Structural sandwich plate members

1. A structural sandwich plate member comprising: a first outer metal plate including a left side plate and a right side plate and a second outer metal plate; an unfoamed polyurethane elastomer core bonded to said outer metal plates with sufficient strength to transfer shear forces therebetween; and a rolled or extruded edge member fitted between and connected to said first and second outer metal plates and extending along at least a part of the periphery of said outer metal plates and said profile providing a weld location suitable for welding said structural sandwich plate member to another structural sandwich plate member, said edge member comprising: a web extending perpendicularly to said first and second outer metal plates and having a first end and a second end, and a first flange disposed intermediate the first and second ends, the second end being welded to said second outer metal plate, the web extending from said second end to said first flange in contact with said polyurethane elastomer core, wherein the first flange is substantially parallel to said first outer metal plate in contact with said polyurethane elastomer core and welded to surfaces of said left side plate and said right side plate of said first outer metal plate that face the second outer metal plate, the web extending from said first flange in a direction away from said polyurethane elastomer core and perpendicularly to said first metal plate beyond said first flange and said first and second outer metal plates to said first end.

2. A structural sandwich plate member according to claim 1 wherein said edge member comprises: a second flange extending parallel to said first flange from said second end of said web and at least partially lying against said second outer plate.

3. A structural sandwich plate member according to claim 2 wherein said web is upstanding from one edge of said first flange.

4. A structural sandwich plate member according to claim 3 wherein said edge member further comprises a third flange substantially parallel to said first flange and projecting from said web in the opposite direction to said first flange, said third flange being positioned to act as a backing bar for welding said first outer plate to said edge member.

5. A structural sandwich plate member according to claim 2 wherein at least one edge of said first flange is provided with preparations for butt welding to another flange or plate.

6. A structural sandwich plate member according to claim 2 wherein said second flange extends beyond the edge of said second outer plate to act as a support for welding another plate or flange to said structural sandwich plate member.

7. A structural part comprising at least first and second structural sandwich plate members,

said first structural sandwich plate member including a first outer plate including a left side plate and a right side plate and a second outer metal plate, an unfoamed polyurethane elastomer core bonded to said outer metal plates with sufficient strength to transfer shear forces therebetween, and a rolled or extruded edge member fitted between and connected to said first and second outer metal plates and extending along at least a part of the periphery of said outer metal plates, and said edge member providing a weld location suitable for welding said structural sandwich plate member to another structural sandwich plate member, said edge member comprising a web extending perpendicularly to said first and second outer metal plates and having a first end and a second end, and a first flange disposed intermediate the first and second ends, the second end being welded to said second outer metal plate, the web extending from said second end to said first flange in contact with said polyurethane elastomer core, wherein the first flange is substantially parallel to said first outer metal plate in contact with said polyurethane elastomer core and welded to surfaces of said left side plate and said right side plate of said first outer metal plate that face the second outer metal plate, the web extending from said first flange in a direction away from said polyurethane elastomer core and perpendicularly to said first metal plate beyond said first flange and said first and second outer metal plate to said first end,

said second structural sandwich plate member comprising first and second outer metal plates and an elastomeric core bonded to said outer metal plates with sufficient strength to transfer shear forces therebetween, and

said first and second structural sandwich plate members being joined together by welding along said edge member.