FOREWORD
MAINTENANCE STANDARD TERMS
00-12
WA500-6
Repair Limit and Allowable Value or Allowable Dimension
•
The size of a part changes because of wear and deformation while it is used. The limit of changed size is called the
repair limit
.
•
If a part is worn to the repair limit, it must be replaced or repaired.
•
The performance and function of a product lowers while it is used. A value at which the product can be used without
causing a problem is called the
allowable value
or
allowable dimension
.
•
If a product is worn to the allowable value, it must be checked or repaired. Since the permissible value is estimated from
various tests or experiences in most cases, it must be judged after considering the operating condition and customer’s
requirement.
Clearance Limit
•
Parts can be used until the clearance between them is increased to a certain limit. The limit at which those parts cannot be
used is called the
clearance limit
.
•
If the clearance between the parts exceeds the clearance limit, they must be replaced or repaired.
Interference Limit
•
The allowable maximum interference between the hole of a part and the shaft of another part to be assembled is called the
interference
limit
.
•
The interference limit shows the repair limit of the part of smaller tolerance.
•
If the interference between the parts exceeds the interference limit, they must be replaced or repaired.
