TRENCHLESS  PIPELINE  REPLACEMENT

MNB equipment has the traction force by 125 t (depending on the machine type), what makes it possible to replace pipelines from 100 mm to 600 mm at the distance by 200 running meters.

The trenchless replacement of a pipeline may be carried out from a pit to a pit (MNB-30, MNB-50, MNB-125), and if necessary, due to especially constrained conditions, from a well or formworks OR-1.5 to a well (MNB-50).

The worn-out pipeline id broken underground and is compacted into the soil.

The material of the pipeline to be replaced:  steel, cast iron, reinforced concrete, ceramics, asbestos sheet.

The material of a new pipeline:  polyethylene.

 

Advantages of the trenchless method of pipelines replacement:

- The risk of damaging the adjacent services is excluded.
- Construction is performed without obstacles for municipal public transport and city residents.
- Increased pipelines capacity.

 

TECHNOLOGICAL  SEQUENCE  OF  PIPELINE  REPLACEMENT
during operation from a pit to a pit
 

	Preliminary works: 2 pits are worked out (working and receiving ones) by the old pipeline axis. The receiving pit size depends on the new pipeline diameter. Under action of MNB or UNB power unit rods are pushed along the old channel for the length of the straight section (by 150-200 m).
	A respective blade is mounted to the preliminarily welded (by means of contact butt welding) polyethylene pipe, which is connected with rods of the unit. The power unit pulls rods along with demolition of the old pipeline and installation of the new polyethylene pipe.

 

If the work is performed from a pit to a pit or from OR-1.5 formworks to a well, polyethylene pipe threaded blanks instead of a polyethylene lash-welded pipe (the blank length – about 0.7 m).