Part 2: Cutting, Component Manufacturing, and Sewing

Are you curious about how bulk bags are made and how they’re strong enough to hold thousands of pounds of material? In Part 1, we reviewed how our bulk bag fabrics are produced through extrusion, weaving, and coating. Now, let’s dive into the second phase of production, which includes fabric cutting, component manufacturing, and sewing.

Cutting

In the cutting stage, the woven fabric rolls produced during weaving are moved to the cutting floor. Here, the fabric is cut into specific shapes and sizes based on the finished bag’s specifications. These cuts determine the shape of the bag’s body panels, base and top panels, duffle or spout dimensions, and overall bag style. Measurements are programmed automatically to ensure precise and equal cuts according to the specifications.

Component Manufacturing

This stage involves two sub-stages: printing and webbing.

Sub-stage 1: Printing

After the fabric is cut, the printing plan is defined by the planning team. Once print plates are produced, the data is sent to an automatic printing machine. Impressions, company logos, and colors are then applied to the fabric panels before any sewing processes begin.

Sub-stage 2: Webbing

During this stage, various webbing components are produced, including lift loops, perimeter bands, belly bands, and web ties. Polypropylene tapes are woven on flat looms in the warp direction, and multifilament yarn is woven in the weft direction to produce webbing that supports a 6,000 lb break strength. The Quality Team then checks and approves the mechanical properties and appearance of the fabric.

Sewing

Once all the fabrics are cut, components are produced, and the technical team has reviewed the production plan, the materials are brought onto the production floor for sewing. The line plan is set up based on the attachments and components of each bag. Sewing generally follows this sequence: spouts are attached to their appropriate panels, the body panels of the bag (the “box”) are sewn together using a single safety stitch, and finally, the web components and accessories are attached with the finishing stitch. Different operations are carried out at their respective workstations by trained specialists to produce the finished FIBC bag.

HOW BULK BAGS ARE MADE: PART 1

Part 1: Extrusion, Weaving, Coating

Bulk bags are crucial for transportation, but how are they crafted to be so robust? Here’s a breakdown of how FIBC fabrics and bulk bags are made.

What is FIBC fabric? FIBC fabrics, primarily made from polypropylene, are coated with a synthetic film of polypropylene and polyethylene. These fabrics are designed to be strong and versatile, ideal for transporting dry and flowable products.

How is FIBC fabric made? FIBC fabrics are created through the following process:

  1. Extrusion
  2. Weaving
  3. Coating (Lamination)

Extrusion In the extrusion process, raw materials are melted into tapes of specific measurements. The ingredients include polypropylene granules, a small amount of calcium carbonate, a UV stabilizer, and colored pigments if needed. These tapes are then loaded onto bobbins for weaving.

FIBC Fabrics typically consist of:

  • Polypropylene 94.33%
  • Calcium 3.77%
  • UV treatment 2%

Weaving During weaving, the polypropylene tapes from the extrusion process are loaded onto looms. The fabric that forms the bulk bag’s body is woven into shape with warp (vertical tapes) and weft (horizontal tapes) generally at 10-warp x 10-weft tapes per square inch. This fabric has small gaps, making it breathable, which is excellent for some materials but not suitable for others.

Coating (Lamination) For certain applications, the fabric is treated with a laminate coating. In this process, the fabric passes through a thin liquid film of PP & LDPE material, then solidified by chilled rollers. This coating seals the weave’s voids, enhancing the fabric’s physical properties, making it suitable for transporting fine or flowable products and protecting them from moisture.

The lamination material typically consists of:

  • PP 350 FG 75%
  • LD 1070 LA17 25% (No filler used in the lamination process)

After coating, if applicable, the woven fabric is wound onto large spools and stored until it enters the cutting process, marking the start of Phase 2 of production.

Rising Demand for Food Grade FIBC Bulk Bags: Implications for Sales and Market Expansion

The FIBC market is forecast to expand at 5.4% CAGR over the estimated period, as per FMI’s analysis. The industry’s size is predicted to reach a market value of US$ 7.5 billion in 2023.

The demand for food grade FIBC bulk bags is on the rise, notably impacting sales as these bags are increasingly sought after by food companies. Traditionally utilized in the chemical industry, FIBCs are now gaining traction in the food sector due to their suitability for commercial food operations.

Key attributes driving this surge in demand include their high load-carrying capacity, versatility, reusability, cost-effectiveness, and eco-friendly materials. FIBCs offer optimal protection for food products through features such as dust-proof seams and laminated fabric sides, guarding against moisture and maintaining product integrity.

Innovative bulk bags incorporating polyethylene, foil, and other lining materials are gaining popularity for their ability to shield food items from harsh environments, spillage, and damage. Furthermore, the ease of customization and quality printing options enable end users to establish their brands effectively and promote products with confidence.

