Which standard does the pipe welding Dyne factor come from?

The standard unit of measurement used in the international engineering community to quantify welding workload.

Welding dyne factor: DIN (Diameter-Inch). The welding dyne factor is a unit used to calculate the amount of work required for welding, that is, the welding equivalent. Abroad it is called a dyne; one weld with a diameter of 1 inch corresponds to 1 welding equivalent (1 dyne). Ten 1-inch welds equal 10 dynes, and two 5-inch welds also equal 10 dynes. This method of calculation takes into account only the diameter of the welds and does not consider the influence of wall thickness, so it is only applicable to welds with a wall thickness of 8 millimeters or less. For values over 8 mm, a coefficient of 0.1 is added for every additional 2 mm. Specifically, the coefficients can also be debated. For the plant area, the welding workload can be calculated using an empirical formula: Welding workload in the plant area = Total pipeline length × 0.127 (correction factor) × Pipeline diameter + (Number of elbows × Pipeline diameter × 2) + (Number of tees × Pipeline diameter × 3) + (Number of flanges × Pipeline diameter) + (Number of reducers × Pipeline diameter × 2). For areas that are not part of the plant, i.e., pipe trunks, the calculation can be done using the following formula: Welding workload in non-plant areas = Number of welds (Total pipeline length/Length of each individual pipeline) × Pipeline diameter + (Number of elbows × Pipeline diameter × 2) + (Number of tees × Pipeline diameter × 3) + (Number of flanges × Pipeline diameter) + (Number of reducers × Pipeline diameter × 2). For example, if the pipeline diameter is 3”, and there are 20 welds, then the welding workload is 60”. The \"pipe diameter\" in the above formula refers to the outer diameter of the pipe in imperial units. The formula provided is merely a calculation method for pipes of one specific diameter; all pipes, regardless of their diameter, are calculated using this same formula. By adding up the results obtained from these calculations, the total amount of work required for welding can be determined. For thick-walled pipes, a coefficient can be multiplied based on experience. There is another method: based on experience, the total number of welds can be estimated from the number of drawings in the overall layout diagram. Per port D: N25,1 dynes ； DN50,2 dynes ； DN80, 3 dynes ； DN100, 4 dynes ； DN125,5 dynes ； DN150, 6 dynes ； DN200, 8 dynes ； DN250, 10 dynes ； DN300, 12 dynes ； DN350, 14 dynes ； DN400, 16 dynes ； DN450, 18 dynes ；

Search for “welding equivalent”, which includes wall thickness correction. It is also related to the welding procedure specifications (wall thickness, diameter of the wire/elektrode used, number of welding layers)

Brother has covered everything very thoroughly, but is there a source for it? It didn’t answer my questions

Was there any documentation supporting the \"extended meter\" as a measure of welding workload in the domestic engineering industry in the past?

There really isn’t one; 1DIN is 25.4