Forming fabric of double-layer type

Claim 1

An improved open mesh fabric for use in forming a fiber web in papermaking, cellulose and similar machines, said fabric comprising: a first system of warp threads and a first system of weft threads, all warp threads of said first system of warp threads weaving with the first system of weft threads in a repeating pattern to form a first complete weave which during position of use of said fabric faces said fiber web to be formed thereon; a second system of warp threads and a second system of weft threads, said two second systems of threads interwoven to form a second complete weave; warp threads of said second system of warp threads being arrange in groups, each such group comprising at least two adjacent warp threads interweaving essentially in side by side relation parallel with each other and in a repeating pattern with weft threads of said second system of weft threads; and said first complete weave and said second complete weave being joined together to form a double weave where at least one of the adjacent warp threads, interweaving essentially is side by side relation, parallel with each other, interlaces with weft threads of the first system of weft threads.