Machine direction yarn stitched triple layer papermaker's forming fabrics

A triple layer papermaker's forming fabric comprising:

• a set of top CMD yarns;
• a set of top MD yarns interwoven exclusively with the top CMD yarns to form at least part of a top fabric layer having a papermaking surface;
• a set of bottom CMD yarns;
• a set of bottom MD yarns interwoven exclusively with the bottom CMD yarns to form at least part of a bottom fabric layer having a machine side surface, the bottom MD yarns forming bottom MD knuckles as they pass below bottom CMD yarns;
• and
• a pair of additional MD yarns disposed on either side of each top MD yarn, wherein the first yarn of each pair of additional MD yarns weaves exclusively in the top fabric layer and the second yarn of each pair of additional MD yarns completes the weave of the first yarn of each pair of additional MD yarns on the papermaking surface and also weaves with the bottom fabric layer beneath a bottom CMD yarn to form a bottom MD stitching yarn knuckle so as to bind the top fabric layer and the bottom fabric layers together;
• wherein each of the additional MD yarns forms knuckles by passing over the top CMD yarns, and wherein the number of knuckles formed by the first yarn of each pair of additional MD yarns differs from the number of knuckles formed by the second yarn of each pair.

A method of making paper, comprising:

• (a) providing a triple layer papermaker's forming fabric comprising:
• a set of top CMD yarns;
• a set of top MD yarns interwoven exclusively with the top CMD yarns to form at least part of a top fabric layer having a papermaking surface;
• a set of bottom CMD yarns;
• a set of bottom MD yarns interwoven exclusively with the bottom CMD yarns to form at least part of a bottom fabric layer having a machine side surface, the bottom MD yarns forming bottom MD knuckles as they pass below bottom CMD yarns;
• and
• a pair of additional MD yarns disposed on either side of each top MD yarn, wherein the first yarn of each pair of additional MD yarns weaves exclusively in the top fabric layer and the second yarn of each pair of additional MD yarns completes the weave of the first yarn of each pair of additional MD yarns on the papermaking surface and also weaves with the bottom fabric layer beneath a bottom CMD yarn to form a bottom MD stitching yarn knuckle so as to bind the top fabric layer and the bottom fabric layers together;
• wherein each bottom stitching yarn knuckle is formed below a bottom CMD yarn under which an adjacent bottom MD yarn forms a bottom MD knuckle,
• (b) applying paper stock to said papermaker's forming fabric;
• and
• (c) removing moisture from said paper stock.

A triple layer papermaker's forming fabric comprising:

• a set of top CMD yarns;
• a set of top MD yarns interwoven exclusively with the top CMD yarns to form at least part of a top fabric layer having a papermaking surface;
• a set of bottom CMD yarns;
• a set of bottom MD yarns interwoven exclusively with the bottom CMD yarns to form at least part of a bottom fabric layer having a machine side surface, the bottom MD yarns forming machine side MD knuckles as they pass below respective bottom CMD yarns;
• and
• a set of stitching MD yarn pairs, wherein at least one of the stitching MD yarns in each stitching MD yarn pair weaves in both the top fabric layer and the bottom fabric layer and wherein the stitching MD yarns in each stitching MD yarn pair are woven such that at locations where the first of the two stitching MD yarns in each stitching MD yarn pair weaves in the top fabric layer the second of the two stitching MD yarns in the stitching MD yarn pair drops below the top fabric layer so that together the two stitching MD yarns in each stitching MD yarn pair complete the weave in the top fabric layer, and wherein at least some of the stitching MD yarns in the stitching MD yarn pairs bind the top fabric layer and the bottom fabric layer together.