Raschel Bag: What the Knitted Mesh Must Do and How It Is Made
A raschel bag is a mesh bag knitted on a raschel warp knitting machine: an open structure that carries weight while letting air through. Woven sacking and film packaging cannot offer both at once, which is why produce packers and industrial storage users specify knitted mesh.
Everything that makes one raschel bag better than another is set at the knitting stage, not in converting. The sections below start from what the bag has to do and work back to the machine settings that decide it.
What a raschel bag has to do in use
| Sector | What the bag has to do |
|---|---|
| Agriculture | Store fruit, vegetables and potatoes with airflow through the bag so produce stays fresh longer; strong enough to protect during transport, light enough to keep freight cost down, and stackable without damage |
| Retail and supermarkets | Light and strong for fresh produce, open structure to prevent moisture build-up, and visibility of the product inside; reusable rather than single-trip |
| Logistics and industrial | Breathable, strong and lightweight for moving and storing raw materials; the open design reduces condensation, which keeps stored material dry in a warehouse |
The common thread is airflow. Condensation is what spoils produce and degrades stored material, and an open knitted structure manages it passively, with no coating, no perforation step and no additional cost per bag.
Three ways a mesh bag fails
Mesh bags fail in predictable ways. The structure stretches out of shape under load. The aperture closes, so produce cannot breathe. Or an edge unravels in handling. A buyer sees these as bag complaints; a mill should read them as knitting faults, because none of the three can be repaired after the fabric leaves the machine.
There is a fourth failure that never reaches a customer. In netting, a single dropped course runs the length of the piece. A fault that goes unnoticed does not produce seconds, it produces a full roll that cannot be converted into bags at all.
How the mesh is built on the machine
The knitting elements hold the structure. An individual needle bar and tongue bar give the control needed for fine, detailed fabric, and they are what let you tune strength and flexibility together instead of trading one for the other. A stitch comb bar and a knockover comb bar keep loop formation even, so the material stays stable through the run and holds its shape afterwards.
Four ground guide bars set how much pattern freedom you have. For bag work that translates directly into aperture geometry and mesh variation: the difference between one product and a range.
The step-by-step process is covered in how raschel bag making machines work, and the full machine specification is on our raschel warp knitting machine page.
Beam configuration decides run length
Bag production is high volume and low margin, so the number that matters day to day is how long the line runs before it stops.
| Configuration | Beam positions | Sectional beam flange |
|---|---|---|
| Standard | Three | 32 in |
| Optional | Four | 21 in |
| Optional | Four | 30 in |
The 32 in standard setup carries more yarn per beam and suits long uniform runs of a single bag specification. The four-position options trade beam size for feed flexibility, which is the better fit when you switch between mesh types often. Flange diameter is a decision you make once for the whole plant: running two flange sizes means two sets of handling equipment and two spares lists.
Monitoring that protects the roll
Laserstop technology halts the machine on a detected fault, and an integrated camera checks fabric quality in real time. Given what one dropped course does to a roll of netting, this is where the real saving on a bag line sits.
The GrandStar Command System is the operator interface, with setup and adjustment through simple commands. On a bag line that matters mostly at changeover, which comes round more often than on a fabric line because bag specifications are short-lived.
When a raschel bag is the right packaging, and when it is not
If you pack produce or store raw material that suffers from trapped moisture, and you need the bag to carry load and show its contents, then knitted raschel mesh is the right format, and the configuration above fits volume production: four ground guide bars for aperture range, three beam positions on 32 in flanges for run length, and Laserstop monitoring to protect the yield.
This does not apply if your product is closed woven sacking or coated film packaging. Those are different processes, not a different setting on this machine. It also does not apply to fine apparel-grade fabric, where the bag configuration is the wrong element set entirely.
Scoping a line
Grand Star Technology has built warp knitting machines since 2012. Training comes as manuals, online guides, video and on-site sessions, so operators do not depend on one commissioning visit, and after-sales teams operate in Turkey, India, Vietnam, Indonesia and the USA. Buyers in India will find the local specification questions in raschel bag making machines in India. Replacement elements are listed on the group warp knitting spare parts pages.
If you are scoping a line, send your bag dimensions, target mesh aperture, yarn type and monthly volume through our contact page. Those four figures decide beam configuration and working width.
Frequently Asked Questions
What is a raschel bag?
It is a mesh bag knitted on a raschel warp knitting machine. The open structure carries weight while letting air pass, a combination that woven sacking and film packaging cannot provide. Growers, supermarkets and warehouses use it for produce and raw materials that spoil when moisture is trapped.
Why does open mesh keep fruit and vegetables fresh longer?
Airflow through the knitted structure prevents moisture build-up and condensation, which is what spoils produce in storage and transport. It works passively, with no coating and no perforation step, while staying strong enough to protect the contents during handling and light enough to keep freight cost down.
Why do some mesh bags stretch, close up or unravel?
All three faults are set at the knitting stage. The needle and tongue bars, the stitch comb and the knockover comb control loop formation, and the ground guide bars set aperture geometry. If those are wrong, the structure deforms under load, the openings close or an edge runs in handling.
How many warp beam positions does the line need?
The standard configuration has three positions for sectional beams with a 32 in flange, which carries more yarn and suits long runs of one specification. Four-position options take 21 in or 30 in flanges and give more feed flexibility when mesh types change often. Standardise on one flange size across the plant.
Hey, I’m Vincent!
Solving complex challenges with precision and creativity in the warp knitting industry. Passionate about advancing textile engineering and turning innovative ideas into reality. Shaping the future of warp knitting.
