Foreign requirements for portal scaffolding
There are many sizes of portal scaffolds in various countries in the world, and there are two measurement units in the international unit and the British system. For example, the width of the 1219 gantry in English units is 4′ (1219mm) and the height is 6′4” (1930mm), and the width of the 1219 gantry in the international unit is 1200 mm and the height is 1900 mm. Foreign scaffolding companies’ There are four main door frame widths: 900, 914, 1200, 1219 mm, and the door frame height has many dimensions, forming a self-contained system.
The product specifications of several consumer factories in my country are also very different. Some imitate the specifications of foreign products, and some domestic research institutes have designed a system of their own. For example, the width of the door frame is 1219mm in British system, the international unit system is 1200mm, and the frame distance is 1829mm and 1830mm, respectively. Because of these different sizes, the door frames cannot be used interchangeably. For example, there are more than eight kinds of height specifications of the door frame, and there are also many kinds of spacing between the connecting pins, resulting in a wide variety of cross-bracing specifications.
The material and size of steel pipe materials used for door-type scaffolding abroad have special rules. For example, the material used for the main components of the door-type scaffolding in Japan is STK-51 steel, the size is 42.7×2.5mm, and the material used for auxiliary rods It is STK-41 steel, the size is ?34.2×2.3mm and ?27.2×2.0 mm. There is no steel pipe specially used for portal scaffolding in our country. The steel pipe specifications and dimensions requested by the research unit are often not available, resulting in some Manufacturers were forced to use water gas pipes with larger arms. In this way, the steel pipe diameters and wall thicknesses used by various factories are very different (see Table 5), so that even if the outer dimensions of the mast are different, the masts of each plant are still not universal due to the different cross-sectional dimensions of the steel pipes. In addition, due to the use of thick-walled steel pipes, the amount of steel used for portal scaffolding is increased.