Pasted Valve Stepped End (PVSE)
This style bag is a flat tube with a pasted top and bottom. One corner is left open and a sleeve is placed in that corner for filling. This is the most common multi-wall bag style today. It accounts for more than 70% of the multi-wall bag market. Its characteristics are:
- This style can employ a variety of barrier plies.
- Filled bag has a good palletizing shape.
- This style is not completely sift proof.
- The maximum thickness (bottom size) is 9 inches.
This style bag is used for virtually every type product. However, federal rules and National Freight ruling bodies are reviewing its use for hazardous and nuisance products.
This style bag allows the use of valve packers (air, augers, impeller and belt) in the packaging of dusty and very difficult products. The valve bag provides a means of packaging without the expense of an additional closing operation.
Webb Valve Pinch Bottom (WVPB)
This style bag is a gusseted tube with a pinch closed bottom and a square top with one corner open and a sleeve for filling. This special style bag competes with sewn valve and pinch valve bags where pasted valve stepped in bags do not, since they don`t provide the moisture protection certain products require.
Where this package has been used, it has effectively accomplished the job of improving palletized load shapes. This bag is much easier to spout than the pinch style valve bag offered by others.
Webb Valve Squares (WVS)
This style bag appears identical to the Craighead Valve Bag, but it uses a stepped end tube thus allowing the use of sophisticated barrier plies in the bag.
When this bag is used, it provides a very neat package and pallet-stacking pattern. The Webb Valve Square bag provides a means of fitting a very light product onto a pallet thus allowing truck transit, which may not have been an option otherwise.
Webb Bottom Flush Cut Top (SSWBFC)
This style bag is exactly like the Webb Pinch Top bag except that the top is cut off flush. Customers who were using SOS bags but felt it necessary to graduate to more sophisticated barrier plies than the SOS style can provide use this style. This style can also provide protection from adhesive contamination and contact with paper fibers.
Craighead Valve (CV)
This bag is gusseted tube with square SOS pasted ends. One corner is left open and a sleeve is used for filling. Characteristics of this style are:
- This style bag is the same size empty as it is filled.
- This style is ideal for packing fluffy products. An example would be the carbon black industry using this style to pack fluffy blacks.
- This CV style rectangular bag works well on the vacuum packers where special light products are packed; insuring a firmer, more evenly packed pallet load.
