Tank Top Dn600 Pn1.6 304 Asme Manhole Flange Power Plant Accessories

Product Specification

Power plant accessories special flange manhole, tank top manhole DN600 PN1.6 304 ASME manhole

Manhole refers to the opening structure used for personnel to enter and exit the equipment for installation, maintenance and safety inspection. It is mainly composed of short tube section (or short tube), flange and manhole cover with handle. From the perspective of safety inspection, the number of manholes required for pressure vessels and their minimum dimensions are shown in "Inspection Holes". The manhole materials are carbon steel and stainless steel. Manholes are divided into normal pressure and pressure manholes according to pressure conditions; manholes are divided into round, oval and rectangular manholes according to their shape. Rectangular manholes are only suitable for atmospheric equipment; manholes are divided into horizontal according to the installation position. And vertical installation manhole; the fixing method of manhole cover includes rotating cover and hanging cover; the speed after opening of the manhole has ordinary type and quick opening type, the structure and size of the manhole are generally standardized, please refer to the relevant manual for selection or design.

The manhole is a safety emergency ventilation device installed on the top of the storage tank. It is usually used in conjunction with fire extinguishers and mechanical breathing valves. It can not only avoid accidents caused by sudden overpressure or vacuum in the tank due to accidents, but also damage to the storage tank. It is a safety device to protect the storage tank, and it is a safety device to protect the storage tank. It is especially suitable for the vaulted atmospheric tank with nitrogen topped by the storage material. It has the advantages of constant pressure discharge, constant pressure suction, flexible opening and closing, safe fire resistance, compact structure, good sealing performance, safety and reliability.
Manholes are divided into emergency pressure relief manholes, explosion-proof fire-resistance breathing manholes, tank top manholes, tank wall manholes and cored manholes.
Manholes are generally made of 304, 316L stainless steel plate or carbon steel.

Manholes have been shaped products, usually 600mm in diameter. The center of the manhole is generally 750mm from the floor. It is convenient for the staff to enter and exit the oil tank or ventilate during installation, cleaning and maintenance.
The manhole of the non-metal oil tank is set on the top of the tank, and the manhole of the metal oil tank is set on the bottom plate of the tank wall. Most of them are round holes with a diameter of 600mm, with a center distance of 750mm from the bottom plate, which is used by oil tank cleaning or maintenance personnel to enter and exit the oil tank. It is also called a door. Use manholes for lighting and ventilation at all times during maintenance and cleaning of oil tanks. Vertical oil tanks have 1 to 2 manholes when the capacity is below 5000m3, and 2 manholes for those above 5000m3. The installation of the manhole should be no more than 90° away from the oil inlet and outlet pipelines. When only one manhole is provided, it should be placed on the opposite side of the light-transmitting hole on the top of the tank; when two manholes are provided, one of them is located on the opposite side of the light-transmitting hole, and the other should be separated from the first manhole by at least 90 °.

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, the maintenance 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 to tighten the bolts, force evenly at diagonal angles to prevent the manhole cover from deforming.