Hole Basis system and Shaft Basis System

Hole Basis system: If the system of assembly of shaft and hole is consisting of basic hole, then that type of system is known as Hole Basis System. It means for the system of assembly of shaft and hole, the zero line will be lying on the minimum diameter of the hole as shown figure. For this system the lower limit size of hole is equal...

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Basic Hole and Basic Shaft

Basic Hole: If the lower limit size or minimum size of hole is equal to the basic size then that type of hole is known as basic hole for a given assembly of hole and shaft.   For the basic hole the zero line will be lying on minimum size of the hole. For the Basic Hole the lower deviation is zero because the difference between the...

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Fits and its typs

   Fit is defined as a degree of tightness or looseness between two mating parts to perform definite function when they are assembled together.    A fit may result either in a movable joint or a fixed joint. For example, a shaft running in a bearing can move in relation to it and thus forms a movable joint, where as,...

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Basic terminology for understanding the limits by conventional diagram

  There are various terms are there to understand the limits given to certain objects. These terms are explained by using simple shaft and hole assembly. The following are the terms related to limits.    Basic size: It is a standard size of hole or shaft which is decided during the designing process with which limits are...

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Limits and Fits

   In manufacturing process after manufacturing the product we need to check the dimensions of the product. But any manufacturing process is not perfect to produce the product with exact dimensions means higher accuracy. It means we shall be getting the errors on the dimensions of the product. Some time we shall be getting the dimensions more than the required dimensions and some time we shall be getting dimensions...

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Introduction to Metrology:

        Metrology is a science of measurements. It deals with how to measure the various dimensions of any product and various instruments used for measuring the dimensions. The word Metrology came from the Greek word Metron which means measure. So it is called as Metrology. Metrology deals with all the instruments which are used to measure linear dimensions and non linear dimensions. Examples for linear...

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