Top Highlights from the FMI’s Analysis of the FIBC Market: 

  • The Europe region acquired a massive share of 32.4% in the FIBC industry in 2022. Regional growth is expected to continue exhibiting an upward trajectory in the coming years.
  • In the overall FIBC industry, North America gained a 24.9% market share in 2022.
  • The United States FIBC industry is forecast to garner more than 18.9% value share in the year 2023.
  • The German market is expected to procure a value share surpassing 5.6%% in 2023.
  • The Japanese FIBC industry is projected to obtain a value share exceeding 8.1% in 2023.
  • The India FIBC industry is forecast to expand at a CAGR of 6.9% over the forecast period.
  • The Chinese FIBC industry is projected to accelerate at a CAGR of 5.7% over the estimated period.
  • The United Kingdom is anticipated to expand at a CAGR of 3.1% from 2023 to 2033.
  • Based on capacity, the ‘above 750 kgs’ segments gained 55.5% market share in 2022.
  • Based on end-use, chemicals, and fertilizers acquired a 41.1% value share in 2022.

Innovation Watch: Key Developments in the Market

  • In May 2023, Packem Umasree commissioned a sustainable FIBC plant in Ahmedabad. This is the company’s first plant in India and is second to the one built in Brazil. The company manufactures 100% sustainable FIBCs or jumbo bags made of recycled PET. The Brazil unit of the company serves the local market, whereas the new plant in India is projected to cater to markets outside of Brazil. The company is expected to export a substantial proportion of the Ahmedabad plant’s output to Europe and North America.
  • Global-Pak announced a new recycling program in September 2022. The corporation is working with PureCycle to process and recycle bulk bags. PureCycle deploys a solvent-based purification technology to process polypropylene waste into an extremely pure resin that can be constantly reused and recycled. One of the many products the company is interested in is used bulk bags.

Global FIBC Industry by Category

By Packaging Type:

  • Q-bags
  • Baffle Bags
  • Circular Bags
  • 6-panel
  • Others

By Capacity:

  • Upto 250 Kg
  • 250 kgs – 750 Kgs
  • Above 750 Kgs

By End User:

  • Building & Construction
  • Chemicals & Fertilizers
  • Food Products & Agriculture
  • Pharmaceuticals Products
  • Mining

By Region:

  • North America
  • Latin America
  • Europe
  • Middle East and Africa
  • East Asia
  • South Asia
  • Oceania

FIBC Material: What Are Bulk Bags Made Of?

Bulk bags are made of polypropylene fabric, a strong, durable, and thermoplastic polymer FIBC material that’s resistant to moisture, chemicals, and UV radiation. Coatings provide extra protection, and bags feature woven polypropylene lifting loops for easy handling.

There are a number of bulk bag specs that are designed to meet Department of Transport (DOT) requirements for transport, including the:

  • Thickness of individual threads (denier)
  • Fabric weight (GSM)
  • Strength of the yarn and fabric.

From these engineering specs, each bag is specifically designed to pass a number of stress tests, including drop and jerk forces, that could affect the integrity of each bag during transport.

When purchasing an FIBC, the most important bulk bag spec is the bag capacity (or bag size), which can range from 500 to 4,000 pounds when filled.

Also, the styles and types of FIBC bags should be considered when choosing an FIBC to meet your product storage and transport applications:

  • Type A FIBC: No Electrostatic Protection
  • Type B FIBC: Surface Breakdown Voltage of <6kV
  • Type C FIBC: Electrically Conductive or Groundable
  • Type D FIBC: Static Dissipative

Within these FIBC bag types, you will find different styles to meet your bagging needs, including rectangular or four-panel bags, duffle top bags, and circular bulk bags. For each bag style, the manner in which they are constructed will be similar, other than the type of material, size, and shape.

If you’re unsure which of these bags you need, get in touch with the team here at Palmetto Industries so we can discuss your needs further.

The FIBC Bags Manufacturing Process

The FIBC bags manufacturing process we take is as follows:

  1. Extrusion
  2. Weaving
  3. Vacuuming
  4. Lamination
  5. Printing
  6. Cutting
  7. Sewing
  8. Final Testing

Let’s take a look at each of these steps in more detail so you can see exactly how we optimize your product for your needs:

1. Extrusion: Feeding in the FIBC material

The making of a bulk bag begins with the feeding of polypropylene (PP) resin and other additives into an extruder to produce PP tapes that vary in thickness and width.

The melted resin forms PP sheets that are stretched by rollers, then cut.

2. Weaving

The tapes are then wound onto bobbins to start the weaving process which will create the FIBC fabric.

The fabric weaving is performed on special looms to make either circular shaped bags or U-panels for the various other FIBC bag styles.

3. Vacuuming

If the fabric is to be coated, the bags are vacuumed to release dust particles, and the bag is then passed through a static eliminator.

4. Lamination

A lamination process then applies a protective coating of polypropylene which will increase the bags’ resistance to moisture and sifting. Breathable fabric bags are left uncoated.

