Manholes
Manholes and handholes have the function of granting access to a confined space. The only difference between manholes and handholes is the size of the opening: an adult fits through a manhole, whereas only a hand or an arm fits through a handhole. Manholes and handholes are composite items which consist of a manhole ring, a manhole cover, a rubber gasket, bolts and possibly a coaming welded to the manhole ring (depending on the type).
More information
More information about manholes
Manholes and handholes come in many shapes and sizes:
- Materials: steel, stainless steel or aluminium
- Shapes: oval or round
- Types: surface-mounted or flush (in various versions)
- Number of bolts: varying from 22 to a version with only one (central) bolt
- Dimensions: various sizes
The oval manholes are often used. They come in the following types:
Type A: Surface-mounted |
Type B: Surface-mounted with coaming |
Type C: Heavy-duty model with thick cover (flush) |
Type D: Heavy duty model with thin cover (flush) |
The stainless-steel and aluminium manholes are fitted with stainless-steel bolts as standard.
Steel manholes are standard delivered without bolts. Galvanised or stainless-steel bolts can be ordered separately.
Aluminium manhole rings are supplied with stainless-steel thread inserts as standard.
The quality of the materials used is as follows:
- Stainless-steel manholes and handholes: Stainless steel 316
- Aluminium manholes and handholes: 5083-H321
- Stainless-steel bolts: A4
The pictures below give an impression of the working of manholes with one central bolt:
Manhole with one central bolt |
Manhole with one central bolt |
Spanner for manhole with single bolt |
Some components are also available separately.
See the article group ‘Rubber seals’ for the rubber gaskets used for manholes.
