Film Reveals Pressure Distribution

Article: Hydraulicspneumatics.com

Pressure distribution across a gasketed interface
Pressurex® film shows pressure distribution across a head gasket Color corresponds to magnitude of pressure, revealing areas of high pressure concentration.

Containing a pressurized fluid between mating surfaces without leakage requires the surfacesto be smooth andflat. and with an appropriate gasketin between. Of course, this is no guarantee of leak-free operation. Gaskets can deteriorate overtime, and surfaces can become warped from heat or pitted from corrosion.

After a component has been repaired, it’s always betterto find out if it is leaktight before it is put into service. Several instruments are available to evaluate the flatness of surfaces, but these inspections don’t occurwhen the component is pressurized.

The closest thing to a guarantee may be to use a Pressurex® pressure indicating film from Sensor Products Inc. Madison. NJ. Pressurex® is a thin flexible film that allows quick and easy determination of compression, magnitude, and distribution between two mating surfaces, and because Pressurex® is flexible, surfaces don’t have to be flat – the, can be round or contoured.

Pressurex® has proven success in assessing surface contact inconsistencies in gaskets, clamps, boltedjoints. heatsealing elements, lamination presses, nip rolls, welding heads, clutch and brake assemblies, connectors, and heat sinks. For example. Sensor Products’ ArleneGleicher cited that one user used Presurex® to text the integrity of the crimped union between a hydraulic hose and end fitting.

Pressurex® can also be used in manufacturing operations and for machine and component inspection. Placing a sheet of Pressurex® between dies of a hydraulic or pneumatic press can show whether or not pressure is applied uniformly to all areas of the dies.

Pressurex® film indicates pressure from 2 to 43.200 psi. When placed between two contacting surfaces, the film instantaneously and permanently changes color. This color change correlates directlyto the actual pressure applied. Precise pressure magnitude is easily determined by comparing the resultant color to a color correlation chart. The film comes in the form of a thin Mylar sheet, physically similar in thickness to paper, that conforms to curvaceous surfaces and invasive intolerant environments.