A correctly selected gasket performs as a key mechano-elastic component in all sorts of industrial applications. Selected according to the following factors, that sealing element absolutely prevents fluid leakage. No matter the pressure, the temperature, or toxicity of that fluid, the properly selected and installed gasket endures. Of course, if we’re to properly establish sealing proficiency, there are some important performance factors to follow, beginning with the fluid’s conveyance characteristics.
Gasket Selection: Assessing Media Characteristics
When we talk about media conveyance, the term is referring to the fluid carried in the pipes. The high or low temperature, the pressure confined inside the conduit, even the caustic nature of that liquid or gas, all of these factors require evaluation. Clearly, if the temperature climbs above 100°C (Water’s boiling point) or below 0°C (Water’s freezing point), certain dynamic media state changes occur. Aggressive steam discharges and layers of expanding ice come to mind, obviously, but these events become complicated by other fluid types and the pressure variances that exist in many industrial processing lines.
Dynamic Loading Effects: The Consequences
Chiefly, then, the gasket materials are subjected to expansion and contraction events. Already compressed by a pair of flanges and a ring of fastening bolts, the factor covered here involves strength and pliability. Mechanical strength gifts the seal with structural integrity, even when the compressible forces reach epic proportions. As for the expansion effect, the durable seal needs a measure of elastic pliability to endure under these conditions. Finally, those baking temperatures and arctic lows will bake or embrittle a gasket if the material isn’t rated as a temperature proficient gasketing substance, so do diligently evaluate this essential criteria effector.
A Study in Gasket Installation Procedures
The selection of a semi-metallic seal or an alloy-corrugated variant also relies on the application area. Is this a heat exchanger vessel? Is the usage domain a pump or valve flange? Then there are the subzero cryogenic and boiler room temperatures to gauge. Finally, when the application and the fluid medium has been accounted for, we address the installation stage. It’s here that the faces of the coupling pipe sections are inspected and cleaned. Certain surrounding equipment assemblies or pipe channels may need to be removed, perhaps due to access considerations.
When the prep work is properly concluded, the gasket is installed. A sealant paste is a potential part of the installation phase, with the compound acting as a corrosion-resistance aid and a seal facilitator. As the opposing flanges come together, ensure they align properly, then add a little lubricant to the face bolts so that the integrity of the joint is assured.
Cracking and drying problems trouble certain elastomeric gaskets. The affliction occurs when the seal dries, becomes brittle, and the material develops hairline fissures. It’s patently obvious here, as these cracks spread, that the gasket has been rendered less than reliable. Unless action is taken, a conveyed fluid will discover the tiny channels and there will be leaks. Here’s a list of tips that are designed to prevent gaskets from cracking and drying.
Low-Pressure Domestic Scenarios
An empty home hibernates. There’s silence in every room, the electricity is turned off, and there’s no water in the pipes. In this residential example, the elastomeric gaskets dry out because they’re unused. Avoid seal cracks by allowing a small trickle to flow. A smart homeowner can also sidestep this issue by asking a neighbour to run the taps occasionally so that the seals are kept wet.
Prevent Ultraviolet Aging
An exposed gasket ages when it’s exposed to UV light. Shield the products by storing the seals in a dark space, not some construction site where they’ll lay under the sun. Better yet, select a gasket material that’s rated to handle ultraviolet light. Incidentally, ozone, another outdoor threat, also causes seal cracking. Ozone occurs naturally, but the otherwise inactive gas is also produced by electrical equipment.
Eliminating Temperature Cycling Cracks
Hot fluids bake elastomers. The constant thermal cycling causes gasket embrittlement. The temperature changes then shrink the product. Bereft of its pliable nature, the seal cracks. Install materials that are rated to endure these temperature extremes. If the conditions are reversed, perhaps by an arctic climate, then the material must be capable of retaining seal integrity when material contraction occurs.
Meeting Mechanical Challenges
Joint expansion and contraction is one thing, but what about vibrational problems? Again, an elastomer that exhibits a matching set of vibration-dampening characteristics is the solution. Reinforce that solution by using a gasket adhesive that incorporates a similarly pliable material base. Additionally, a series of vibration-isolating hoses, as used on hydraulic equipment, will further prevent mechanical noise propagation.
As we can see, many conditions steal gasket pliability. The material hardens, becomes dangerously brittle, then the cracks break out. Prevent gasket cracking and drying by employing the tips we’ve listed above. As for the drying part of this sealing conundrum, a domestic water supply should be kept wet. Otherwise, use a cool, dark area to store the seals, and consider using a paste-like compound as a supplemental gasket lubricating aid.