Predictive Maintenance Technologies Flashcards
7 cards from real CMRT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Predictive Maintenance Technologies flashcards as text
ISO 10816 (or ISO 20816) vibration severity standards categorize machines primarily by:
Answer: Machine power and foundation type (rigid vs. flexible)
ISO 10816/20816 divides machines into groups based on rated power and whether they are mounted on rigid or flexible foundations to assign appropriate velocity alarm limits.
In a PdM program, the 'alert' alarm level is typically set to trigger:
Answer: Increased monitoring frequency and investigation planning
An alert level indicates an abnormal trend requiring closer monitoring and planning of corrective action, but does not require immediate shutdown.
When integrating a PdM program with a CMMS (Computerized Maintenance Management System), the primary benefit is:
Answer: Automatically correlating condition data with work order history and asset records
CMMS integration links PdM findings to asset history, enabling correlation of condition trends with past repairs, parts usage, and work orders for informed decision-making.
A technician notices the vibration trend for a critical pump bearing has doubled over the past 30 days and the spectrum now shows harmonics of the BPFO. The correct action is to:
Answer: Plan a bearing replacement during the next scheduled outage based on remaining P-F interval
BPFO harmonics with a rising trend indicate progressive bearing damage; the correct response is to schedule replacement within the remaining P-F interval before functional failure.
Which factor most directly determines the sampling frequency required when digitizing a vibration signal with an A/D converter?
Answer: The highest frequency of interest, per the Nyquist theorem
The Nyquist theorem requires the sampling rate to be at least twice the highest frequency of interest to avoid aliasing errors in the digitized signal.
Oil analysis identifies a sudden spike in silicon (Si) content in a gearbox sample. The most likely source is:
Answer: Dirt or dust ingestion through a breather or seal
Silicon is an element associated with dirt and environmental contamination; a spike indicates external debris ingestion, often through a failed breather or damaged seal.
The primary purpose of establishing 'baseline' vibration readings when a new machine is commissioned is to:
Answer: Provide a reference for future trend comparison while the machine is known to be in good condition
Baseline readings taken under known good conditions establish a reference signature, making it possible to detect and quantify changes that indicate developing faults over time.