not saying it is right or wrong... one of the claimed benefits thrown out there years back was that a one piece unit did not have that annular space for salt, sand, etc. to get in and abrade the bladder...
I've had wings returned that had enough salt in them to freeze 5 gallons of ice cream, and I've never once see a bladder damaged by salt. I'd suggest salt damaging a bladder to be a myth.
I still rinse my wings inside and out, as I don't want giant salt crystals inside or sticky OPV's, but I just don't believe salt is a risk to wing bladders.
Tobin
---------- Post added March 3rd, 2015 at 01:32 PM ----------
Two ways to make inflatables; 1) Sewn outer shell with a air tight (typically urethane film bladder) 2) Single layer of fabric with a thin coating of urethane laminated to it.
The first approach is more robust, offers the designer a wider range of choices in shell materials and bladder materials, but is clearly more expensive to produce.
The second method is fast, less expensive, lighter weight and faster drying. It's also less robust, and the choice of laminated materials is far narrower. It is possible to have custom laminates made from pretty much any material and anythickness urethane, however the minimum fabric buy is pretty large. That means most single layer BC's / wings will be made from a pretty short list of "standard" textile / urethane laminates.
Both types can be pinch flatted, but often the single layer wings fail at, or right next to the welded seams, where flexing of the materials eventually causes the urethane to delaminate from the fabric. Welding single layer fabrics can be touchy as the urethane layer is often quite thin and "over sealing" damages the adhesive used to mount the urethane.
Single layer wings can be difficult / impossible to repair if damaged.
Tobin