Most bag orders go wrong in the same place. The buyer asks for a 50 kg bag, the supplier quotes whatever is cheapest that week, and both sides think they agreed on the same thing. They didn’t. Getting PP woven bag specifications in writing is the only way to avoid that.
A 50 kg sack can be thin and breathable, or thick, laminated and printed in eight colours. The difference shows up later, when bags split on the forklift or the flour inside picks up moisture. These are the details worth putting in the order.
What a PP woven bag is made of
The fabric starts as polypropylene film. Makers slit the film into narrow tapes, stretch them, and weave them on circular or flat looms. Then they cut, print and stitch the woven fabric.
That tape structure explains why these bags are so strong for their weight. Thousands of stretched tapes share the load, instead of a single sheet of plastic.
GSM sets the strength and the price
GSM means grams per square metre of fabric. A higher GSM puts more plastic into every square metre, which usually means a stronger bag and a higher price.
Still, there is no single correct GSM for a 50 kg bag. Listings for 50 kg sacks in the regional market run from about 50 GSM up to 120 GSM. The right figure depends on the product, how you fill it and how roughly people handle the bags.
Go heavier when:
- the product is sharp or abrasive, such as aggregates, salt or crushed minerals
- you stack bags high or workers move them with hooks
- the bags travel a long way or sit outdoors before use
Go lighter when the product is soft, the bags make one trip from factory to customer, and price matters most. If you are unsure, test two weights side by side. A few fils more per bag is cheap compared with one burst pallet.
Mesh and denier
Mesh describes how tight the weave is. Suppliers usually write it as tapes per inch in each direction, such as 10×10 or 12×12. A tighter mesh holds fine powders better and gives a smoother surface for printing.
Denier is the weight of the tape itself: the mass in grams of 9,000 metres of tape. So thicker tapes make a stronger fabric at the same mesh.
GSM is the result of the two together. That means two bags with the same GSM can still behave differently. One might use fine tapes in a tight weave, while the other uses coarse tapes in an open weave. For powders, ask about the mesh as well as the GSM.
Laminated or unlaminated?
Unlaminated bags breathe, because air passes through the weave. That suits products such as some grains, seeds and animal feed.
Laminated bags have a thin plastic coating, typically a film of around 15 to 30 GSM, bonded to the woven fabric. The coating seals the weave, keeps moisture out and stops fine powder sifting through. It also gives a smooth surface for sharp printing.
In a humid coastal warehouse, lamination is usually worth it for anything that cakes, such as sugar, salt, flour or fertiliser.
BOPP bags go a step further. They carry a printed BOPP film bonded onto the woven fabric, which gives photo-quality graphics for retail products like rice and pet food.
Liners, UV treatment and other options
A loose PE liner goes inside the woven bag when the product has to stay completely dry, or must not touch the woven fabric at all. Many food ingredients and moisture-sensitive chemicals ship this way.
Manufacturers add a UV stabiliser to the polymer when bags will sit in the sun. Untreated polypropylene breaks down in strong sunlight, and in a UAE summer that happens quickly. If there is any chance of outdoor storage, put UV stabilised in the order.
Anti-slip printing adds grip so stacked bags don’t slide on a pallet. Standard woven bags use flexographic printing, usually in up to eight colours.
How to size a bag for 25 kg or 50 kg
Bag size depends on how much space the product takes up, not just its weight. Fifty kilograms of cement fits in a much smaller bag than fifty kilograms of flour, because flour is far lighter per litre.
The reliable method is a fill test with a sample bag. Tell the supplier the product and the fill weight, and ask for samples before the production run. Suppliers quote bag width as the flat width. Ours run from 27 cm to 75 cm, and we make the length to order.
For loads well beyond 50 kg, look at jumbo bags instead. A single FIBC carries anywhere from 500 kg to 2 tonnes.
PP woven bag specifications to put in your order
Put these in every enquiry and the quotes you get back will be comparable:
- the product and the fill weight
- flat width and length
- GSM, and the mesh if the product is a powder
- laminated or unlaminated
- a PE liner, if needed
- UV stabilised or not
- top and bottom finish, for example open mouth with a stitched bottom
- print colours and artwork
- quantity and delivery date
A bag is only as strong as its seam, too. Match the closing thread to the bag weight. Our guide to bag closing thread covers thread counts and machines.
Ordering PP woven bags in the UAE
Jazeera International supplies PP woven bags from Dubai in any colour, laminated or unlaminated, with PE liners and UV stabilisation on request. Send us the product, fill weight and quantity on +971 56 158 9555 and we will suggest a specification and a price.
Frequently asked questions
What GSM should a 50 kg PP woven bag be?
There is no single standard. Regional listings run from roughly 50 to 120 GSM. Heavier, sharper or more roughly handled products need the higher end of that range.
Are PP woven bags waterproof?
Unlaminated bags are not. Laminated bags resist moisture well, and adding a PE liner makes them close to waterproof for most storage.
Can PP woven bags be stored outdoors?
Only if they are UV stabilised. Untreated polypropylene weakens quickly in strong sun.
What does mesh mean on a woven bag?
It is the number of tapes per inch in each direction, such as 10×10. A tighter mesh holds fine powders better.
