This or That

Usage con­di­tions, creep­age, and volt­age class are just a few exam­ples of the para­me­ters that come into play when the right shield­ing for hol­low insu­la­tors is being designed. Var­i­ous shield­ing options are avail­able to suit whichev­er group of para­me­ters is present in an appli­ca­tion. Pre­vi­ous­ly, Rein­hausen Pow­er Com­pos­ites used liq­uid sil­i­cone rub­ber (LSR) shield­ing tech­nol­o­gy at the Regens­burg site.

In mid-2017, how­ev­er, an acqui­si­tion in France intro­duced a new method: the high-tem­per­a­ture vul­can­iz­ing (HTV) extru­sion process. As a result, Rein­hausen Pow­er Com­pos­ites, as a full-range sup­pli­er and reli­able part­ner, offers its cus­tomers solu­tions for any require­ment, with each made to sat­is­fy the very high­est stan­dards of qual­i­ty and safe­ty. Here, we show­case both tech­nolo­gies and high­light the appli­ca­tions for which they are par­tic­u­lar­ly suit­able.

INJECTION MOLDING FOR LARGE-SERIES PRODUCTION

LSR injec­tion tech­nol­o­gy is an injec­tion mold­ing tech­nol­o­gy. It involves first clamp­ing the pre­cur­sor prod­uct, made from glass rein­forced plas­tic (GRP) pip­ing and an alu­minum fit­ting, in a device. Fol­low­ing this, two mold halves encase the assem­bly and the machine then press­es liq­uid sil­i­cone into the mold under high lev­els of tem­per­a­ture and pres­sure. Once the sil­i­cone shield­ing has been cross-linked, the mold is opened and the insu­la­tor can be removed. After that, the next shield­ing can be mold­ed.

The mold halves con­sist of a large num­ber of mold plates. The length of the shield­ing can be adjust­ed by chang­ing the num­bers that are used. The LSR injec­tion method is ide­al for high­ly stan­dard­ized insul ators that are pro­duced at high vol­umes. This means that, in larg­er-series pro­duc­tion in par­tic­u­lar, there are cost advan­tages to be gained from it. Because it is rel­a­tive­ly expen­sive to pur­chase an indi­vid­ual mold, the method is less suit­able for small­er batch sizes.

EXTRUSION FOR CUSTOM REQUIREMENTS

In the HTV extru­sion process, an extrud­er applies sil­i­cone, which has the con­sis­ten­cy of plas­ticine, to the pre­cur­sor prod­uct. The pre­cur­sor prod­uct then moves about its own axis as well as in the direc­tion of the lon­gi­tu­di­nal axis, cre­at­ing spi­ral-shaped shield­ing on the GRP pipe. A mold plate on the extrud­er deter­mines the geom­e­try that the shield­ing will have. This allows even the most com­pli­cat­ed shield­ing pro­files to be cre­at­ed.

A key char­ac­ter­is­tic of HTV extru­sion tech­nol­o­gy is its high flex­i­bil­i­ty, which makes it ide­al for cre­at­ing cus­tom shield­ing pro­files. Because the mold plates are rel­a­tive­ly inex­pen­sive to man­u­fac­ture, cus­tomers can choose a shield­ing pro­file that meets their exact needs. Spe­cial shield­ing pro­files, such as those with drip edges for ultra-high-volt­age DC appli­ca­tions, can only be man­u­fac­tured using this method.