22.06.2013 Views

Pocket Guide to Flan..

Pocket Guide to Flan..

Pocket Guide to Flan..

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

The KnolDp Polly-Spt'~re through the Outer .~<br />

COnSists of 0 horcI yet flex- oliow l::~ssure eq~<br />

tble polyurethone outer tK~n between hne I<br />

sphere with o high density and It~t of tt~e Sl~<br />

pOlyuretr~one loom core core. 11~us no inflot<br />

A ser,es of holes drilled required<br />

ex,ble but hard polyurethane outer sphere<br />

Fioure 7-6. Polly-Sphere pig. (Courtesy of Knapp Polly Pig, Inc.)<br />

criss-cross design imparts greater cleaning power,<br />

strength, and wearability. The nose is completely cov-<br />

ered <strong>to</strong> insure proper sealing. For extra-<strong>to</strong>ugh cleaning<br />

jobs, a coat of silicon carbide or abrasives can be added.<br />

Flame-hardened steel wires are bonded <strong>to</strong> the polyure-<br />

thane body of the pig (Figure 7-7) for use on long runs.<br />

The bristles are mounted at the specific angle that<br />

makes them self-sharpening. A simpler pig, the foam<br />

Sweege Pig, is made of extremely soft foam and is de-<br />

signed for temporary sweeping of lines <strong>to</strong> eliminate<br />

things such as oxides which cause red water. They are<br />

propelled by normal water pressure. A Polly-Pig of this<br />

type is shown in Figure 7-8.<br />

141

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!