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Stainless steel tank manhole manufacturers


Release time:

2019-06-24

The manhole is a safety emergency ventilation device installed on the top of the storage tank. It is usually used in conjunction with fire retardants and mechanical breathing valves. It can not only avoid accidents due to sudden overpressure or vacuum in the tank caused by accidents, but also play a role in safety fire prevention. It is a safety device to protect the storage tank. It is especially suitable for vault atmospheric pressure tank with nitrogen capped storage materials. 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. The manholes are divided into emergency pressure relief manholes, explosion-proof fire-resistant breathing manholes, tank top manholes, tank wall manholes and core manholes. The manhole is generally composed of 304, 31

The manhole is a safety emergency ventilation device installed on the top of the storage tank. It is usually used in conjunction with fire retardants and mechanical breathing valves. It can not only avoid accidents due to sudden overpressure or vacuum in the tank caused by accidents, but also play a role in safety fire prevention. It is a safety device to protect the storage tank. It is especially suitable for vault atmospheric pressure tank with nitrogen capped storage materials. 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.
The manholes are divided into emergency pressure relief manholes, explosion-proof fire-resistant breathing manholes, tank top manholes, tank wall manholes and core manholes.
Manholes are generally made of 304 steel, 316L stainless steel plate or carbon steel.

 

Specializing in the development and production of various raw materials of stainless steel manholes, oval manholes, round manholes, insulation manholes, rectangular manholes, Huludao manholes, pressure manholes and other manholes refer to the opening structures used for personnel to enter and exit equipment for installation, maintenance and safety inspection. It is mainly composed of short cylinder section (or short pipe), flange and manhole cover with handle. From the perspective of safety inspection, the number of manholes required for pressure vessels and their minimum size are shown in "inspection holes". Manhole materials are available in carbon steel and stainless steel. Manholes are divided into normal pressure and pressure manholes according to pressure conditions; manholes are divided into circular, oval and rectangular manholes according to shape, and rectangular manholes are only applicable to normal pressure equipment; manholes are divided into horizontal and vertical manholes according to installation position; manhole cover is fixed by rotating cover and hanging cover; the speed after opening manhole is common and quick opening. The structure and size of manhole are generally standardized and can be selected or designed according to relevant manuals.
Since the manhole is installed on the lowermost body ring of the oil tank, leakage prevention is particularly important. It is required that the joint surface of the two flanges must be straight and free from floating and twisting. Stiffeners and flanges shall be cut as far as possible on the whole plate without splicing. The flange and the cover plate are processed with sealing rings, and special attention should be paid to protection during construction. 3mm thick asbestos rubber gasket for sealing, no crack is allowed. When installing the bolts on the manhole cover plate, evenly apply diagonal force to prevent the deformation of the manhole cover.
Division
1. Divided by communication pipe block capacity
According to the number of pipe section pipe blocks with a width of 360mm and a height of 250mm (standard six-hole pipe block with an inner diameter of 90mm, referred to as standard block) or single-hole pipe block with an inner diameter of 90mm, the manhole can be divided into three categories: large, medium and small. The size of the manhole set by the communication pipeline shall be set according to the long-term capacity of the communication pipeline. Should not only consider the current construction of communication pipeline capacity.
2, the human hole to divide.
The access to the manhole can be divided into straight manhole, three-way manhole, four-way manhole and oblique manhole. See Table 1 for details. Among them, the oblique manhole is divided into 15 °, 30 °, 45 °, 60 °, 75 ° a total of five. The angle of each inclined manhole can be applied within the range of ± 7.5 °.
3. Divided by bearing load capacity of overlying manhole
It can be divided into steam -20 grade and steam -10 grade by the load bearing capacity of the overburden of the human hole.







