People usually take the train, either staring at their phones or admiring the scenery outside the window. Few of them look down at the piece of wood they are stepping on. But it is this seemingly dull and unremarkable piece of wood that carries hundreds of tons of trains, exposed to the sun and rain, and has to ensure that it does not rot or loosen for decades.

Why?

Just rely on its' oil ', and the' oil 'level is very high.

Let's talk today about how an ordinary pine wood is refined into "armor grade anti-corrosion".

First, let me ask a question: What would you do if you had a piece of wood and wanted it to resist corrosion?

Many people's first reaction may be: painting.

Brush a layer of anti-corrosion oil on the wood, like waxing leather shoes, to make the surface shiny and look reassuring. This practice is indeed common, such as fence posts at home and wooden chairs outdoors, many of which are done this way. Fast speed, low cost, immediate effect after brushing, looks beautiful.

But if railway sleepers do the same, then they are playing rogue.

Think about it, sleepers are buried in crushed stone ballast, on top of which are railway tracks and trains, bearing dozens of tons of vibration and pressure every day. Over time, wood is inevitably prone to cracking and deformation. Once there is a crack, rainwater, moisture, and insect eggs will drill into it. At this point, the layer of oil you're brushing on the surface is like a piece of paper sticking to a window, easily torn with a poke. Rainwater flows straight into the cracks, and the interior of the wood is still in a "pure natural, additive free" state. Fungi and insects are like celebrating Chinese New Year when they see it, so they invite their friends to party.

In a few years, this sleeper looks okay on the outside, but inside it has rotted into a hollow.

So, the anti-corrosion of railway sleepers does not follow the "surface light" route, but the "penetrating heart" route.

This process, in our jargon, is called 'oil immersion treatment'.

How to soak? Not with a brush or a spray can, but by stuffing the processed pine wood (usually defatted, dried, ensuring an empty stomach and ready to eat) into a huge, pressure cooker like sealed jar.

Close the door, evacuate, and remove all the air from the can.

Then, start injecting anti-corrosion oil into the jar while applying tremendous pressure.

At this point, you can imagine that this piece of wood is a seasoned foodie who has been hungry for several days. The atmospheric pressure outside is like a pair of invisible hands, pouring anti-corrosion oil desperately into the depths of the wood and stuffing it recklessly. It doesn't stick to the surface, but permeates into every fiber and pore deeper in the wood.

How harsh is this process?

A reference indicator is that the depth of immersion in oil often reaches 13 millimeters or more.

What is the concept of 13mm? Take a ruler and see, it's over one centimeter. For a sleeper, this soaking layer is equivalent to creating a suit of armor from the inside out. It is not a plastic film attached to the surface, but integrated with the wood itself, becoming a part of the wood.

In the future, even if the surface of the sleepers cracks due to wind and sun exposure during use, it won't matter. Because what is exposed in the cracks is not fresh and fragile wood fibers, but "oil wood" that has been soaked countless times with anti-corrosion oil. The bug looked at it and saw that this thing had a diesel smell, as hard as bacon, and couldn't chew. Goodbye!

Fungi look: This environment is oily and cannot take root. Withdraw!

This is the mystery of "armor": it is not carried by the shell, but by turning every inch of "flesh" into armor.

So you see, the self-cultivation of a wooden sleeper is so simple and boring - being locked in a big jar, vacuumed, high-pressure oiled, and finally turning into a "real, oil salt free" hard core wood.

It sacrificed its "simplicity" (pure natural wood) for a whole body of "oiliness" (deep anti-corrosion), and then lay quietly in the ballast, carrying dozens of tons of trains day after day, year after year.

What does' excess oil 'mean?

This is it.