Silane

We are planning to make in home compounding for XLPE LV. Can anyone recommend me suppliers for the materials i.e. silane, antioxidant, catalyst, etc.?
Thanks,

Hello Danny,

How are you planning to manufacture your XLPE compound?

(1) Method 1 - Conventional

(a) Manufacture of a Pre-Grafted Polyethylene Compound
This is the process where a base compound is manufactured in a continuous mixing extruder and where vinyl silane is grafted to a polyethylene matrix, mixed with a peroxide initiator, an antioxidant, a UV stabilizer if needed and then pelletized.

Manufacture of a Catalyst Masterbatch
In a second and separate mixing operation, the catalyst masterbatch is produced. This consists of polyethylene compounded with an organo tin catalyst such as di-butyl tin laureate and then pelletized.

(c) Standard Extrusion with Gravimetric Mixing
(a) and (b) are gravimetrically mixed along with a color masterbatch on any standard production thermoplastic extrusion line where low voltage power cable is manufactured.


(2) Method 2 - Dry-Silane Process
This is where all is done at once on one thermoplastic production extrusion line where low voltage power cable is manufactured. To learn more about this process, go to the Rosendahl Maschinen GmbH. (Austria) web site at www.rosendahlaustria.com/ and click on "Products". Then click on " Power Cable | Article". You need Adobe Acrobat Reader to read and download this article. If you are thinking of using this process, you can certainly find out who Rosendahl recommends as the material suppliers.

You can get the latest free download of Adobe Acrobat Reader here. www.adobe.com/products/acrobat/readstep2.html

Sincerely,

Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com

For gravimetric dosing of catalyst masterbatch and even gravimetic dosing of liquid silane check the equipment of INOEX www.INOEX.de

We use it for MV

As we understand it, Inoex specializes in gravimetrics for the direct dosing of liquid silane and organo-peroxide directly into the extruder throat along with a masterbatch catalyst,a color masterbatch and the base polyethylene. This is somewhat akin to the the Monosil process developed by Maillefer for XLPE (without silane) and to some extent the organo-peroxide injection process and equipment sold by Kabel und Draht GmbH (Now Südkabel GmbH at www.suedkabel.de/ ) some twenty-five years ago.

We advise extreme caution to all in this regard re these processes because of the opportunity of explosions and/ or fires with one or more of the liquid components. Proper handling and control of the liquids is fundamental and extremely important.

Instead we much prefer the far safer solid "Ethylene + Vinyl Silane" pellets, the catalyst masterbatch pellets and perhaps the color concentrate pellet masterbatch all gravimetrically mixed with the base polyethylene compound at the extruder throat. If you wish to know more about this, see Borealis ((Visico/ Ambicat) www.borealisgroup.com/public/pdf/52.pdf

Sincerely,

Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com

Hello Peter,

I fully agree with your remarks about liquid silane and Visico being the better solution. With Visico one doesn't have any problems and the machine always runs beautifully. BUT-It's EXPENSIVE and since we have to earn money we have to look at the cost/ price. Cable manufacturing is a difficult business and every dollar is one.

Jan