Fabric specification calculation is a core process linking design, production and trading. For fabric designers, it provides scientific basis，guiding factory production; For sales department, it is an essential tool for client communication, quotation and cost control. Mastering this skill, being able to quickly calculate product cost, provide accurate & timely quote and  identify key cost factors precisely. Within entire fabric preparation workflow, dyeing process as one of the critical step affecting fabric quality and specification, influences the accuracy of all calculation parameters directly.

Link Between Raw Material Quantity Calculation and Dyeing Process

First step of fabric specification calculation is determining raw material quantity, which involves various process shrinkage rate, such as fiber shrinkage, twist shrinkage and weaving shrinkage. Many of these are closely related to dyeing and finishing process. For example:

Raw Material Shrinkage: Different fibers behave differently during dyeing. Cellulosic fiber like cotton, linen or viscose, may have shrinkage about 2% after dyeing or bleaching, while synthetic fiber like polyester filament is significantly affected by heat-setting processes.

Dyeing and Finishing Shrinkage: The ratio between greige fabric length and finished fabric length, directly determined by dyeing and finishing processes. Stable dyeing process effectively controls shrinkage variation, ensuring fabric weight, width and other related specifications meet design expectation.

If temperature, tension or time is not controlled properly during dyeing, shrinkage rate can deviate from expectation. It affects whole batch's material calculation, leading to cost errors or quality issues. This is precisely why textile manufacturers need high-performance, controllable yarn and fabric dyeing equipment to ensure process consistency.

Fabric Weight Calculation: Key Role of Dyeing and Finishing 

Formulas for calculating finished fabric weight per meter and GSM, refining weight loss ratio and dyeing & finishing shrinkage rate are two crucial variables. Refining weight loss ratio reflects weight loss of fibers during dyeing and finishing (e.g., ~75–80% for silk, ~99% for synthetics). Dyeing and finishing shrinkage rate is directly related to length change between greige and finished fabric.

This data is not only used to calculate weight but also forms basis for cost quotation. If dyeing stage is unstable, weight loss ratio and shrinkage rate will fluctuate. This can cause fabric weight to fall outside acceptable tolerances in mass production, impacting customer trust and profit margins directly. Therefore, investing in precise and repeatable yarn and fabric dyeing machinery is key to achieving standardized fabric specification.

How Dyeing Processes Affect Component Ratio Calculation in Multi-Fiber Fabric?

For blended or interwoven fabric, different fibers exhibit vastly different dyeing behaviors. For instance, when silk/linen blended yarn is interwoven with viscose yarn, the dye uptake, shrinkage and weight loss ratio must be precisely managed during dyeing due to their different fiber compositions. As shown in the example as below, calculating the percentage of each component relies on its specific weight loss ratio and process shrinkage. These parameters must remain stable throughout the dyeing process to ensure the final composition matches the design.

For fabrics woven or blended from two or more types of raw materials, it is essential to calculate the proportion of each material. The calculation method is as follows:

Content of Material A = (Weight of Material A × Proportion of Material A × Refining Yield of Material A) ÷ (Weight of Material A × Refining Yield of Material A + Weight of Material B × Refining Yield of Material B) × 100%

Example:

A product uses warp yarn of 120N/2 silk-linen blended yarn (70% silk, 30% linen) and weft yarn of 40S/2 bright rayon yarn.

Finished fabric width: 140 cm, plain weave

Finished warp density: 28 ends/cm, finished weft density: 24 picks/cm, greige fabric weft density: 23 picks/cm

Considering various factors, the estimated weaving shrinkage is about 5%, silk process shrinkage is 2.5%, weft width shrinkage is about 10%, and viscose staple fiber process shrinkage is 2.0%.

