DIE SET:-
The following elements are considered before selecting the die set.
1. Make or manufacture,
2. Type,
3. Size,
4. Material,
5. Thickness of the die holder,
6. Type & length of the bushing,
7. Thickness of the punch holder,
8. Length of guide post,
9. Shank diameter,
10. Grade of precision.
DIE SET COMPONENTS:-
• Top plate.
• Guide bushing.
• Guide pillar.
• Bottom plate.
The following elements are considered before selecting the die set.
1. Make or manufacture,
2. Type,
3. Size,
4. Material,
5. Thickness of the die holder,
6. Type & length of the bushing,
7. Thickness of the punch holder,
8. Length of guide post,
9. Shank diameter,
10. Grade of precision.
DIE SET COMPONENTS:-
• Top plate.
• Guide bushing.
• Guide pillar.
• Bottom plate.
TOP PLATE:-
The upper working member of the die set is called the top plate. The upper surface of the top plate is bears against the under side of the press ram. Punch components are fastened to the lower finished surface. The top plate is generally made out of MS.
PUNCH SHANK:-
The punch shank projects above the top plate and it aligns the centre the die with the centre line of press. In operation the shank is securely clamp to the press ram and it drives the punch portion of the die, rising and lowering the die.
For semi steel die sets, the punch shank is cast integrally with the body of the top plate and it is then machined. To supplement their holding power of the shank, cap screws are often inserted upward to engage tapped in the press ram.
SHANK
BOTTOM PLATE :-
The bottom plate is the lower working member of the die sets. Usually the bottom plate is made thicker than the top plate to compensate the weakening effect of the slug and blank holes which must be machined through it. Generally it is made up of MS.
GUIDE PILLAR:-
Guide pillars are precision-ground pins which are press fitted into accurately bored holes in the bottom plate. They aligns punch & die components with the high degree of accuracy.
Guide pillars are used for precision die sets are chromium plated to provide high degree of accuracy of resistance to wear. The addition of chromium reduce wear up to 50%.
They are specified at least ¼ inch shorter than the shut height.
REMOVABLE GUIDE PILLAR:
Pillars may be removed for die sharpening, specially in large dies.
In first kind of removable pillar have an axial hole machined through them are tapered at one end to engage a taper pin.
In second type of removable pillar, the taper pin is advanced for locking by means of a socket cap screw.
In third type of removable pillar a socket head cap screw is engaged In retaining cap to clamp the pillar to the bushing.
Pillars may be removed for die sharpening, specially in large dies.
In first kind of removable pillar have an axial hole machined through them are tapered at one end to engage a taper pin.
In second type of removable pillar, the taper pin is advanced for locking by means of a socket cap screw.
In third type of removable pillar a socket head cap screw is engaged In retaining cap to clamp the pillar to the bushing.
NON STICKING GUIDE PILLARS:
In initial engagement the jamming of top plate and bottom plate is problem to avoid this kind of problem non sticking pillars are used. Sticking occur until the bushing have engaged the pillars sufficiently for complete alignment.
In initial engagement the jamming of top plate and bottom plate is problem to avoid this kind of problem non sticking pillars are used. Sticking occur until the bushing have engaged the pillars sufficiently for complete alignment.
GUIDE BUSHINGS:
Guide bushings are engaged with the guide pillars for aligning the top plate with the bottom plate. most bushings are made up of tool steel they are also available in bronze.
There are two types :
1.Plain bushing are simple sleeves, pressed into the top plate.
2.Shouldered bushings are turned down at one end and they are pressed into the top plate against the shoulder thus formed.
Guide bushings are engaged with the guide pillars for aligning the top plate with the bottom plate. most bushings are made up of tool steel they are also available in bronze.
There are two types :
1.Plain bushing are simple sleeves, pressed into the top plate.
2.Shouldered bushings are turned down at one end and they are pressed into the top plate against the shoulder thus formed.
BALL BEARING DIE SETS:
Some die sets are provided with ball bearing .Guide pillars are pressed into the top plate and thy engage linear ball bearings.
Lubrication is provided by cup greasing and this is sufficient for entire run. Ball bearings should take more place than conventional guiding and they reduce die space a small extend.
Some die sets are provided with ball bearing .Guide pillars are pressed into the top plate and thy engage linear ball bearings.
Lubrication is provided by cup greasing and this is sufficient for entire run. Ball bearings should take more place than conventional guiding and they reduce die space a small extend.
PILLAR ARRANGEMENT:
Ways of positioning the pillars in a die set.
