Introduction and use of manhole:
is installed in a variety of stainless steel tanks, as a passageway and vent for staff during installation, repair, cleaning and maintenance! Generally, stainless steel manholes are made of steel plates of 304 and 316 materials as raw materials, and can also be made according to customer requirements. One manhole should be located near the right side of the oil inlet and outlet pipes, and try to make the manhole face the closed door of the tank chamber so as to facilitate the entry and exit of the oil tank and the ventilation pipe. Since the manhole is installed on the bottom ring of the oil tank, leakage prevention is particularly important. It is required that the joint surface of the two flanges must be flat and free of twisting. Reinforcing plates and flanges should be cut on the whole steel plate without splicing. The flange and cover plate are processed with sealing rings, so special attention should be paid to protection during construction. 3mm thick asbestos rubber gasket is used for sealing, no cracks are allowed. When installing the manhole cover plate to tighten the bolts, force diagonally to prevent the manhole cover from deforming.
HG/T21515-2005 normal pressure manhole application scope: HG/T21515-2005 standard normal pressure manhole is suitable for normal pressure manhole with non-impact working pressure less than 0.07MPA and working temperature 0-250 degrees
Manholes can be divided into straight-through manholes, three-way manholes, four-way manholes, and oblique-through manholes. For details, see Table 1 below. Among them, the oblique manhole is divided into five types: 15°, 30°, 45°, 60°, and 75°. The angle of each oblique manhole can be applied within the range of ±7.5°.