I don't think it's a matter of practice. Because the gutter is bent as a whole and does not leak in itself, the possibility of leaking includes:
1) If the common domestic color plate is used, it will be easy to rust for a long time. When using 2mm ~ 3mm steel plate as trench, rust-proof paint is usually used, and galvanizing or hot-dip galvanizing can also be used. Of course, stainless steel is good, but the price is.... BHP's colour plate is good for corrosion protection. If the requirements are strict, stainless steel (1mm) is recommended for inner trench and color plate for outer trench. It seems heavy to use more than 1 mm plate to make a gutter, which is not suitable for light steel. Outer Tiangou does not need to start a slope. Inner Tiangou can start a slope by adjusting the length of the sling with a distance of 500.
2) Water may leak at the junction of the gutter. Generally speaking, this possibility is not very likely, as long as the lap length is enough, sealant uniformity can be avoided. Welding is used for the overlap of the gutter. The disadvantage of this scheme is that the problem of water accumulation caused by the deflection of the trench is difficult to solve. Deflection must exist, unless pre-bending, slope-finding measures can only be taken, and the density of slope-finding materials should be smaller. It is suggested that steel plate with 2.5mm or more should be used to make it! Tiangou can replace eaves purlin and even contact beams! ___________
3) Reverse water in the gutter. This is mainly due to the insufficient design of the size of the gutter, or the blockage of the downspout, which is not related to the practice, and can be prevented by increasing the overflow outlet.
The stainless steel trench needs to be docked on site. Usually, the corrosion of the stainless steel plate starts from the notches and holes, and the ordinary rivets will also be corroded. (Corrosion at the notches of the stainless steel plate is indeed a problem. However, if the substrate is aluminized and zinc plated, there will be a compensation effect of battery reduction, which can better reduce the corrosion problem here. ) In theory, the surface corrosion resistance of color steel plate is better than that of ordinary steel plate, but it is too thin, once rust begins, it will lead to leakage immediately. Ordinary trench is not the case; Party A also agrees with this point on this issue; therefore, when choosing the scheme, it also prefers ordinary steel plate trench (especially when the column spacing is 6m). As for the strength, in the construction, it is also used as the construction channel. It can be seen that the stiffness of the ordinary trench is better than the color plate trench.