Why do we need to irrigate with sand? Also, how to pack a tent

Answer: The purpose of adding sand inside is to prevent the aluminum tube from collapsing and forming dead bends. Inserting steel bars into the aluminum tube under stress is also a way to increase strength.
Tent packaging issue
Perhaps some people think tent packaging is a small matter, but it actually involves the interaction between equipment manufacturers and users.
If you have often watched videos of outdoor activities outside, be careful to note that their tents are all inside the backpack, not hanging outside the backpack like we do. If you use foreign made tents, you will find that the biggest difference between them and domestic tents is that the tent pillars and the tent cloth are packaged separately, folded well, and their volume size matches the diameter of the backpack's inner circumference, so that the tent cloth can be placed inside the backpack, while the tent pillars are inserted on both sides of the backpack. This is the concept of foreign designers and considering the user. In the past, aluminum frame backpacks with external frames had little problem with tent packaging, but now mainstream inner frame straight backpacks are difficult to carry the tent packaging method designed in China. It is not immutable, as long as you give up the constraints designed by the original manufacturer for consumers, you can naturally carry it comfortably.
The common practice for most people is to discard the original tent jacket and use a sleeping bag cover or waterproof sleeping bag cover to cover the inside and outside of the tent. This way, the tent will not appear outside the backpack. Walking for such a long distance or in intermediate mountains will not have the problem of a backpack with a tent that is too long and wide. Imagine the backpacker hanging the tent vertically on the backpack, looking like tying meat dumplings, and placing it horizontally on the backpack, but also afraid of hitting tree trunks or falling trees.