Sealing improper

Leaky rotor seals. The rotating rotor seals are very susceptible to leaks. Some of the major causes of seal leaks are nicks or other damage to the seals, improper assembly, and overpressurization. If the culture materials are pumped into the rotor using a positive displacement pump, a blockage (caused by an air bubble, for example) can overpressurize the seal causing it to leak or even rupture. 

Tlie indi ddual cells are assembled into batteries after a leakage test to check for faulty welding joints in steel containers or cracks and improper seals in the plastic encased cells. Cells that are to be delivered without electroltye are emptied after the fomiation cycles. Tlie steel-cased cells hav e to be separated by mechanical means to prevent intercell shorts and are often assembled into wooden crates. Tlie cells in plastic cases can be cemented together or strapped with tape. 

Obviously, oil leakage may be caused by leaking mechanical seals. In turboexpander compressors, however, the most common cause is improperly designed labyrinth seals. Tapered labyrinth designs seem more prone to suffer from this defect. 

Liquid level above seal pan in bottom of column. Poor stripping of bottoms product. High pressure drop across section. Board mounted instrument improperly calibrated. Level gauge in field not properly blown down or even checked. Operation problem. 

Filter media used in dust-collections systems is prone to damage and abrasive wear. Therefore, regular inspection and replacement is needed to ensure continuous, longterm performance. Any damaged, torn, or improperly sealed bags should be removed and replaced. 

One of the more common problems associated with baghouses is improper installation of filter media. Therefore, it is important to follow the instmctions provided by the vendor. If the filter bags are not properly installed and sealed, overall efficiency and effectiveness are significantly reduced. 

Fuel dilution of oil in an engine weakens the oil film strength, sealing ability, and detergency. Improper operation, fuel system leaks, ignition problems, improper timing, or other deficiencies may cause it. Fuel dilution is considered excessive when it reaches a level of 2.5 to 5 per cent. 

Check the thickness of all gaskets against the dimensions shown on the assembly drawing. Improper gasket thickness will affect the seal setting and the spring load imposed on the seal. 

Hoods usually have a light built into a sealed opening, making it explosion-proof for use with flammables. Fans used for flam-mables must also be explosion-proof. Those used for corrosive fumes must be made of material resistant to such fumes. The ductwork must also be corrosion resistant, a matter often overlooked. Built-in exhaust fans make installation and servicing easy, but some tend to be noisy. Remotely installed fans are generally quieter and may serve more than one hood. The chief problem with fans is that they are often improperly serviced. Lubrication and belt tightness must be checked as specified by the manufacturer, or costly repairs will result. 

Improper material of construction or incorrect seal material, etc. in contact with substance... 

Buildup of dirt and other foreign material lodged between the seal ring and seat will create an excessive spin and damage on the floating seal ring unit. It is therefore improper to use soft material such as babbitt and silver as seal rings. 

Test for improperly sealed glass ampoules by immersing in ethanolic methylene blue solution. The dye will penetrate those ampoules which are improperly sealed. 

Liquid polyurethane waterproofing systems are coal-tar modified products. Two-component materials are catalysed curing systems, and one-component materials are cured by exposure to moisture. Both the materials exhibit comparable properties on complete curing. Two-component materials require on-site mixing of the components. One-component materials can be applied directly, but the problem with this type is polymerisation of the product inside the container if it is improperly sealed. Such products are purged with an inert gas when the pack is sealed. 

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