Applications
In the section for New Users, there is a simple, idealised account of a splice of the simplest kind. The picture becomes much more complex when staple yarn is being spliced.
Staple yarn comes in a multiplicity of forms: the staple length may be short or long; the spinning system may take one of many forms; the twist level can take almost any value; the yarn may be singles, two-fold, or multi-fold, with almost any level of folding twist; the yarn may be assembled from one or many fibre types.
The splicing process acts at the level of the individual fibres. It is therefore clear that the splicing of spun yarns, though conforming in general terms to the simple account, must be more difficult. Much of the development effort required to make pneumatic splicing more universal in its application has gone into the generation of specific solutions for staple yarns. With spun yarns, with their more complex construction, it is necessary to present the yarns to the splicing chamber in a form which facilitates the splicing action. To this end, some splicer manufacturers have developed end-preparation techniques, which subject the fibres to a preliminary treatment. Others have used novel chamber forms. Others, including Pentwyn and GTW Developments Ltd., have modified the splicing process itself.
As a general rule, the appearance of splices made in staple yarns is rather less compact than those made in continuous filament yarns. If the yarn construction is particularly difficult, the splices may be fully acceptable in terms of mechanical properties, but may have fluffy "tails".
Finally, it is necessary to consider a special class of continuous filament yarns - those with a number of plies, with a very high level of folding twist, generally used as tyre cords. Such yarns need to be de-twisted, then spliced, then twisted back again. A special splicer is needed for this application.
We suggest that you consult GTW Developments Ltd., or your nearest representative, before deciding on the specific splicer model you wish to purchase.
Further information can be found on the following pages:
· Carpet yarn splicing
· Continuous filament synthetic yarn
· Synthetic staple yarns
· Natural staple yarns
· Heavy yarns/tows
· Fine glass
· Carbon fibre
· High-performance synthetics – such as aramid, Nomex, Dyneema.