1. Metal roof construction process
Construction preparation → structural review and measurement → installation of purlin pallets → installation of channel steel purlins → installation of roof bottom plates → installation of fixed supports → installation of roof panels → roof edge trimming and flashing treatment → roof cleaning → completion.
2. Installation of profiled steel base plate
According to the requirements of the design drawings, measure and review the length and amount of the bottom plate in the installation area at the construction site → The factory performs profiling based on the actual measured length and size of the bottom plate and the number of processed pieces and then transports it to the construction site. The profiled steel plates are installed from bottom to top along the vertical direction of the purlins. The profiled steel plate is fixedly connected to the steel frame purlins using self-tapping nails with rubber rings. The profiled steel plate is along the longitudinal direction. Before installation, it is necessary to lay out the materials according to the drawing, and mark the plate area as the roof profiled bottom plate of this project. In order to reversely lift the bottom plate, a straight-arm aerial vehicle is used during construction to ensure construction safety.
3. T-code installation
The panel T code is the support member of the roof panel. It is the stressed component that transmits the roof load to the purlins. Its installation quality directly affects the wind resistance performance of the roof panel. The installation error of the panel T code will also affect the quality of the aluminum alloy roof panel. Vertical free expansion and appearance of the roof panels, therefore, the installation of the T-code of the panels is a key process of this project. During construction, it is important to control the horizontal position deviation, tilt angle and plane angle of the support.
Plane position
If the horizontal position deviation of the support exceeds 5 mm (that is, the support is not in a straight line longitudinally with other supports), it will inevitably affect the free expansion and contraction of the plate in the longitudinal direction. When the plate expands due to heat, excessive resistance may occur at the deviation support. The bottom bulges, or the plate ribs are damaged due to long-term friction, causing water leakage.
The inclination angle of the support in the vertical plane
When the inclination angle of the support on the vertical plane is greater than 2°, the plate ribs will bite the plate ribs when biting, causing water leakage. When the inclination angle of the support is greater than 1°, a gap greater than 1.05 mm will occur within the range of the support (60 mm). The height difference will cause friction when the board expands and contracts, and under long-term action, the board ribs will be worn out and cause water leakage.
The support turns in the horizontal plane
The twisting angle of the bearing on the horizontal plane is a common problem that easily occurs when installing the bearing. The main reason is that when tightening the fixing screws, the bearing is not pressed tightly or the scale gap is too large. The bearing rotates under the action of torsion force. The construction workers were irresponsible and did not correct it later. This deviation will also cause friction between the plate ribs and cause water leakage. In addition, if an error in the elevation is found during the installation of the supports, the purlins must still be adjusted to ensure that the supports meet the installation requirements.
Panel T-code installation mainly involves the following construction steps:
a. Laying out the lines: First, use a total station to measure and lay out the board end contours at both ends of each section of the board, and then measure the design partition lines. When laying out the T code, in order to facilitate construction, a baseline can be popped up on the roof first as the longitudinal control line for the T code installation on the panel. The other T code laying out lines adopt the principle of equalization, that is, the upper and lower arcs of the board are evenly divided according to the number of boards. points to determine the position of the two end points of the board, and then determine the position of the middle T code by drawing a line between the two points. If the roof curvature is large and the line cannot be drawn at one time, another row of control T codes can be set in the middle. The position of the panel T codes along the length of the panel only needs to be at the center of the top surface of the purlins. The number of panel T codes determines the wind resistance of the roof panel. Therefore, the number of rows of panel T codes along the panel length is strictly in accordance with the design drawings.
b. Panel T code fixed
The T code on the panel of this project is fixed with self-tapping screws. The self-tapping screws must have anti-aging sealing rings. The rotation speed of the electric drill should be 2000-2500 rpm. Then install the hexagonal sleeve on the electric drill bit and insert the screws. , align the T code of the panel to its installation position, and then drive in a self-tapping screw. During installation, the screw and electric drill must be perpendicular to the upper surface of the purlin. Pull the electric switch and do not stop halfway. Stop drilling quickly after the screw is in place. At this time, the position of the T code on the panel will be slightly offset, and its positioning must be rechecked before the self-tapping screws on the other side can be driven in. (Can control panel T code horizontal angle error). When installing the panel T codes, the heat insulation pad below must be installed at the same time. c. Review the position of the panel T codes and visually check whether the panel T codes in each column are in a straight line. If a panel T code with a large deviation is found, place it in the Roof panels must be corrected before installation until they meet the requirements for panel installation. If there is a large deviation in the T code of the panel and the undercut is installed on the roof panel, it will affect the free expansion and contraction of the roof panel. In severe cases, the panel ribs will be worn out under the repeated action of temperature.
4. Installation of standing seam roof panels
Before panel installation, check the installation quality of the support again to ensure that it meets the panel installation requirements before proceeding with panel installation.
Pay off
After the T-code has been inspected and the installation quality has been strictly controlled, the panel installation positioning line can be placed. Generally, it is based on the surface.
The distance between the slab and the gutter is the control line. The principle for determining the length of the panel out of the gutter is 1/1000 of the panel length + the downward bending length of 15mm + the width of the drip sheet 30mm + the size allowance of 30mm, but not less than 100mm. For example: the length of the roof panel is 30 meters, and the length of the roof panel extending into the gutter is 30+15+30+30=105mm.
Get in position
The construction personnel lift the board to the installation position. When in place, they first control the line at the end of the board, and then press the overlapping edge of the previous board hard. Check whether the overlapping edges can be tightly joined. If not, the problem should be found and dealt with as soon as possible.
undercut
After the panel position is adjusted, install the foam seal under the end panel and then undercut. When undercutting is required, it should be connected
Continuous and smooth, without distortion or cracks. During the advancement of the undercutting machine, the overlapping joint must be made with force within 1m in front of it.
The edges are tightly joined. For this project, the key to the quality of the undercut lies in whether strong force is used to make the overlapping edges tightly connected during the undercut process.
combine. The panels placed in place on the same day must be undercut to ensure that the panels will not be blown away or blown away when the wind comes at night. Panel material thickness is
When the diameter is less than 1 mm, the bite diameter is between 20 and 22 mm, generally 21 mm.
5. Board edge trimming
Trim the edges of the eaves and gutters. After trimming, ensure that the length of the roof panels extending into the gutters is consistent with the designed size. This can effectively prevent rainwater from blowing into the roof interlayer under the action of wind.
6. Installation of cornice drip sheets
Before installing the drip sheet, trim the edge of the board at the cornice and gutter. First, pop up the trim line at the location that needs to be trimmed based on the design size of the edge of the board that needs to extend into the gutter. During trimming, use an automatic edge trimmer to cut along the trim line. , which not only ensures that the length of the roof panel extending into the gutter is consistent with the designed size, but also ensures the beauty of the entire roof appearance after trimming. It can also effectively prevent rainwater from blowing into the roof interlayer under the action of wind. The cornice seal is then installed, and finally the drip sheets are installed, which are fixed with rivets, one steel rivet per rib.
When installing the drip sheets, attention should be paid to the fact that if the board lengths are different, the drip sheets must be disconnected to allow for different expansion and contraction of the boards, leaving a 5mm gap between the drip sheets.
7. Folding
The principle of folding is that where water flows into the gutter, the folding edge should be downward, and the high end of the panel (roof ridge) should be folded upward. Do not use excessive force when folding, use even force, and keep the folding angle consistent.