{"id":13203,"date":"2026-04-15T01:27:58","date_gmt":"2026-04-15T01:27:58","guid":{"rendered":"https:\/\/fill-package.com\/?p=13203"},"modified":"2026-04-15T01:27:58","modified_gmt":"2026-04-15T01:27:58","slug":"collar-type-vs-trunk-style-bag-formers-which-one-does-your-machine-need","status":"publish","type":"post","link":"https:\/\/fill-package.com\/vi\/collar-type-vs-trunk-style-bag-formers-which-one-does-your-machine-need\/","title":{"rendered":"Collar-Type vs. Trunk-Style Bag Formers: Which One Does Your Machine Need?"},"content":{"rendered":"

Gi\u1edbi thi\u1ec7u<\/b><\/strong><\/h2>\n

When sourcing a VFFS bag former \u2014 whether you are a machine manufacturer equipping a new line, or a wholesaler restocking spare parts \u2014 the first decision is always collar-type or trunk-style. The wrong choice means the former either cannot handle the product, or the machine runs at a higher rejection rate than it should.<\/p>\n

This guide breaks down the selection decision product by product, so you can make the right call in minutes.<\/p>\n

Not yet familiar with forming sets? Start here: What Is a VFFS Bag Forming Set and How Does It Work?<\/u><\/a>. Or if you are already seeing problems on your line: 5 Signs It’s Time to Replace Your VFFS Bag Former<\/u><\/a>.<\/p>\n

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The Core Difference: Where Product Meets the Bag<\/b><\/strong><\/h2>\n

Both former types do the same job: they turn flat film into a tube. The difference is in how product fills the bag.<\/p>\n

Collar-type: <\/b><\/strong>Product drops from the weigher or filler through the forming tube and falls freely into the bag by gravity. Fast, reliable, and universal for dry products.<\/p>\n

 <\/p>\n

Trunk-style: <\/b><\/strong>The forming tube is extended downward into the bag before filling. Product is delivered near the bag bottom, keeping the upper seal zone completely clear of the product flow. This is critical for powders and liquids, where even a small amount of product contaminating the seal zone causes seal failures.<\/p>\n

 <\/p>\n\n\n\n\n\n\n\n\n\n\n
<\/td>\nCollar-Type<\/b><\/strong><\/td>\nTrunk-Style<\/b><\/strong><\/td>\n<\/tr>\n
Product delivery<\/td>\nTop of bag \u2014 free fall by gravity<\/td>\nNear bag bottom \u2014 via extended tube<\/td>\n<\/tr>\n
Seal contamination risk<\/td>\nLow for dry products<\/td>\nNear-zero \u2014 by design<\/td>\n<\/tr>\n
Primary application<\/td>\nGranules, dry solids, snacks<\/td>\nPowders, liquids, pastes<\/td>\n<\/tr>\n
Film width range<\/td>\n35mm \u2013 800mm<\/td>\n35mm \u2013 800mm<\/td>\n<\/tr>\n
Bag styles<\/td>\nAll standard formats<\/td>\n3-side seal, 4-side seal, stick packs<\/td>\n<\/tr>\n
Teflon options<\/td>\nOuter for film; inner for dust<\/td>\nInner coating is critical<\/td>\n<\/tr>\n
MOQ<\/td>\n1 piece<\/td>\n1 piece<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

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When to Choose the Collar-Type Former<\/b><\/strong><\/h2>\n

The collar-type is the right choice when your product is:<\/p>\n