5. Printing

At this point, the bags are printed with an FDA-approved printing ink, suitable for food contact. The ink that is used will dry quickly to eliminate smears or running.

6. Cutting

Next, a computer program controls the precision cutting of the woven fabric from the rolls into the required sizes for the bag assembly process.

7. Sewing

Finally, highly-trained employees complete the manufacturing process by sewing the fabric pieces together to create each bulk bag. All bags are sewn in an FDA-approved clean room to maintain sanitation requirements.

8. Final Testing

While we continuously QA our bulk bags through the manufacturing process, at this stage, filler cords are sewn into the seams and the bags will move on through different types of testing to final approval.

Key Takeaways On The FIBC Manufacturing Process

The FIBC manufacturing process involves several key steps, but, depending on the specific requirements, additional processes may be applied.

For instance, coatings like polyethylene or polypropylene can be applied to enhance moisture resistance, and printing machines may add logos or other information onto the fabric’s surface.

After the fabric is woven and any optional coatings or printing are applied, it is ready for bag construction and final inspection. This meticulous manufacturing process ensures that FIBCs meet industry standards and can withstand the rigors of transporting and storing bulk materials effectively.

Types of Jumbo Bags (FIBC) and Their Applications

Jumbo bags, also known as FIBCs (flexible intermediate bulk containers), are extensively used in various industries for storing and transporting dry, flowable materials. These versatile and durable bags come in different types, each with specific properties and applications. This article explores the four main types of jumbo bags based on their static control properties: A, B, C, and D.

Type A Jumbo Bags:

  • Composition: Made from standard polypropylene (PP) or other non-conductive woven fabrics.
  • Static control: No inherent anti-static properties.
  • Applications: Suitable for non-flammable products such as fertilizers, grains, and chemicals.
  • Precautions: Not recommended for flammable products or combustible environments.

Type B Jumbo Bags:

  • Composition: Similar to Type A, but with an added conductive liner.
  • Static control: Dissipates static electricity up to 6000 volts.
  • Applications: Ideal for dry, powdered, and flammable products like flour, sugar, and resins.
  • Precautions: Avoid using near flammable solvents or gases.

Type C Jumbo Bags:

  • Composition: Combination of conductive and non-conductive PP woven fabrics in a grid pattern.
  • Static control: Requires grounding during filling and discharging to prevent static build-up.
  • Applications: Safe for combustible powders and offers protection in environments with flammable solvents or gases.
  • Precautions: Grounding is essential for safe use. Do not use if damaged.

Type D Jumbo Bags:

  • Composition: Constructed with anti-static and dissipative woven fabrics.
  • Static control: Engineered to prevent sparks, dissipate static charges, and eliminate the need for grounding.
  • Applications: Suitable for highly flammable products and offer the highest level of safety in explosive atmospheres.
  • Precautions: Avoid using if the bag surface is contaminated with conductive materials.

Choosing the Right Jumbo Bag:

Selecting the appropriate jumbo bag type is crucial for safe and efficient product handling. Consider the following factors:

  • Product properties: Flammability, conductivity, and particle size.
  • Intended use: Storage, transportation, or specific process requirements.
  • Environmental factors: Presence of flammable solvents or gases.
  • Regulatory compliance: Adhering to industry standards and safety guidelines.

Conclusion:

By understanding the different types of jumbo bags and their specific properties, businesses can choose the most suitable option for their unique requirements, ensuring optimal product protection, safety, and compliance.

Introduction to FIBC – Jumbo Bag: Understanding the Basics

Flexible Intermediate Bulk Container (FIBC) is a type of large, woven bag used for the transportation and storage of dry, flowable products. Also known as Jumbo bags, Big bags, or Bulk bags, FIBCs are commonly used in various industries such as agriculture, mining, construction, and chemicals.

FIBCs are made of woven polypropylene fabric, which provides strength, durability, and tear resistance. The fabric is sewn together to create a bag with a variety of options for closures, lifting, and filling. FIBCs come in a range of sizes, from small bags that hold a few kilograms to bags that can carry up to 2000 kilograms.

One of the most significant benefits of FIBCs is their ability to reduce the cost and environmental impact of packaging. FIBCs can be reused multiple times, reducing waste and the need for disposable packaging. Additionally, FIBCs are lightweight and take up less space than other packaging options, reducing transportation costs and emissions.

FIBCs have many advantages over traditional packaging methods. They are easy to handle, store, and transport, making them a popular choice for many industries. In addition, FIBCs can be customized to meet the specific needs of a product, with options for coatings, liners, and antistatic properties.

In conclusion, FIBCs are a versatile and cost-effective solution for the transportation and storage of dry, flowable products. Understanding the basics of FIBCs can help businesses make informed decisions about their packaging needs, ultimately leading to cost savings and environmental benefits.