What quota is reserved for buried DN20 steel pipe?
If it is reserved for embedded pipe pre buried steel waterproof casing, set of waterproof casing steel production and installation is to set the quota items, if the outdoor installation of welded steel pipe buried steel casing pre quota items, if it is a reserved hole, then there is no need to set the quota items.
It is an embedded sleeve control sub item, if the reserved hole, then there is no need to cover, special subject structure adjustment factor of the cost of the water supply and drainage engineering, water supply and drainage engineering he is buried under the charge.
