SEAMS 11TE74

Contents• Introduction• Garment• Seam • Types• Procedure• Strength• Testing• Factors

Introduction

Need of seam : for bringing fabric in any shape we cut fabric and join its all parts by the help of seam like in apparel , or any their use.

Repair tear fabric

Stitch Vs Seam

Actually Seam is a part of garment manufacturing

Seam means joining the two or layers of a fabric by stitching process

Types

• four basic types of seams according to Wikipedia. Are these

• Plain seams • French seams • Flat or abutted seams • Lapped seams

plain seam

most commonly usedeasiest to sew

French seam • Make the inside of garments as neat as the right side .• Clothing for babies and on thin fabric • 1/8 inches is equivalent to 3.17

flat or abutted seam• strongest seams• often sewn on thick fabrics• Jeans

lapped seam• the two layers overlap with the wrong side

of the top layer laid against the right side of the lower layer

A TABLE FOR DIFFERENT TYPES OF SEAM & THEIR EXAMPLE

Finishes

• A seam finish is a treatment that secures and neatens the raw edges of a plain seam to prevent raveling, by sewing over the raw edges or enclosing them in some sort of binding.

• Good Seams: It means smooth fabric joins with no missed or uneven stitches and no damage to the material being sewn.

Performance of Seams It means the achievement of strength,

elasticity, durability, security and comfort, and the maintenance of any specialized fabric properties such as waterproofing or flame proofing.

1. Seams must be strong as the fabric, in directions both parallel to and at right angles to the seam.

2. Seams must be durable to the kind of abrasion experienced in washing and wearing as well as secure against fraying apart or the unraveling of the stitches.

3. A seam in a close fitting garment must not present an uncomfortable ridge or roughness to the skin.

4. It must not damage the fabric along the stitch line.

SEAM SLIPPAGE• Separation of the fabric at the seam, causing gaps or

holes or Fabric layers opening under load . • Many factors are identified which have direct or indirect

influences on seam slippage like fabric density (picks per inch and ends per inch), shrinkage of the fabric, SPI or stitch density, weight of the fabric, rpm of the machine, GSM of the fabric , cover factor of the fabric etc.

• Seam slippage occurs on woven fabric, when yarns slide together along other yarns or a line of stitching.

• Seam slippage occurs with a low stitch count, insufficient tension on threads, or improper stitch and seam selection.

TestingThe British Standard test for seam slippage is a test of the second type. Five warp and five weft specimens each 100mm X 350mm are used. Each sample is folded 100mm from one end and a seam is sewed 20mm from the fold line using the special sewing thread and sewing machine settings which are detailed in the standard. The layout of the sample is shown in Fig. After sewing the folded part of the fabric is cut away 12mm from the fold line leaving the seam 8mm from the cut edge. A standard strength tester equipped with 25mm grab test jaws is used, the gauge length being set to 75 mm. FigJust before the test the sample is cut into two parts one with the seam and one without but with each part containing the same set of warp or weft threads. The sample without a seam is first stretched in the tensile tester up to a load of 200N and a force elongation curve drawn. The matching sample with the seam is then tested in the same way making sure that the force elongation curve starts from the same zero position.

• In order to find the force required to open the seam a given distance, the separation of the curves is measured and this distance is added to the seam opening specified (usually 6mm but some specifications require 5 mm) making appropriate allowance for the horizontal scale of the chart. Next the point on the curves where there is a separation of this distance is located and the value of load at this point is read off the chart. If the curves do not reach the specified separation below 20ON then the result is recorded as 'more than 20ON'.

Factors Seams may be sewn or constructed

improperly with insufficient stitches per inch.

Very shallow seam allowances may have been used. Strain on the fabric at the seams will allow slippage to take place. If the item is an extremely tight fit, excessive stress and strain occurs during wear.

LITERATURE REVIEW 1). According to Ms. Anita a Desai [02 ], this paper

represents the Seam strength and Seam slippage of fabrics. Different types of stitches and different types of sewing thread s and their affect, construction on the above mentioned properties have also been reviewed.

• The five major contributors to seam strength include:-– 1. Fabric type and weight.– 2. Thread type and size.– 3. Stitch and seam construction.– 4. Stitches per inch.– 5. Stitch balance.

• Below is one formula that was developed for estimating the seam strength on woven fabrics.

• SPI* Thread Strength* 1.5 = Estimated seam strength (for lockstitch 301).

Seam slippage also depends upon different force like breaking force of rupture, a minimum elongation, or both are required to determine the sewn seam slippage, or seam integrity of a fabric for a specified end use.• So a thorough knowledge of different types of stitches, analyze the different parameters of sewing thread and also different types of sewing threads and their affect o is required for the garment manufacturing process. Also this paper reviews about thread construction, twist, application, size and other parameters. 2). According to Bharani M., Shiyamaladevi P.S.S. and Mahendra Gowda R.V [03], In the present work, the quality of fabric samples was controlled, now the garment longevity depends on the seam parameters like various factors such as seam strength, seam slippage, seam puckering and yarn severance. • In the present work, fabrics of different blend proportions i.e., cotton and was prepared with different woven structures like plain, twill, satin. These fabrics were treated with fabric softener like silicone. •The fabric samples of plain weave were found to have greater seam performance than the twill and satin. Various other factors influencing the seam strength and seam slippage are also discussed in detail. The final observation table as per there is as furnished below :-

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