Improper Installation

Void variations due to packing being improperly installed. 

One of the major reasons that this book was written is that nonspecialist chemical engineers know little abont DBAs. Althongh DBAs have been specified and installed for many years, qnite often they have failed becanse the wrong type of flame arrester was specified, or it was improperly installed, or inadeqnate inspection and maintenance were provided. 

Install and test that program. All too often a carefully designed program is improperly installed. There are many facilities that have excellent manuals describing their programs, but these bear no resemblance to what exists in the field. ... 

At initiiil start up, the rate of equipment failure is higli due to factors such as improper installation or problems as a result of defects from the manufacturer. 

More pumps fail as a direct result of improper installation than any other single factor. The predominant reasons for these failures include starvation, caused by inadequate or inconsistent suction conditions distortion, caused by pipe strain or improper foundation and turbulent that results from piping or entrained gas problems. Centrifugal pump installation must follow Hydraulic Institute Standards, which provide specific guidelines to prevent these installation and performance problems. This chapter will address the fundamental requirements for proper installation. 

Many of these chronic problems are the direct result of improper installation. The guidelines provided in this chapter are not all encompassing, but they provide the basic elements that will assure long-term, trouble-free operation of pumping systems. 

While designers can claim some degree of success, there are many occasions when their products are improper installation. 

Piping should easily fit the compressor connections without needing to spring or twist it to fit. It must be supported independently of the compressor and anchored, as necessary, to limit vibration and to prevent expansion strains. Improperly installed piping may distort or pull the compressor s cylinders or casing out of alignment. 

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. 

Most faults are attributed to poorly machined surfaces causing out-of-specification tolerances, although defective material failures also occur. Inadequate material hardness and poor strength factors contribute to many premature failures. Other common causes are improper coupling selection, improper installation, and/or excessive misalignment. 

These efficiencies assume proper, leak-free installation. Filters are often improperly installed and sometimes missing. Reliance on filtration requires a quality-assurance program to ensure that filters are in place and functioning. 

A survey of glazing failures due to wind load indicates that improper installation of setting blocks, gaskets or lateral shims, or poor edge bite is a significant cause of failure because of the resultant unconservative support conditions. To prevent premature glass failure, a strenuous quality control program is required. 

Acceptance testing of fusible link fire dampers should always include a random sample actual fusible link (melting) test of the installed assembly that causes the damper to close. Many times an improperly installed damper will not close correctly and the shutter louvers become hung up or twisted. An alternative sometimes available is a link assembly that can be temporary installed that is easily cut by a pair of clippers. The fusible link melting temperature can then be tested separately at a convenient location without subjecting the installation heat or flames for testing purposes. 

Installation Qualification Installation qualification provides documented evidence that the instrument was received and successfully installed in accordance with the approved design requirements and properly installed in an environment suitable for its operation. Proper installation is the first step to ensure that the instrument will function properly. An improperly installed instrument is likely to cause problems during the operational qualification and performance qualification. The following are some checks for the IQ process ... 

Exterior surface corrosion or rusting of pipes occurs by the formation of iron oxides. Painting to an appropriate specification will significantly extend the period to the onset of corrosion, but the durability of the paint finish is largely dependent on the quality of the surface preparation as well as the thickness of the coated film. Improperly installed insulation can provide ideal conditions for corrosion and should be weatherproofed or otherwise protected from moisture and spills to avoid contact of the wet material on equipment surfaces. Application of an impervious coating such as bitumen to the exterior of the pipes is beneficial in some circumstances. Hypalon and neoprene rubber-based anticorrosive coatings admixed with chlorinated rubber are finding use in many installations. 

Another scenario where large quantities of flammable mixtures may be generated involves slow fuel leaks without ignition in locations where adequate ventilation is not provided. Slow leaks can occur at any of the fittings in the fuel system (from vibration, accident damage, or improper installation or repair), from defective regulators or faulty valves. Low rate fuel releases may be difficult to locate, depending on the rate of fuel release. Their existence will be readily... 

No missing, loose, broken, or improperly installed screws, brackets, or other hardware on the crib or mattress support. 

Almost every discussion on the hazards of plant modifications uses this accident as an example of the need to control plant modifications. The authors, almost without fail, center their attention on the 20-inch (500 mm) diameter piping that was improperly installed to bypass the No. 5 Reactor which had developed a 6-ft.-long crack. But the reason for the crack is usually just briefly mentioned. 

The use of expansion joints (bellows, in this case) which were improperly installed may have been a principal reason for the accident. This provides additional reasons not to use expansion joints (except in special exceptional circumstances). 

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