Page 268 - Pipeline Pigging Technology

Gels for commissioning and production

design of the gel and the customer is required to ensure that a suitable system
is utilized.

POLYMER GEL PIG

In addition to the cleaning gel systems, Nowsco has developed a viscous
water-soluble pre-moulded pig which is compressible and can be pumped
through various diameters of pipework, and which has been used in place of
conventional pigs as discussed earlier.
The polymer is precast in a steel canister for transportation and loading
into the pig launcher; should the client wish it can be colour coded for ease
of identification.
Nowsco has found that these types of pigs have to be selectively used, and
that in long gas lines breakthrough of gas and destruction of the pig may occur.
They do, however, have applications where outlet restrictions are small as the
pigs can be broken up underpressure and discharged through small-diameter
outlets.

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