 

 

Cost: Manhole flange manufacturers have carefully calculated the products of various specifications and models under the condition of fully thinking about the advantages of both supply and demand. While ensuring "high-quality genuine goods raw materials", control production costs, supply and marketing costs and profits, so as to benefit users. Calculation: raw material production cost handling fee (unforeseen) tax freight profit = cost handling: after the manhole flange is satisfied with the requirements of the tender document and treaty, it will handle the incidents not involved or the abrupt changes encountered in the construction, the necessity of over-planning, the delivery of small batch products, etc. Innovation is the life of an enterprise, the source of its competitiveness, and the ultimate goal of learning. We encourage proposals to improve, encourage any whimsy, and protect every original result.
(1) Stainless steel manholes shall be laid below the freezing line of the local soil, and the thickness of the covering soil on the top of the pipe shall be: when buried under non-roadway, it shall not be less than 0.6m; When buried under roadway, it shall not be less than 0. 8m; buried in paddy field, shall not be less than 0.8m.
(2) Stainless steel manholes shall not pass under the site where explosive, flammable materials and corrosive liquids are accumulated, and shall not be laid in the same trench with other pipelines or cables.
(3) The foundation of the stainless steel manhole shall be the original soil layer, and the foundation of any section that may cause uneven settlement of the pipeline shall be treated. Gas pipelines with cast iron pipes should pay special attention to this point.
(4) The buried pipeline shall have a slope of not less than 0.003, and the drain shall be set at the low point of the pipeline. The distance of the drainer should not be greater than 500m. The buried pipeline shall be provided with reinforced or extra-reinforced anticorrosive coating as required. Installation of low and medium pressure drains.
(5) Underground gas pipelines shall generally not be less than the number of 0.003 set slope. When the large and small pipe diameters are connected or the small pipe branches from the large pipe, it is generally concentric and inclined to the large pipe; If it is not possible to slope to the large pipe, the bottom of the pipe should be aligned and connected, and the low point of the pipe slope should be equipped with a drainage port.
(6) Casing shall be added when the gas pipeline enters the room in humid areas.





 

 

The capacity of vertical oil tank is 5000 msup3,; 1~2 manholes are set below, 5000 msup3, and 2 manholes are set above. The installation of manholes should be separated from the oil inlet and outlet pipelines by no more than 90 °. When only one hole is provided, it should be placed on the opposite side of the light-transmitting hole on the top of the tank; when 2 holes are provided, one of them should be located on the opposite side of the light-transmitting hole, and the other should be at least the first hole phase. Vertical hanging cover stainless steel manhole type, basic parameters, size, technical requirements and relevant use regulations. This standard is applicable to nominal pressure, and, working temperature is greater than -20~100 ℃, heating and depressurization can be applied to vertical hanging cover stainless steel manholes with working temperature of 300 ℃. Our enterprise refuses to excuse, in such a rapidly developing era, "slow" is tantamount to "waiting for death", so what are we not waiting for? Our enterprise to ensure that do not falsify, not opportunistic and not cut corners, this is the three insurmountable "cordon", is the basic requirements of the enterprise staff conduct mouth, is an important standard of "character", is an important concept of "integrity.
Manhole is a commonly used structure on chemical equipment. It is generally set for the installation of equipment mole or the requirements of internal maintenance of equipment for operators to enter and exit. For the selection of manhole, straight hanging cover manhole is generally selected, which is mainly composed of barrel section, flange, flange plate and rotating arm. When opening the manhole, the manhole cover should be turned to the outside by a certain angle. When closing the manhole, it should be turned to the inside, there are complex shortcomings in structure, inconvenient operation, high cost, difficult to assemble, and correspondingly low production efficiency.
Matters needing attention in maintenance and repair of manhole device: manhole is located in the lower part of oil tank, manhole receives great liquid pressure. In order to avoid leakage, it is necessary to strictly require the quality of manhole device. The flange and the cover plate are processed with a sealed water line. Pay attention to maintenance during construction to avoid oil leakage during use. Every time the manhole is removed, it should be marked to avoid dislocation during reinstallation and affect the tightness. When the nuts on the manhole cover plate are to be mounted, the force shall be evenly applied in pairs and diagonally to prevent oil leakage caused by deformation or uneven force of the cover plate.