Section Beam

1. A large flanged roll upon which warp yarn is wound at the beam warper in preparation for slashing. 2. Small flanged or unflanged beams assembled side-by-side on the shaft of a warp beam for further processing.

Section Mark

A fabric defect consisting of marks running warpwise in an evenly repeating pattern caused by the improper setting of sections in silk system (or indirect) warping.

Section marks

Individual warp stripes in woven or warp-knitted fabrics that occur at regular intervals across part or all of a fabric width, the distribution coinciding with the width of the warping section, and the stripes being the result of tension or individual package differences within the section during warping.

Section warping

1. Yorkshire and Scotch warping and silk-system warping; horizontal-mill warping. A two stage-machine method of preparing a warp on beam, consisting in:
(i) winding a warp in sections on a reel (drum, mill, swift);
(ii) beaming-off the complete warp from the reel on to a warp beam. The procedure is as follows:(a) Ends in closely spaced sheet form (approximately loom-warp sett), withdrawn from a warping creel, are wound on the machine reel to loom warp length.(b) Each such sheet of ends is called a 'section'.(c) Stability of the yarn-build of the first section on the reel is obtained by moving the section sheet laterally at a regular rate as winding proceeds, so that its outer edge is supported by a fixed or adjustable incline fitted at one end of the reel.(d) When the first section is complete, the other edge of its build on the reel is a replica of the original incline. Sections to the number required for the complete warp are wound similarly.(c) Fancy warps are prepared by 'dressing' yarn packages in the creel for each section in conformity with the warp pattern plan.(f) Section sheets are attached to a beam and withdrawn simultaneously from the reel by rotation of the beam. This unrolling is controlled to provide suitable warp tension for winding the warp on to the beam. As beaming-off proceeds, the warp beam is moved laterally at the same rate but in the direction opposite to that of the section during warping. This ensures that the complete warp sheet runs from the reel to between the beam flanges without the need for lateral deviation.
Note: The efficiency of a section-warping machine is normally of the order of 25-30% because warping ceases during the beaming stage. Single-stage section-warping machines (without a beaming mechanism) are designed with interchangeable reels to improve warp output. The reels may be either of normal capacity (one warp of loom-beam length) or of large capacity (several warps of loom-beam length). Warp from either type may be transferred to warp beams in a beaming machine or on to loom beams in a warp-sizing machine. In each method, a reel is traversed at the same rate as during warping but in the opposite direction.
2. A two-stage-machine method of preparing a warp on beam, consisting in:
(i) winding 'section' beams;
(ii) assembling section beams in warp-beam form. The procedure is as follows:(a) Ends in closely spaced sheet form (approximately loom-warp sett), withdrawn from a warping creel, are wound on to a beam to loom-warp length. The width of the beam between flanges is equal to the loom warp-sett width of the section sheet. The number of equal-length section beams wound is determined by the respective number of ends in the section and the complete warp.(b) Section beams (with or without flanges) are assembled side by side on the 'shaft' or barrel of a suitable warp beam.(c) Section sheets are then fed simultaneously to a sizing machine (or dressing frame) and taken-up on a loom beam (beam-to-beam-sizing). This method of warping is used for making fancy warps in which the number of ends in a pattern repeat is greater than the number of ends in the warping creel. All sections of the same end-pattern in a warp may be made in succession and afterwards assembled in correct order. Planned asymmetrical stripes may be obtained by reversing the winding-off direction of alternate section beams of one pattern. By such means, the amount of creel dressing is reduced in comparison with that required for section warping 1.

Seed cotton

Cotton which has been harvested but not ginned, so that the fibre is still attached to the seed.

Seed hair

Fibres growing from the surface of seeds or from the inner surfaces of fruit cases or pods. Such fibres (seed hairs) are formed by the marked elongation of epidermal cells. The most important example of seed hair is cotton.

Seersucker

A fabric characterized by the presence of puckered and relatively flat sections, particularly in stripes, but also in checks.
Note: The effect may be produced in a variety of ways, e.g.,
(i) by weaving from two beams, with the ground ends at a higher tension and the ends for thepuckered stripes woven at lower tension;
(ii) by treatment of cellulosic fabrics, particularly linen and cotton, with sodium hydroxide (caustic soda) solution, which causes the treated parts to contract;
(iii) by using yarns having different shrinkage properties; these yarns may be combined in the warp and/or the weft.

Self-stitching

A compound fabric in which the two component fabrics are held together by one of the following:
(i) centre-stitching, in which a special series of stitching threads, lying between the two fabrics, are interlaced alternately with them and thus bind them together;
(ii) self-stitching, in which threads from one fabric interlace with the other (e.g., by taking a back warp thread over a face weft thread);
(iii) interchanging, in which the two fabrics are so woven as to interchange with each other. In some cases, the fabrics are completely interchanged whereas in others only the warp or weft threads interchange.

Self-twist spinning

A method of spinning a plied yarn by false-twisting two drafted fibrous strands in order to insert alternating S and Z twist along their lengths. The strands are then brought into contact along their lengths so that their untwisting torques coincide and cause the strands to twist around each other producing a plied yarn termed a self-twist yarn or ST yarn.
Note: The alternating-twisted strands are termed AT-strands.

Self-twist yarn

An inherently twist stable, 2-ply yarn structure having alternating S and Z ply twist strands (see twist direction). The two strands are themselves twisted with alternating S and Z twist prior to being plied.
Note 1: The alternating twist present in the strands and in the resulting yam takes the following change of order: Z and S in the strands give S and Z respectively in the self-twist yarn.
Note 2.. The repeated pattern in the self-twist yarn is S twist-no twist-Z twist. The total length of this pattern is called the cycle length. The no-twist length is shorter than the twist lengths and is called the twist-change-over zone.
Note 3: The lengths of S and Z ply twist are essentially equal.

Selvage

Synonym of selvedge.

Selvage Or Selvedge

The narrow edge of woven fabric that runs parallel to the warp. It is made with stronger yarns in a tighter construction than the body of the fabric to prevent raveling. A fast selvage encloses all or part of the picks and a selvage is not fast when the filling threads are cut at the fabric edge after every pick.

Selvedge (knitting)

When used without qualification, the longitudinal edge of a fabric or a garment panel produced during knitting. The term can also be applied to fabric in which the yarn is cut rather than turned at the end of a course of loops.

Selvedge guider

An electronic or mechanical device for presenting fabric to stenter pins or clips.

Selvedge uncurier

A device for straightening selvedges and fabric edges which have rolled during processing.