Laying YDY Cable in Conduit Underground vs YKY Cable's Durability and Safety

Hello, I know that it has already been rolled, but I would like to ask how incorrect it is to lay the YDY type cable in a conduit, seal the ends of the conduit with polyurethane foam and bury it in the ground. I know that for laying underground cables, YKY cables should be used, protecting them against mechanical damage and additionally marking them against accidental digging. I am wondering, however, because YDY cables have an average operating temperature characteristic of -40 +70, YKY cables -30 +70. Both types of these wires and cables have polyvinyl insulation and sheath. It is true that YDY cables are poorly resistant to moisture and their insulation can crack, which can cause short circuits, leakage of current to the ground and energy losses. But I have a question if any of you pulled out such a cable damaged by moisture and it did not look very special. Besides, I would like to ask if the YKY cable should be additionally inserted into a conduit or a tube. Will this only worsen heat dissipation and is a bit exaggerated.

Regards

I had cases where the YDY, suspended high in the hall, broke. Gaps up to 1mm were formed. It was caused by large temperature fluctuations, high humidity also did its job. The quality of the material was to blame, but it was beyond your control.
Write what is to power this cable, where and under what conditions it will be placed and why the fear of overheating.

In my opinion, it does not make much sense to insert the cable (YKY) additionally to the tube. cables should be used outdoors. Looking at it from a different angle, in the event of damage to the YdY cable, maybe even some kind of shock (in extreme cases), the person who allowed the cable to be placed in the wrong place could have problems.

I saw YDY stacked in the ground in protective tubes. Usually for powering not very large loads - e.g. for lighting garden. They've always been damn gentle and sensitive. Remember that the earth "works" all the time.
Though YDY and YKY are roughly the same. then the YKY is much more durable. If you're going to replace the installation in a year or two, then YDY might be. However, if you do not want to bother with the installation again and not have any problems with it, it is better to put YKY right away.
Even as a contractor, take into account that in the event of a failure, the customer will take the installation first. If, for example, due to a damaged cable, an expensive receiver recommends him (e.g. a videofon for a few thousand), he may even charge you with costs.
As the owner of the installation, take into account that the need to replace a cheap installation in a short time may exceed the cost of a more expensive installation, but in harmony with the art.

Already translators. The YDA cable has been laid in the ground in the conduit for a year. It is used to power the garage, it is a 4x2.5mm cable secured with a 16 A circuit breaker. It is 30 meters long. But I didn't know about it, I put such a cable because I just had one. It is on my private plot so I can only blame myself when it falls apart. If I had read it before, I would have buried the YKY. Sometime in the early 90s, due to material difficulties, I saw myself when the flat YDYp cable was buried, and certainly not earthen, because it was white without any cover directly in the ground. Interestingly, it works to this day, in what condition the insulation is, I do not know. We'll probably find out when he starts throwing fuses because the insulation will fall apart.

Added after 7 [minutes]:

Oh, and one more thing, I ask you what conclusions can be drawn from your practice whether the YDY laid in the ground in a pecheal really degrades so quickly that you have to replace it in two years because I'm useless. If so, it might be worth trying to get it out of this tube (although it probably won't work) and insert the right YKY.

I have an old "outhouse" on my plot. It comes from the time when the plot differed from the cultivated field only by a fence. A regular tin garage was built as a temporary flat. It was equipped with a lighting installation and a socket. From the garage, I pulled the power supply to the "privy" so that when they got drunk at night, I would not sit in the dark. I just used YDY 3x2.5mm2. The cable is buried one meter below the ground in white PVC conduit. Since then, he is alive and well. A normal house has arrived on the plot, and the holiday for the whole family in a small garage has gone into oblivion.
There are plans to close the "outhouse" because it blemishes the plot and some people do not use it. It serves as a handy magazine.
When I delete it, I will check the condition of the cable after ten years in the ground. However, please note that I bought a decent conductor with insulation certified for 750V - still from Ożarów. No Chinese food that scares you now in supermarkets and wholesalers and that spreads your fingers.

You have to take into account the possibility that the conduit may be damaged, for example, by a stone that just happened to stumble over the conduit and the ground was still compacted. Moisture could begin to accumulate there (depending on the terrain - water), you know what to do with this cable.

I once saw something like that in a fairly wet area, a really old 110 cable that went to the GPZ. Finally it was damaged and it was necessary to make two couplings but the wires were soaked and rusty.
By the way

ps2.
basically, sometimes the cables themselves also meet it, so you should sprinkle a layer of sand when doing something like this

This is what the cables are for, so that they are directly buried in the ground - don't worry! The conduit and the tube are used for a completely different purpose. As a colleague previously noticed, water will collect in the conduit.

Yes, bury the YDY - it will also hold, but is it professional? Madrik, I also have YDA buried on the plot and it has been operating for 15 years (as "almost" WLZ), but I would never do something like that for a client.

Me neither. I was doing this guide back in the days of my apprenticeship, when I was naive and low-skilled. Today I would eat a spade sooner than I did. And as for cables, not too long ago I found one that, after cutting the insulation, spilled about 5 liters of water under the muff (short circuit inside the cable) ... But it got a short circuit on the old muff.

Recently, I have been digging up a piece of the foundation in the place where I have the power supply for the YDY4x4 utility, and after 12 years there is no trace of it, it has not even changed its color, so no worries .. it's important to sprinkle it with yellow sand so that it does not lie in damp clay

In my humble opinion, the quality of the cable is decisive. The old ones, for example Ożarowskie, were wires ... And today, we have some Chinese wonders at attractive prices with a low insulation Un, cross-section conventionally keeping the size (somehow never for the benefit of the customer) and which can be turned from the insulation without the use of tools ... I saw, for example, such lighting of the alley, made of YDYp 3x1.5mm2, which was tearing in my hands like a fishing line (of the weaker ones).

Madrik wrote:

In my humble opinion, the quality of the cable is decisive. The old ones, for example Ożarowskie, were wires ... And today, we have some Chinese wonders at attractive prices with a low insulation Un, cross-section conventionally keeping the size (somehow never for the benefit of the customer) and which can be turned from the insulation without the use of tools ... I saw, for example, such lighting of the alley, made of YDYp 3x1.5mm2, which was tearing in my hands like a fishing line (of the weaker ones).

What is right is right, the fire cables were unbreakable. There is a tear in the eye that they led to bankruptcy of the prospering factory. It is only possible in our country.

Recently, I was forced to buy cables quickly and drove to the nearest store (known big chain). I bought it, but YDY 3x2.5mm looked like a half-shaft. I am curious how YDY 3x1mm2 looks like - probably like 0.75