Terasest küttetorustikud tee muldkehas

Küttetorustikel teede muldkehas on üsna väike osakaal arvestades kõiki tehnovõrke kokku. Kuid seoses nende paigaldamise komplitseeritusega ja torustiku iseärasustega on küttetorustiku ehitajal vaja teada väga palju nüansse nii toru tehnlise paigalduse kui ka teekatendi ehitamise nõuete kohta. Uute torustike ehitamisel on lisaks normidele ja juhenditele kõige tähtsam kastutatavat materjali mitte kahjustada valede töövõtetega. Näiteks liivaluse puudumine, paisumisvarupatjade valesti paigaldamine, tagasitäitel tehtavad vead. Torustikud on kavandatud kasutamiseks 30 aastat. Vead paigaldusel võivad kahandada toru eluiga märgatavalt ning lisaks kahjustada tee konstruktsiooni ebaühtlaste vajumitega, uhetega. Tee muldkeha ehitamise osas ei ole uute eelisoleeritud torustike ehitamisel arvestatud paigaldatavaid paisumisvarupatju, mis võivad suurtel soojusmagistraalidel ruumala suhtes tee muldkehas väga suured olla. Kuid kuna padjad on väga pehmed ja elastsed, peab olema juhendid nende katmiseks teede muldkehas nt betoonplaatidega. Vanad betoonkünades asuvad küttetorustikud on linna infrastruktuuri üldpilti vaadates väga suure riski allikas. Künade vahed tekitavad pinnaseuhteid ja vanad betoonkonstruktsioonid vahetult teekatendi all võivad mõraneda, praguneda, sisse variseda. Vanade torude asendamine eelisoleeritud torustikega vähendab soojustorustike avariide riske ja kaugkütte võrkude soojuskadusid. Seega on nii kaugkütte tarbijaid, keskkonda kui ka kogu linna tehnovõrku silmas pidades kasulik ja vajalik vanade küttetoru võrkude rekonstrueerimine.

Construction of steel district heating pipes in subgrade under road surfaces. District heating pipes in road subgrade has relatively small proportion of the infrastructure (cables and pipelines) in city environment. However, with regard to the installation of the complexities of the district heating pipes, the builder needs to know a lot of the nuances of the pipe and the installation of the technical side, as well as road construction requirements. In addition to follow the standards and guidelines for constructing the district heating pipelines, it is important not to damage the pipeline with incorrect working techniques. For example, the absence of sand underlayment, improper installation of the extension foam pads, mistakes of sand filling. District heating pipelines are designed for use for 30 years. With improper installation the lifetime of the pipe can be reduced considerably and harm/damage the road surface, subgrade. Regarding the road subgrade, with construction of new district heating pipelines, the extension foam pads can take considerably big volume of the road subgrade. However, because the pillows are very soft and elastic, the road construction standards and manuals have to have some instructions, how to cover these elastic and soft elements in road subgrade, for example with concrete plates. Old type concrete constructions for district heating pipes are a very high-risk source looking at the overall picture of city’s infrastructure. The connections between concrete elements can cause soil draining inside to the elements. This can cause sinkholes and damage the road surface. Replacement of old-type district heating pipes with new pre-insulated pipelines reduces the risk of pipeline accidents and reduces the loss of energy on district heating networks. Thus, both the district heating consumers, the environment and the entire city utility network has advantages when the old-type heating systems are replaced with pre-insulated heating pipes.