Manhole, the sewer, for people in and out of repair can hole in and out of line, boiler, drain, or similar facilities.
A hole with cover, people can from this hole in and out of line, boiler, drain, or similar facilities.Manhole is installed on top of the tank safety emergency ventilation device, usually with flame damper, using mechanical breather valve, can avoid the accident caused sharp overpressure or vacuum in tank and tank damage and accident, security fire effect, is to protect the safety of tank device, especially suitable for the storage of materials with nitrogen gas cap vault atmospheric tank.Emissions with constant pressure and constant pressure suction, flexible open and close, fire safety, compact structure, good sealing performance, safe and reliable.
The division of types of manhole
1, communication pipe piece capacity
According to specification for wide manhole can accommodate 360 mm and 250 mm high (standard bore six tube diameter 90 mm cement pipe piece, hereinafter referred to as the standard block) of the pipe cross section pipe or single span pipeline in the number of hole diameter 90 mm, divided into three categories large, medium and small
2, manhole to divide
With manhole to division can be divided into direct manhole manhole, tee, four-way manhole and manhole, specific details.Among them, the oblique tong manhole is divided into 15 °, 30 °, 45 °, 60 °, 75 °, a total of five.Each of the inclined Angle of manhole can be applied to within + / - 7.5 °.
3, to the manhole overlying the load capability
With manhole overlying the load capability can be divided into steam - 20 level and steam - 10 level two