Soldering lead pipes with lead

• Publisher: Elsevier Science
• Year: 1913
• Tongue: English
• Weight: 64 KB
• Volume: 175
• Category: Article
• ISSN: 0016-0032
• DOI: 10.1016/s0016-0032(13)90665-7

✦ Synopsis

Fireproofing and Insulation of Wood.

M. DE KEYHEL.

(Rev. Chim. Ind., xxiii, I52.)--This is a discussion of principles, methods, and materials, from which the conclusion is reached that impregnation under pressure is the most efficient method. As a general principle each species of wood requires a different pressure for the necessary penetration, but the pressure remains constant for the same species, regardless of the dimensions of the piece to be impregnated. The penetration of the wood by a crystalloidal liquid is a function of the time. When displacement and penetration take place in a longitudinal sense, irrespective of pressure, the rapidity or duration of the injection will always be in direct relation to the length; for a given length and constant pressure, for the same species, the rapidity may, in certain cases, vary with the initial capillary speed, depending on the concentration of the injected solution. The species generally used are oak, mahogany, teak, ash, beech, gum, walnut, poplar, fir, pitch pine, pine, and birch. The double phosphate of zinc and ammonia obtained by dissolving zinc hydroxide in ammonium hydroxide, and adding phosphoric acid, is superior to any other salt for impregnation, and is the only one that can be applied without inconvenience.

The method of making it on a large scale is given.