SYSTEM OF ROD PACKING Russian patent published in 2011 - IPC F16J15/20 

FIELD: machine building.

SUBSTANCE: system of rod packing consists of damping ring, of rod packing and of dust protective packing arranged successively in this order from side of hydraulic fluid to external side in circular gap between two elements at reciprocal motion. The damping ring is made out of thermoplastic polyurethane moulded product produced by processing thermoplastic polyurethane moulded product after reaction between (A) poly-carbonate-diol of high molecular weight with average molecular weight Mn 500-6000, (B) aromatic di-isocyanate and (C) diol of low molecular weight as agent for elongation of chain at ratio of NCO/OH from 0.95 to 1.20, by thermal treatment at temperature (Tg) of vitrification of solid phase to 170°C and above and endothermic peak area (ΔH) at Tg coming to 5 J/g or more by means of differential scanning calorimetry. The damping ring is made out of polyurethane moulded product.

EFFECT: perfect heat resistance of ring withstanding working ambient temperature; characteristics of shrinking correspondingly reacting to eccentricity.

5 cl, 2 dwg