62508 NDT PRICE LIST 2011.indd - NDT Equipment Services Ltd
62508 NDT PRICE LIST 2011.indd - NDT Equipment Services Ltd
62508 NDT PRICE LIST 2011.indd - NDT Equipment Services Ltd
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PLASTIC CASSETTE INFORMATION<br />
Plastic Cassettes<br />
All types of Single-Envelope Plastic Cassettes are of the same design. They consist of a single<br />
envelope, open at one end, through which film and screens are loaded and unloaded. The open<br />
ends of the envelopes fold over, producing an effective light seal. They are then held closed by<br />
means of VELCRO’ nylon fastener.<br />
There is an extra finger-tab at the bottom to assist in holding the cassette to the bench for easier<br />
and quicker unloading. Closure is normally made on the shorter side of a rectangular cassette,<br />
special versions, with the opening on the long side, can be made to order.<br />
STANDARD SINGLE ENVELOPE CASSETTES These are made from 400 micron black PVC<br />
and have become, over the years, the standard cassette for industry. We do not recommend<br />
their use in very cold weather and advise great care in loading and unloading them in sub-zero<br />
temperatures.<br />
REINFORCED SINGLE ENVELOPE CASSETTES These are made from thin, yet strong<br />
PVC/Nylon/PVC laminated material. The nylon reinforcement is in the form of a mesh and<br />
reduces the tendency of the PVC to split at the seams after much use. The PVC laminate retains<br />
its flexibility in cold climates. Reinforced cassettes are therefore more suitable for use at low<br />
temperatures than the standard type.<br />
ONE SEAM SINGLE ENVELOPE CASSETTES These represent the first major advance in<br />
cassette design since the introduction of ‘VELCRO’ fastening. Constructed in rugged nylonreinforced<br />
PVC, they are made to outlast any other type of flexible cassette. They are<br />
constructed without side-seams, there is just one joint on the back of the cassette. This design<br />
overcomes the weakness of other single envelopes that are welded along the sides; there is no<br />
tendency to split.<br />
The Cassettes are made from specially - formulated, heavy-duty, nylon-reinforced PVC. They are<br />
black on the inside for light-tightness and yellow on the outside for easy recognition.<br />
HEAVY DUTY SINGLE ENVELOPE CASSETTES These are made from double-thickness<br />
material consisting of one layer of standard PVC and one layer of the nylon-reinforced material.<br />
This combination produces a cassette capable of withstanding very tough treatment at normal<br />
temperatures.<br />
DOUBLE ENVELOPE CASSETTES These consist of two plain black envelopes without any<br />
means of closure. Film and screens are loaded into the inner envelope, the smaller of the two.<br />
This is then inserted, open end first, into the larger outer envelope. Light – tightness is assured<br />
due to the open end of the inner is up against the closed end of the outer. They are made from<br />
the standard 400 micron material and are clearly marked ‘INTEX BACK’ on both the inner and the<br />
outer envelope for easy identification in the darkroom and out on site.<br />
The main advantage of Double-Envelope Cassettes is that they lie perfectly flat, having no foldover<br />
ends or ‘VELCRO’ fastening.<br />
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