At the ridge of the roof, the outer plate of the roof can fold up the chassis between the end ribs of the steel plate with the edge closing tool. It is used at the upper end of all roof steel plates with a slope of less than 1 / 2 (250) to ensure that water blown by the wind under the flashing or cover plate will not flow into the building. The operation of edge closing can be carried out before the positioning of the steel plate or after the installation of the steel plate, but the latter method should leave enough clearance (about 50 mm) at the top of the steel plate to facilitate the operation of the edge closing tool. The specific operation method is: place the edge closing tool on the steel plate terminal chassis, slide the tool on the steel plate as soon as possible, and the more inside, the better. Hold the steel plate terminal with a tool, and fold up the chassis, which is about 800. Bend each chassis as described above. When the plate is used in the roof with a slope of less than 1 / 5 (100), the end of the chassis at the lower end of the steel plate shall be slightly bent down (in a lip shape), which can be realized by the same edge collecting tool, so as to ensure that the rainwater is discharged along the end of the steel plate, and will not flow back to the bottom of the flat bottom plate due to the capillary or wind force.
The operation of folding down the edge must be carried out after the roof steel plate is fixed, otherwise the operation will be hindered. When the edge end of the lower folding plate is open properly, clamp the tool on the chassis end and push it inward as far as possible. The tool is close to the end of the chassis, and the handle is shaken about 200 at the same time, so that a downward folding edge is formed at the end of the steel plate.
For very long roof steel plates, expansion joints shall be set, and the distance shall not be greater than the data listed in the table below, so as to overcome the longitudinal thermal displacement. For the penetration fixed type, only one penetration fixed lap can be set between two expansion nodes.
In general, of all the metals used for roof and wall panels, the expansion and contraction of steel is by far the lowest.
In fact, the expansion or contraction displacement between the end of the steel plate and the final support is only a small part of the data shown in the table, because the fixed displacement of the steel plate tends to each end of the steel plate from the center. The displacement at each end is only half of the expansion or contraction. There are also some temperature change displacements in the building structure or roof frame. Although it is not as large as the roof, it still reduces the displacement between the roof panel and its supporting surface. Finally, the differential displacement is further reduced due to the buckling of purlins, especially in the midspan.
The contour plates have corresponding molding foam sealing strips. When they are embedded between the eave support surface and the lower edge of the roof panel (used as eave seal), this bottom seal can prevent dust, insects, birds, rodents and rainwater from entering the rib space.
Along the bottom of the flashing and the cover plate, a molding strip with a contour at the top can be embedded between the bottom of the flashing and the top surface of the roof panel, and properly fixed with double-sided adhesive tape, so as to play a similar sealing role. This is very important. If we don't handle it like this, it will cause water leakage in the house.