In pipeline design, when specifying materials, should a value of 0.5mm be added to fittings?
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I heard that when specifying materials in piping design, an additional 0.5mm is usually added for fittings. Why is that? Is the thickness of fittings 0.5mm greater than that of pipes of the same specification?
The actual thickness of fittings (especially elbows) is slightly greater than that of straight pipes, but the nominal thickness is the same. It is mainly due to the erosion caused by fluids such as elbows……
Because the flow velocity and direction change when the pipe fittings are altered, erosion is severe. Therefore, the thickness of pipe fittings is generally one grade higher than that of pipelines.
The actual thickness of fittings should be slightly greater than that of straight pipes; in my opinion, this is mainly to account for the erosion of the fittings by the medium.
According to Sinopec’s SH standards regarding fittings, the material, pressure rating, or wall thickness of fittings such as elbows, tees, reducers, and pipe caps should be the same as or comparable to those of the pipes they are connected to. In actual construction, if the wall thickness of the fittings differs from that of the connected pipes, welding becomes difficult, and it is hard to achieve a weld quality that meets the design requirements. As a result, contractors usually grind the fittings so that their wall thickness matches that of the connected pipes. “The thickness of pipe fittings is generally one grade higher than that of the pipelines. I’m not sure which standard to refer to I’m really curious to know
For pipes that are not typically under extremely high temperatures and pressures, it is sufficient to select the pressure rating in accordance with the design standards; there is no need to add an additional 0.5 thickness. All the pipe fittings are standard items; adding 0.5MM may not result in any available options for purchase
The thickness of the pipe fittings should be determined through design calculations, and then rounded up to a standard wall thickness; unless you need a non-standard wall thickness, in which case it still needs to be determined through calculation.
I heard that when specifying materials in piping design, an additional 0.5mm is usually added for fittings. Why is that? Is the thickness of fittings 0.5mm greater than that of pipes of the same specification? The following applies only to stainless steel pipe fittings (carbon steel ones will not be covered here; there are too many types and various processing methods). Let’s first consider different situations: 1. Fittings for welded pipes. Raw materials: Seamless steel pipes generally have a positive weight deviation (sold based on actual weight), while welded steel pipes usually have a negative weight deviation (sold based on theoretical weight). Processing: When manufacturing fittings, the wall thickness is reduced; the extent of this reduction varies as follows: 8% for elbows, 10% for tees, 10% for pipe caps. Elbows and reducers do not experience any reduction in wall thickness. These figures are merely estimates; when making actual selections, factors such as wall thickness and the size difference between pipe sections need to be taken into account. The processing tolerance allows for -12.5% in accordance with US standards, European standards, and national standards. Therefore, when selecting pipe materials in practice, choosing a material with a thickness of 0.5 has some basis, but it is not absolutely correct. Especially for fittings using welded steel pipes, the quality of pipes produced by small factories generally falls at the lower end of the range. Recommendation: When purchasing pipe fittings in large quantities, it is advisable for the pipe fitting manufacturer to provide the necessary information. 2. For pipe fittings made from sheets of metal, the raw material – steel plates – usually comes with a negative tolerance; in China, purchases are made based on the theoretical weight, while abroad, the situation is slightly better. During processing, the thickness of these sheet-metal pipe fittings is reduced, with the following reduction rates: 2% for elbows, 4% for tees, 8% for pipe caps; there is no thickness reduction for reducers. The processing tolerance allows for -12.5% in accordance with US standards, European standards, and national standards. Therefore, when selecting the material board in practice, there is no need to consider adding a margin. Additionally, there are also thick-walled fittings (with a wall thickness of over 80S), which are different again. I won’t say anything here.
Thickening it is a waste of investment; considering factors such as erosion, it’s all unreasonable
It should be consistent, right? The main purpose is to learn *:loveliness: