What precautions should be taken when cutting and drilling galvanized square pipes during installation?
For cutting, it is recommended to use an abrasive cutter or plasma cutter (to avoid oxygen cutting and burn the zinc coating). For drilling, use a bench drill or hand drill. After drilling, apply zinc paste to the cut and hole to prevent rust on the exposed steel.
What are the methods for connecting galvanized square pipes?
Common methods include: welding (using galvanized welding wire and applying zinc paste after welding), bolting (using hot-dip galvanized bolts to prevent contact corrosion), and sleeve connections (suitable for pipes, with sealant to prevent leaks). Bolts are recommended for outdoor connections to avoid damaging the zinc coating.
How can I enhance stability when installing outdoor galvanized square pipe railings?
The bottom of the column should be buried in concrete (depth ≥ 30cm, concrete strength C20), or fixed to the ground with expansion bolts (bolt diameter ≥ 12mm, at least two bolts per column). For large railing spans (> 2m), additional intermediate supports are required. If galvanized square pipes develop localized rust after long-term use, how should they be treated?
First, remove the rust (use sandpaper or pickling to remove rust, avoiding damage to the surrounding zinc layer). Then, use alcohol to clean the surface oil. Finally, apply a zinc-based coating (such as zinc paste or zinc powder paint) to a thickness close to the original zinc layer to ensure effective protection.
If galvanized square pipes are used as water pipes, what pre-installation treatment is required?
First, flush the pipe interior (to remove zinc slag and dust left over from production). Check the interior for smoothness (no burrs to prevent water flow resistance or blockage). Use food-grade sealant when making connections (to avoid contamination of the water with standard sealants). After installation, perform a hydrostatic test (testing pressure resistance, ≥ 0.6 MPa, maintaining pressure for 30 minutes without leakage).