2. Md. Nazmul Hasan Dipu (2015334034)
Faruk Mia (2015334026)
Group Members
Tanvir Mia (2015334005)
Anup Mondal (2015334015)
Nayan Bhowal (2015334045)
Zihad Islam (2015334055)
5. Definition
Purpose
Locating refers to dimentional and positional relationship
between workpiece and cutting tool used to on the machine.
Locator device to eastablish and maintain position of a part in a
jig or fixture.
โข Positioning the workpiece relative to the workholder
โข Positioning the workholder relative to the cutting tool
โข Producing products to tolerance limits
โข Part fits into the tool in its correct position
โข Restrict the degree of freedom
โข To control chips
โข Maintain position of a part in a jig or fixture
7. Referencing is a dual process of positioning the workpiece relative to the workholder,
and the workholder relative to the cutting tool. Referencing the workholder to the
cutting tool is performed by the guiding or setting devices.
1. Referencing
8. Repeatability is the ability of the workholder to consistently produce parts within
tolerance limits, and is directly related to the referencing capability of the tool.
2. Repeatability
9. The workpieces itself determines the overall size of a locating element.
Locators must be made to suit the MMC (Maximum-Material Condition) of the area to
be located.
3. Accuracy &
Tolerance
10. Ensures that the part fits into the tool in its correct position only. The simplest and most
cost effective method is positioning a fool proof pin.
4. Fool Proofing
11. It involves use of easy , quick and economic loading of workpieces
5. Motion
Economy
12. The final consideration in the placement of locators involves the problem of chip control.
Chips are an inevitable part of any machining operation and must be controlled so they do
not interfere with locating the workpiece in the workholder. Several methods help
minimize the chip problem. First, position the locators away from areas with a high
concentration of chips. If this is not practical, then relieve the locators to reduce the effect
of chips on the location.
6. Controlling
Chips
13. Another condition to avoid in workholder design is redundant, or duplicate, location.
Redundant locators restrict the same degree of freedom more than once.
7. Redundant
Locators
16. Plane locators locate a workpiece from any surface. The surface may be
flat, curved, or have an irregular contour. In most applications, plane-
locating devices locate a part by its external surfaces.
Plane locators locate a workpiece from any surface. The surface may
be flat, curved, or have an irregular contour. In most applications,
plane-locating devices locate a part by its external surfaces.
The third type of location is radial. Radial locators restrict the movement
of a workpiece around a concentric locator.
17. ๏ฑ Good locating provides good dimension and surface of finished products.
So we should concern about appropriate locator to obtain desirable
products. Otherwise, all effort will go in vain.