Layout scale issue
Thread Content
In accordance with the unified regulations on the content and level of detail for construction drawings in chemical process design specified in HG/T 20519-2009, the general scale for equipment layout drawings is 1:100, while the general scale for pipeline layout drawings is 1:50. Yet this guy used a scale of 1:70 for everything, and it was still approved. The reviewer raised objections, to which it was retorted: \"This device is special, so only this ratio can be used.\" Time is running out now; if we request a change in the proportions and redo the slicing, we won’t be able to keep up with the schedule. Besides, is there anything wrong with such a ratio? ”
The ratio is not fixed; the purpose is to be able to see the elements on the drawing clearly.
On the company’s standard drawings, the fonts, labels, and direction indicators are all set according to specific proportions, and he changed them all. Other work sections follow the standards, but his unit is treated specially. What would the owners, constructors, supervisors, and safety inspection agencies think upon seeing such a diagram (which contains GC1 pipes)?
Well then, it’s this guy’s problem. The owner’s supervisor will indeed look for faults; if there’s no reason for it and the explanation doesn’t hold up, it’s better to make changes. So as not to be sent back later.
Here, it is allowed to adjust the ratio according to specific circumstances. Equipment layout drawings are usually drawn at a scale of 1:100, but if the area in question is very small, a 1:100 scale makes it difficult to see details as there is too much empty space; therefore, scales such as 1:30 are allowed. However, the font, tabs, and direction indicators cannot be special; they need to be uniform.
Wasn’t this checked during the design phase and before verification?
The level of verification – better not mention it, haha, you know what I mean.
1:70 is not a commonly used scale; in the era of hand-drawn illustrations, scales were used for drawing, so certain common scales were established, along with corresponding scales. If it is drawn manually at a 1:70 scale, it is unlikely to achieve such a ratio without an appropriate scale. With modern computers, it’s theoretically possible to achieve any scale, but conventional scales such as 1:100 and 1:50 are used, as these allow for the direct measurement of dimensions on a drawing that may not be indicated or have been omitted, using a ruler. To facilitate construction workers.
It’s really crazy to run into something like this; drawing usually follows the company standards. No comments even after verification?
I feel that the scale on the drawings is basically of no use to the construction party. Measuring on the drawings is not as accurate as using a meter in reality; when looking at drawings, the main goal is to know what components are present and where they are located roughly, as well as what precautions need to be taken according to the design specifications. Other details are not given much attention, at least that’s how it is in our instrumentation field. But as for the specific format and such, the design institute should have its own regulations; before the drawings are reviewed, they can’t be considered the final blueprint, right? Generally, no one pays attention to the scale of the drawings; the client is mainly concerned with whether the design is reasonable and whether it follows the requirements specified in the MR document ； The contractor checks whether there is a shortage of materials and verifies that the drawings related to this specialty are consistent with those from other specialties.
My situation is the same as yours; the construction worker said there are errors in the positions of the equipment connections, as well as installation errors. The dimensions shown on the drawings are merely for reference – what matters is how the wires are routed, what size the pipes are, and the positions of the valves and instruments.