Abstract: Provided is a flange joining structure having excellent earthquake resistance, for which the joining operation can be performed simply and easily, similar to conventional practice. A flange joining structure provided with a first member having a first annular flange part, a second member having a second annular flange part, and a seal body placed between the first member and the second member, these components being connected and joined together by a bolt and a nut. The seal body has an annular base part formed from a metal plate and an elastic seal part provided integrally to the annular base part, the elastic seal part being provided so as to cover the annular base part, and the elastic seal part of the seal body sealing the space between the first annular flange part and the second annular flange part.

Abstract: A method for stabilizing material physical properties of recyclable bumpers including the steps of: separating coating from raw material obtained by cleaning, fracturing and drying recyclable bumpers to form a recycled matrix; mixing an additive with the recycled matrix; melting and extruding the mixed matrix with an extrusion machine; cutting the molten and extruded matrix to produce pellets; introducing the pellets into a tank of a predetermined capacity; and mixing the pellets in the tank for a predetermined period of time while again delivering the pellets in the tank to an introduction opening of the tank for reintroduction into the tank in parallel with the pellets that are to be newly introduced.