Application Layout
Inflatable seals are employed to interact with their surroundings or parts in a variety of different ways. Some seals inflate inwards from their housing or track, others outwards, and others are employed as a face seal. [ SEE EXAMPLE HERE ]
The seal profile and seal shape are critical in defining the limitations as to how small can be fabricated. The inflatable seal layout (stress level, number of seals, etc.) is impacted by how safety or failure critical an application is.

Minimizing Stress
At all times during design, the designer should be trying to minimize stress on the inflatable seal due to high material section property strain, stretch on the material due to over-travel /over-expansion (ensure that a seal always has surfaces to contact against, even in low inflation or low external pressure situations), and proper housing size for the seal, particularly in applications of high frequency inflation.

Plumbing Access
Every inflatable seal at a bare minimum requires a method to inject fluid (air, other gas, liquid) into it to expand it for operation. This point is typically called the inflation port or stem. Inflation ports, stems, or hoses can come in variety of different configurations (pipe connections, compression lock systems, etc.), most customized and bonded integrally to the seal. They can be low profile, small in nature, however, they must be adequately supported against stress at all times. Keep all plumbing lines and connection points out of the range of motion of the process, yet, flexible, when required for dynamic processes.

Customizing Supports / Mounting
Inflatable seals are typically contained in a multi-plate housing or track system. Most housing systems can be bolt mounted, welded, affixed through some other mechanical system, or completely portable, depending upon the application requirements. The goal, as mentioned previously, is to minimize stress and over-expansion of the seal when designing the work setting. Aim for concentric part loading within the inflatable seal design travel range. Never inflate a seal with the target part removed from the seal design setting… the seal can continue to inflate until it bursts or cause damage to it that will shorten its life unpredictably!

Geometry
The shape and size of the inflatable seal cross section plays a large part in how far it can safely expand and how stable it is for performing it’s design function (holding back pressure, lifting a part, etc.). Generally, larger cross sections are preferred for larger seal expansion. If a small envelope is required, custom engineered sealing solutions will have to be employed.

Additionally, overall shape, particularly the corners of rectangular or irregularly shaped seals can cause manufacturing challenges with inflatable seals. The size of a minimum bend radius of a seal is directly tied to the overall cross-section size of the seal… the larger the cross section the larger the minimum bend radius. Sharp corners can be fabricated for many profiles but sealability challenges become complicated at the corners.

Think Outside the Box!
Designing with inflatable seals is extremely innovative and rewarding. Inflatable seals are flexible and can be used for many different operations. When reviewing your strategy to seal or work-position, always try thinking about your problem in the opposite approach. Seals can be fixtures on stationary or remote point of use housings for leak testing. Seals can be placed on crane-operated lifting tools for remote manual operability. Seals can be placed on the doors or door jams. Oftentimes, a little extra thought increases practicality and efficiency in an industrial setting.