GENERAL Refinery runs and unit operations are planned to meet the anticipated demand for specific products. However. a refinery or operating unit cannot remain in service continuously and still retain its optimum process and mechanical efficiency. Some pieces of equipment@ or parts thereof@ will cease to perform satisfactorily as a result of an accumulation of dirt@ coke@ sludge@ etc. Some items will deteriorate; others will fail or wear out. In order to assure a maximum onstream efficiency@ it is desirable to shut down at predetermined intervals for cleaning. maintenance. and repair. Many inspection operations on major operating equipment must be made while the units are shut down; some other inspections are made preferably while the units are in operation. In order to minimize downtime@ all possible inspection operations should be performed while the units are in operation@ and preparations for inspection of major operating equipment should be made prior to the shutdown .. Inspection which contributes to the maintenance of the desired level of process and mechanical efficiency and augments the safe operation of the refinery equipment is necessary. It should be considered as an aid inbringing about a reduction in the number of process interruptions and in lessening the cost of maintenance and repair. These and other considerations make inspection a vital part of the maintenance program and give. added assurance of a safe@ continuous@ economical operation. Much of the inspection work can be accomplished while the units are onstream or during a short process turnaround. A thorough review of the process flow and operations may reveal that the total inspection of a unit is unnecessary at anyone shutdown. A successful inspection program hinges on the work done in planning future inspections@ knowledge of the deterioration of the equipment and the conditions causing the change@ and ability to work closely with others in the refinery organization. The inspector must have a good understanding of the process operations and a comprehensive knowledge of the equipment@ and he must be able to locate and identify the form of deterioration within the equipment. Information relative to planning an inspection of a new unit can be obtained by consulting the designer or personnel in other refineries which have similar units. Guided by his own knowledge and the experience of others. the inspector should be able to pinpoint the 7 areas which are subject to certain types of deterioration and metal loss. It is desirable that the inspector prepare an inspection procedure or outline. In preparing the outline@ the inspector must exercise sound judgment to determine the extent and type of inspection required for each unit and each piece of equipment. This outline is actually an inspection guide. It should be reviewed@ and possibly revised@ both prior to and immediately following each inspection. Additions or corrections should be made based upon the interim replacements and repairs@ the recommendations resulting from the current inspection@ and the physical changes made during the operating . periods or at the current shutdown. A well-prepared@ detailed procedure informs the inspector what to examine and what the inspection requirements are; it provides assurance that nothing will be overlooked. It enables the inspector to do a better and more thorough job of planning the inspection work. It assists him in the determination of the locations which may require special surface preparation@ tools@ or inspection equipment. Also@ he can better predict the areas wherein the work load is heaviest@ and he can concentrate the inspection effort on these potential trouble spots; thus an extension of the shutdown can be avoided. The success of any inspection program is dependent not only upon the extent of the preliminary and preparatory work@ but on how the actual inspection is conducted and the inspection data obtained. Usually@ the safest way is the most expedient way to inspect. The inspector should make certain that he has provided for his own personal safety and for that of other personnel. He should see that serviceable protective clothing@ tools@ equipment@ and signs are available. (Refer to Chapter V@ Preparation of Equipment for Safe Entry and Work.) Conferences with concerned personnel are valuable in planning for the shutdown inspections.