Attention should be paid to freezing prevention in northern sewage treatment projects!
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Recently, the company carried out an EPC project in the north with a total investment of 150 million. During the commissioning and testing phase, a serious problem was identified: many pipes froze and cracked, as did various valves, especially those of the HT200 type. Therefore, when purchasing valves in the future, it is important to choose ones made of WCB material.
HT200 type? What type is it? Is WCB also carbon steel? This material is okay, right?
HT: Gray iron; WCB: Carbon steel. Last edited by li*ch1968 on 2009-4-2 07:51.]
In the north, due to the low temperatures in winter, many materials undergo changes in their properties at such low temperatures, resulting in damage to equipment or components. This is because the impact of weather conditions was not taken into account during design, leading to abnormal operation of the system. Okay, very good.
It is indeed quite troublesome. We usually add a secondary line to ensure that there is a continuous flow of water inside the pipeline
It is indeed a very important issue; firstly, low temperatures directly damage the facilities, and secondly, in microbial treatment, the activity of fungi **decreases**.
There must be issues with the quality of the valves as well; gray cast iron shouldn’t be that fragile. What is the low temperature threshold? Was the pipeline not drained?
Failing to take winter temperatures into account when working on projects in the north is simply a problem on the part of the designers! With the buried pipes buried at an adequate depth and the exposed pipe fittings properly insulated, damage is impossible! This post was last edited by li*ch1968 on 2009-4-2 07:53]
It might be the stress caused by the expansion of water as it freezes, due to limited water flow during culture; any material might not be able to withstand such stress.
Surely insulation was taken into consideration, right? !
In my opinion, when dealing with water treatment in the north, it is necessary to insulate the pipes before water enters them. It is also important to ensure that water keeps flowing through the pipes, or to drain the water from them after they stop operating. Otherwise, if there is stagnant water left in the pipes after they stop working, these pipes or connections can crack due to freezing. This post was last edited by li*ch1968 on 2009-4-2 07:54.]
Putting aside the issue of materials for now, in the winters of the north, facilities such as pipes are prone to damage. Apart from the low-temperature properties of the materials, there is another important reason: the water inside pipes or water pumps freezes. As we all know, ice occupies more volume than water when they have the same mass; if there is water in the pipes or pumps, their surfaces can burst under the pressure. I have encountered this situation before – a pump with a 2 cm thick casing actually burst. To solve this problem, in addition to burying the pipes beneath the frost line, it is essential to ensure proper insulation of the pipes. If no water flows into them, the water inside the pipes must be drained completely.