Warp yarn quantity (g/m) = Finished warp density × Finished fabric width × (1 + Process shrinkage) × (1 + Weaving shrinkage) × Yarn fineness ÷ 9000

= 28 × 140 × (1 + 5%) × 1/60

= 65 g/m

Weft yarn quantity (g/m) = Finished weft density × Finished fabric width × (1 + Weft weaving shrinkage) × (1 + Process shrinkage) × Yarn fineness ÷ 9000

= 140 × 24 × (1 + 10%) × 0.59/20

= 109 g/m

Finished fabric weight per meter (g/m) = (Warp yarn quantity × Refining yield + Weft yarn quantity × Refining yield) ÷ Dyeing and finishing shrinkage

= (65 × 0.95 + 109 × 0.97) ÷ 0.96

= (61.8 + 105.7) = 167.5 ≈ 168 g/m

Fabric weight per square meter (g/m²) = Weight per meter ÷ Fabric width

= 168 ÷ 1.4

= 120 g/m²

Among these:

Silk content = (Weight of silk component × Silk proportion × Silk refining yield) ÷ (Weight of silk component × Refining yield + Weight of rayon yarn × Refining yield)

= (65 × 0.7 × 0.95) ÷ (70 × 0.95 + 109 × 0.97) × 100%

= 43.2 ÷ 167.5 × 100%

= 26%

Linen content = (Weight of linen component × Linen proportion × Linen refining yield) ÷ (Weight of linen component × Refining yield + Weight of rayon yarn × Refining yield)

= (65 × 0.3 × 0.95 × 100%) ÷ (65 × 0.95 + 109 × 0.97)

= 18.5 ÷ 167.5 × 100%

= 11%

Rayon content = (Weight of rayon yarn × Rayon refining yield) ÷ (Weight of warp yarn × Refining yield + Weight of rayon yarn × Refining yield)

= (109 × 0.97 × 100%) ÷ (109 × 0.97 + 65 × 0.95)

= 105.73 ÷ 167.5 × 100%

= 63%

From the above calculations, warp yarn quantity of the product is 65 g/m and weft yarn quantity is 109 g/m. Based on this, adding a certain percentage of waste yarn according to the product process, combined with the market price of raw material, provides relatively accurate raw material cost. Adding weaving and dyeing processing costs shows the base price of product.

This requires consider select appropriate textile dyeing equipment. For example:

Yarn Dyeing Machine: Used for yarn-dyed fabrics, allowing pre-dyeing of warp or weft yarns to ensure color uniformity and shrinkage control.

Hank Dyeing Machine: Often used for yarns like wool or cotton that require gentle handling, better preserving yarn elasticity and hand-feel.

Fabric Dyeing Machine: Used for piece dyeing of finished fabrics (open-width or rope form), effectively controlling width and weight variation.

Why Choose Professional Dyeing Machine Manufacturer?

As one of factories specializing in dyeing equipment manufacturing, Wuxi Shin Tong Yunn Machinery Technology Co., Ltd understands the impact of dyeing processes on fabric specification stability. Our dyeing machines, from yarn to fabric dyeing, is designed to deliver:

• Precise control of process parameters, helping customers stabilize shrinkage and weight loss ratios.
• Energy and resource efficiency, reducing consumption of dyes, water and energy, thereby indirectly optimizing fabric costs.
• Automated and intelligent operation, minimizing human error and improving batch-to-batch consistency.

Whether the need is for hank dyeing solution or high-efficiency fabric dyeing machine, as reliable dyeing machine manufacturer, we provide customized dyeing machine and process support. We ensure every stage from raw material to finished product meets specification requirements, helping our clients improve quotation accuracy and market competitiveness.

While fabric specification calculation involves numerous parameters and formulas, it relies on precise control fundamentally at every production stage—especially dyeing process. By using stable and advanced dyeing equipment, manufacturers not only ensure reliable fabric quality but also control costs at the source, enabling more accurate pricing and efficient production management. As dyeing equipment manufacturer in textile industry, we are committed to supporting global textile companies with our expertise and reliable products.

This article is supported by Wuxi Shin Tong Yunn Machinery Technology Co., Ltd. We are dedicated to developing efficient and precise dyeing machinery, including yarn dyeing machine and fabric dyeing machine, helping textile companies achieve process standardization and cost optimization.