An aircraft engine stand is a tool that is used for mounting an aircraft engine, to make repairs, modifications or perform routine maintenance to an engine. Engine stands come in a number of different types and are suited for a variety of load limits. Most aircraft engine stands allow rotating of the engine so the engine mechanic can have access to all parts of the engine which makes working on hard to reach parts of the engine easier.
Proper maintenance, testing, and repairing of engine stands is critically important to the aviation industry. Inspections should be completed daily or before each use of the engine stand. Periodic inspections of the engine stand should be performed every 6 months and a load test of the stand performed annually.
The Daily Inspections should consist of a visual inspection of the stand for signs of wear. The stand should be clean and properly lubricated.
Mechanical parts, such as bolts, rivets, screw threads, rack teeth, swivel heads, and ram should be checked for cracks or damage which may affect the safe operation of the stand. The ram, any hoses or other hydraulic components should be checked for leaks.
Periodic Inspections involve the inspection of the items for the daily inspection, and also checking for corrosion on the metal parts, inspecting of all welds and joints for cracks, the function of any locking mechanisms, and any other requirements or recommendations as specified in manufacturer or technical manuals. If any external appearance indicates that there may be significant internal issues with any component, that portion of the stand should be taken apart and examined further for internal damage or wear.
Before performing the load test on the engine stand, a functional test is required to ensure that the stand is operating properly. The functional test shall consist at a minimum of lifting a sample load, (normally the typical load that is commonly lifted by the stand), holding the load at a working height for thirty seconds to one minute, moving and/or rotating the load to simulate the operation of the engine stand in the working environment, and lowering the load to its original position. The operation of each of the components of the stand should be smooth and move freely during movement.
After the functional test, a visual inspection should be performed to obtain ‘pretest’ information on the condition of the stand. Use the guidelines for the daily and periodic inspections above for the inspection.
The load test can be performed with a large weight attached to the stand or is more commonly completed using a standard load cell and indicator mounted in the stand to measure the force applied to the stand. The load applied should be at least equal in weight to the heaviest engine weight used for the stand. Larger loads can be used but they must not exceed the manufacturer’s maximum load rating of the stand.
The load test should be performed as follows:
1. Install any test fixtures required for the testing standard you will be using. Place blocks under the stand or lock the wheels as required to ensure that the stand is secure during the test.
2. Mount the testing standard to the engine stand. Secure the testing standard in a way to withstand the force to be applied to the stand.
3. Apply the appropriate load to the engine stand and hold at that force for a minimum of 30 seconds. Release the load. Repeat the load application a second time. Release the load.
4. Perform a visual inspection of all welds, joints and all mechanical components for signs of cracks or other damage from the load test.
5. If the engine stand does not successfully pass the test or any visual defects are found to the mechanical components, the stand or component should be replaced, repaired or returned to the manufacturer for further evaluation.
6. Record the ‘post-test’ findings, test date, and any actions taken for the stand’s permanent records.
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