Injection materials for railroad track beds
AssigneesJapanese National Railways, Nippon Oil Co., Ltd.
InventorsYasuo Katoh, Hideo Kakegawa, Shigeyuki Hayashi, Tadakazu Yamashita
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Abstract
In a railroad track bed an injected layer is formed between the railroad ties and the roadbed so as to protect the latter. The injected layer is composed of an injection material injected through openings formed in the tie. The injection material has a viscosity below 30 poise at a temperature not higher than 200.degree. C. before hardening, and when hardened it has a compressive stress at 10% strain of 0.4 to 30kg/cm.sup.2 at a compressive strain rate at 40.degree. C. of 1.5% per minute.
Claims4
An injection material for railroad track bed and having a compressive stress at 10% strain of 0.4-30 Kg/Cm.sup.2 at a compressive strain at 40.degree. C. of 1.5% per minute upon being cured, said injection material consisting of a member selected from (A) a composition of (a) 97-60 wt. % of blown asphalt having a penetration number of 10-30 at 25.degree. C. and (b) 3-40 wt. % of (i) a paraffin wax having a melting point of 35.degree.-200.degree. C. or (ii) a microcrystalline wax having a melting point of 35.degree.-200.degree. C. and/or (iii) a low molecular weight C.sub.2-4 polyolefin having an average molecular weight of 500-8000 and a melt flow index of 0.1-100,000;
- and (B) a blend of (c) 99-80 wt. % of said composition (A) with (d) 1-20 wt. % of an ethylene-vinyl acetate copolymer having a melt flow index of 0.1-400 and a vinyl acetate content of 5-35 wt. % based on the total amount of the copolymer.
Dependencies are inferred from the claim text.