SOP: Standard Operating Procedure of Skewing / Twisting Test | Garments-Info

SOP – Skewing / Twisting Test

Standard Operating Procedure of Skewing / Twisting Test

Objective

·        This test aims to determine the yarn weaving distribution within the fabric cross sectional area. Results will show the direction of fabric grain line.

·        To identify probable Fitting and finishing defect caused by bowing fabric. This type of defect not only affects the fitting of the garment (Twisting legs in pants) but also affect the availability and/or presentation. It is less noticeable in solid color but more critical on stripes or checks design.

·        To be able to identify whether the fabric being inspected contains certain amount of bowing or skews.

·        To anticipate probable production difficulties and to prompt the factory in taking immediate corrective steps in making markers and developing production processes in order to ensure that garment shape shall not be distorted or disfigured.

Scope

The procedure covers one of the fabric inspection activities.

Authority

The procedure is being controlled by the Head of Quality.

Responsibility

Execution and proper maintenance of the procedure lies on the fabric inspector.

Procedure

·        The fabric inspector shall identify the amount of skews and its location whether at center or at sides.

·        The fabric Inspector who needs to determine the amount of skews in the fabric shall perform the following tasks.

·        Tear 8” from one end of the roll.

·        Align the torn edge across a pre-drawn straight line on a table.

·        Check for alignment and note down any distortion along the torn edge against the pre-drawn line.

·        The amount of skew can be measured by measuring the distance of skew from the pre-drawn line. Refer to figure 1 below.

·        If a torn edge is completely aligned with the pre-drawn line, fabric shows no bowing problem.

·        Otherwise, it indicates certain amount of skew or bowing on the fabric.

·        Formula to determine the amount of skew (%) =

Distance of skews (inches) AB or AC X 100

Fabric Width AD (Inches)

Figure 1 – Diagram of checking Skewing on Fabric

Diagram of checking skewing on fabric

Tolerance

Customer/supplier shall be immediately informed if the amount of skews exceeds 3% or as per buyer standard.

Skewing/Twisting – If fabric fails for skewing/twisting.

·        Make garment mock ups using normal/line marker and review the garments for twisting.

·        If decision cannot be made, go for normal/Line markers to make actual garments. Review these garments for twisting.

·        In case of special marker required, need to get compensation from supplier.

Hope this article will help you to know about SOP of Skewing / Twisting Test.