately placed; the center must not deviate from the marked line. 2. The spacing between punch marks depends on the length and shape of the line being marked: sparse on straight lines, slightly denser on curves, and mandatory at intersections or turning points. 3. The punch mark at the center of a hole should be larger to facilitate easy alignment of the drill bit during drilling.

[Evelyn]

As someone who frequently drives to work, the oxygen sensor's main function is to monitor the oxygen content in the car's exhaust, helping the engine computer adjust the fuel-to-air mixture ratio for more efficient combustion. If it malfunctions, I notice my car's fuel consumption skyrocketing, reduced power, stronger exhaust odors, and frequent failures in emission tests. Over time, the engine may also develop carbon buildup, leading to difficulties during cold starts. During routine maintenance, I ask the mechanic to check if the sensor is clogged or aged—cleaning it every two years or so can save a lot on fuel costs. As a car owner, I consider it a silent hero, ensuring a worry-free and eco-friendly drive while reducing air pollution. It's quite practical.

[StCali]

As someone who frequently works on car repairs, I've seen a lot. The oxygen sensor is used to send signals to the engine control unit, measuring oxygen levels in real-time, and then the computer automatically adjusts the fuel injection to reduce emission pollution. When it fails, the car may shake, accelerate slowly, have high fuel consumption, and the dashboard will show a warning light. Testing is straightforward—just use an OBD scanner. Common issues include carbon buildup or wiring damage. Replacing it isn't difficult, but be cautious to work when the engine is cold to avoid burns. It also works in conjunction with the catalytic converter to reduce harmful gas emissions, making it more environmentally friendly. It's recommended to check it every 40,000 kilometers to prevent faults—saving money and ensuring safety.

[Doris]

I care about the environment. The oxygen sensor can make the car's emissions cleaner and reduce pollution. Its purpose is to measure the oxygen content in the exhaust, helping to optimize combustion and ensure emissions meet standards. During daily driving, it silently contributes to preventing air quality deterioration.