The following table gives the lay flat width of polyethylene sleeving required
for nominal pipe sizes.
|
Nominal Pipe Size mm
|
Lay Flat Width
mm
|
|
100
|
350
|
|
150
|
425
|
|
200
|
525
|
|
225
|
635
|
|
250
|
635
|
|
300
|
725
|
|
375
|
875
|
|
450
|
1100
|
|
500
|
1100
|
|
600
|
1270
|
|
 |
TO AS3680
POLYETHYLENE SLEEVING FOR THE PROTECTION OF DUCTILE AND COPPER PIPELINES
APPLICATION OF LOOSE
POLYETHYLENE SLEEVING
Ductile Iron pipes and fittings are normally coated with bituminous
paint. The inherent corrosion resistance of the ductile iron pipe and fittings with standard coating provides adequate
protection except in aggressive soils where additional protection in the form of loose polyethylene sleeving is
required.
Loose polyethylene sleeving is a heavy duty polyethylene sheet manufactured in tubular form to facilitate its application
to pipes. The tube of polyethylene sheeting is provided in rolls of varying lengths dependent on the folded flat
width of the tube (lay flat width).
The sleeving is easily applied on site and thus precludes the risk of damage during transportation.
The object of the sleeving is to form a continuous uniform environment along the length of the pipeline to be protected.
The sleeving is not intended to be a completely air and water tight protection, but care should be taken to prevent
any material becoming lodged between the pipe and the encasement during laying and jointing. Damage to the sleeving
should be avoided during trench backfilling and compaction operations. |