Wrong material used

Many incidents have occurred because the wrong material of construction was used. This has usually been the result of errors by maintenance or construction personnel or suppliers, who did not use or did not supply the materials specified. Few failures have been the result of errors by materials specialists who incorrectly specified the materials to be used. 

In another incident, on a new plant, two flanged joints leaked an hour after chlorine was introduced. The gaskets were removed and analyzed and were found to be made from titanium although they were stamped Hastelloy, the material specified [5]. 

PTFE gaskets were specified for a section of plant that handled acid. As they ai e fragile and expensive and as an extensive series of tests using water had to be carried out during startup, temporary nitrile rubber gaskets were used during this period. You can guess what happened. One of them was left in position and corroded. 

The manufacturers had provided a test certificate stating that the valve was made from 304L steel. 

The valve was made of Hastelloy, an alloy suitable for use on the unit where it was found but not suitable for use with the mixture of acids on the unit on which it had been installed. 

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Raw materials must be stored in a manner that protects their quality. While it is acceptable to store raw materials outdoors, there are risks that should be recognized. The most pronounced risks are that the container label will become unreadable or that water will enter the container. Because many raw material labels are printed on demand, their labels are often susceptible to degradation by sunlight and water. If the label becomes difficult or impossible to read, an error can be made such as using the wrong material, using an unapproved lot of the proper raw material, or recording an incorrect raw material lot number on the production record. 

Construction. In the constmction phase there are two ways problems can arise. The more common of these is poor workmanship. Uneven foundation settlement and faulty constmction, eg, use of the wrong materials or insufficient quantity of rebars, are but two examples. Only qualified builders, close inspection during constmction, and enforcement of a tightly written specification are necessary factors. 

Usually reactions are carried out without mishaps, but sometimes chemical reactions get out of control because of problems such as using the wrong raw material, using raw materials containing trace impurities, changed operating conditions, unanticipated time delays, equipment failure, or wrong materials of construction. 

Incorrect information can result if the probe is made of the wrong material and is not heat treated in the same way as the process equipment (as well as because of other problems). The probe must be as close as possible to the material from which the equipment of interest is made. Existence of a critical condition, such as weldments or galvanic couples or occluded cells in the eqmpment of concern, makes the fabrication, placement, and maintenance of the probes and monitoring system or critical importance, if accurate and useful data are to be obtained. 

Improper storage, handling, use or disposal of specific chemicals Leakages Improper venting or draining Open handling Incorrect notification on disposal Use of wrong material... 

The hose was made of reinforced rubber, the wrong material. A stainless steel hose should have been used. 

Hoses have failed while tank trucks or cars were being filled or emptied for all the reasons listed in Section 7.1.6, in particular because damaged hoses or hoses made from the wrong material were used. However,... 

First though, we will consider why this is at all a profitable strategy. What is wrong with using helium to cool, and why are lanthanide-based materials of interest to an increasing number of researchers ... 

Use fewer pipe connections to each vessel, reducing the risk of crosscontamination, inadvertent introduction of the wrong material, or the use of the wrong utility. 

This volume of the series Medicinal Plants of the World Chemical Constituents, Modern and Traditional Medicinal Uses contains information on 16 plant species and follows the same format as volumes 1 and 2. Some of the plants discussed in volume 3 may be considered controversial in their classification as medicinal. However, the Paracelsian dictum that sola dosis fecit venenum has been appreciated since ancient times, and throughout the ages many highly toxic materials used for lethal purposes have also found applications in modern medicine. It has been recognized that plants contain substances that are either harmful or toxic. However, it is wrong to think that there are plant toxins that are known or that are likely to have adverse effects on any and every form of life. A common feature of most toxic plants is that they are also known for their curative properties, and although they may provide the cure for an individual s disease at one dose, they may cause the death of the same individual at another. 

While thermal insulations are selected first for their resistance to heal flow, their other properties need evaluation for each application. Hence there is no "best" insulation because a material well suited to one service may be poorly suited to another. Economics must be studied in detail because in some services the cost of a highly efficient material per unit of thickness may be overcome by additional thickness of a less efficient material, provided there is room for the grealet thickness. All properties of materials must he considered for each exposure, even within the same system. Recognize that when different materials are used or different parts nl insulation sv -.tents that arc close together, the probability of using the wrong material on a particular surface is increased appreciably. Unless there is specific reason for wide use ol multiple types of materials, it may be prudent to accept some compromises of properties. 

Most common moisture probes are prone to contamination. The most serious causes of the latter are exposure to CI2, NH3 or wet acids. Common causes of errors in hygrometer readings are too infrequent calibration and the use of the wrong materials for sampling pipework. The allowable concentration of water vapour is so small in some processes that diffusion of water vapour through the walls of... 

The control of chemical reactions is our business. Through the control of reactive chemicals we manufacture nearly all our products. Normally, we carry out these reactions without incident or mishap. However, occasionally chemical reactions have the potential to get out of control because we may use the wrong material, change operating conditions, have unanticipated time delays, have equipment failures, or because we don t always completely understand the chemistry of our process. 

Sometimes maintenance activities can introduce additional hazards. These additional hazards may have an immediate effect, as in the case with providing an ignition source, or a delayed effect, such as what may happen when repairing the equipment with the wrong welding procedures or using repair parts of the wrong materials. 

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