The return oil pipeline of the heat transfer oil furnace is DN200 – is it necessary to change its diameter before it enters the pump?
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The return oil pipeline of the heat transfer oil furnace is DN200 – is it necessary to change its diameter before it enters the pump? What are the main factors to consider when deciding on whether to use a variable-diameter design? I’m not very familiar with the operational conditions and constraints associated with heat transfer oil furnaces; could someone with expertise please share their insights?
The diameter of the pump’s inlet and outlet pipes is determined by the manufacturer, or can be specified at the time of ordering. The diameter of the inlet and outlet connection pipes is determined by the pressure drop in the system’s piping network; it is generally larger than the diameter specified by the manufacturer. In other words, the pump’s inlet and outlet pipes usually have reduced diameters.
Well, I learned * haha. Salutations to the beginners!
There is definitely a change in diameter, and the type of such change depends on the piping arrangement before the pump inlet: inflow from a lower position results in an eccentric change with the top at the same level, inflow from a higher position leads to an eccentric change with the bottom at the same level, while inflow at the same height results in a concentric change in diameter.
Generally, the diameter of heat transfer oil pipes should be one to two sizes larger than those of the inlet and outlet ports of the circulation pump; the specific diameter is determined by the pressure drop in the system’s piping network”
So I would like to ask: the flow rate in the heat transfer oil system should be above 1.5 m/s, which essentially determines the diameter of the main pipeline. However, in many cases, the inlet and outlet diameters of a circulation pump end up being larger than those calculated. How to address this?
From my experience, even after the diameter is changed, the flow velocity in the main pipe is often higher than the 1.5 m/S you mentioned. Also, where did this figure of 1.5 m/S come from? Previously, 1.5 m/s was the minimum flow velocity applicable to convective heating surfaces.
1.5 m/s is a value specified in the standards for organic heat carrier boilers; so are you saying that we should try to increase the flow rate of the heat transfer oil within the system?
I didn’t say that; I just said that your 1.5M figure isn’t reasonable. What you’re referring to are the regulations regarding flow rates in pipes exposed to heat, but there are no such regulations for pipes that aren’t exposed to heat
1.5 m/s is the standard specified for organic heat carrier boilers; in other words, increasing the flow rate of the heat transfer oil within the system as much as possible is beneficial for ensuring its safety. :)