1.Two pillars are applied at the back of the die sets. This is most commonly used two pillar arrangement.
2.Pillars are applied at the sides force feeding strip from front to back.
3.The pillars are arranged diagonally.
4.Four pillars are used the foregoing are standard pillar arrangement as listed in die set catalogue.
Ways of positioning the pillars in a die set.
1.Two pillars are applied at the back of the die sets. This is most commonly used two pillar arrangement.
2.Pillars are applied at the sides force feeding strip from front to back.
3.The pillars are arranged diagonally.
4.Four pillars are used the foregoing are standard pillar arrangement as listed in die set catalogue.
TWO PILLAR DIE SETS:-
Most tools are provided with two guide pillars applied at the back of the die set because this type gives maximum visibility and accessibility since it is open on three sides.
There are three most distinct type of back pillar die sets.
Regular : This type is employed with average proportions.
Long : This type is used for dies which are long and narrow.
Reverse : This type is used for dies which are relatively longer in measurement from front to back than their measurement from side to side.
THREE PILAR DIE SETS:
It provides increased stability for unbalanced cuts. These are incorporated only in square or rectangular steel sets. For hand feeding, the extra pillar is applied as shone in fig A, at the front. when the feed is automatic it is centered as shown in fig B.
It provides increased stability for unbalanced cuts. These are incorporated only in square or rectangular steel sets. For hand feeding, the extra pillar is applied as shone in fig A, at the front. when the feed is automatic it is centered as shown in fig B.
FOUR PILLAR DIE SET:
These die sets are selected for retaining round disc as drawing tools, trimming tools, and the like. There are two back pillar style as shown in figure A and center pillar style as shone in fig B are available in diameters ranging from 4 to 48 inches.
These die sets are selected for retaining round disc as drawing tools, trimming tools, and the like. There are two back pillar style as shown in figure A and center pillar style as shone in fig B are available in diameters ranging from 4 to 48 inches.
LONG NARROW DIE SETS:
This type of die set is used to retain tools for cutting ,bending and forming of long, narrow parts. they are back pillars sets, and they are available with either two or three pillars. Two pillars are specified for sets ranging from 12 to 72 inches in length and three pillars for sets ranging from 84 to 240 inches.
This type of die set is used to retain tools for cutting ,bending and forming of long, narrow parts. they are back pillars sets, and they are available with either two or three pillars. Two pillars are specified for sets ranging from 12 to 72 inches in length and three pillars for sets ranging from 84 to 240 inches.
ROUND DIE SETS:
Three die sets are selected for retaining round dies such as drawing tools , trimming dies, and the like .There are two back style pillar as shown in fig A and center pillar style as shown in fig B are available in diameters ranging from 4-48 inches.
Three die sets are selected for retaining round dies such as drawing tools , trimming dies, and the like .There are two back style pillar as shown in fig A and center pillar style as shown in fig B are available in diameters ranging from 4-48 inches.
CENTER POST DIE SET:
These die sets are used for secondary operation work such as coining, piercing and left & right hand. Parts of one hand may be conveniently loaded from one side . When the other hand is to be run the die set is turned around 180ºin the press for ease in loading.
FOOL PROOFING:
Center pillar and diagonal pillar die set are provided with different diameter pillars, dimension A and B Thus, the top plate cannot be reversed on the bottom plate.
Center pillar and diagonal pillar die set are provided with different diameter pillars, dimension A and B Thus, the top plate cannot be reversed on the bottom plate.
FLOATING -ADAPTER DIES:
In blanking and piercing thin stock and for shaving and broaching operations very little clearance. can be allowed between the punch and die members. Long should be used with these die sets because, in operation the guide pillar must always be guided within them.
In blanking and piercing thin stock and for shaving and broaching operations very little clearance. can be allowed between the punch and die members. Long should be used with these die sets because, in operation the guide pillar must always be guided within them.
LARGE DIE SET :-
Large die sets are made of plate. They have ground surfaces and are square or rectangular in shape. Three pillars arrangements are shown in fig.
RECOMMENDED THICKNESS:-
The thickness is illustrated in this example.
E.g.
If the die set area for a particular die measures 30 by 20 inches and the force in tons is less than 30, the values of 1 x 3/4th inches for C and 2 inches for D would be selected. However, if the force is in tons were 60, we would use the values opposite pressure in tons of 50-70,and the value for C would be 2½ inches and for D3 inches.
HEAVY DUTY DIE SETS:-
The heavy duty die sets are particularly used for long runs.
They are assembled with removable boss bushings to provide adequate alignment between top & bottom plate.
COMMENTS