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FEATURED PRODUCTS - CNC LATHE CHUCK
 
Other Featured Products :Indexing Chuck, Ball Lock Chuck, Hand Operated Chuck, Finger Chuck, Collet Chuck, Pneumatic Chuck, Expanding Mandrel, Lapping Machine
 

power chuck

Power Operated Three Jaw Chuck with Through Bore(PHNC) : GMT Power Operated Hollow High Speed Chucks are designed to rotate at high speeds on CNC lathes. The compact construction of the PHNC Power Chucks offer further advantage of less weight and low inertia which have positive influence on the dynamic effect of CNC machine spindle. These power chucks have a large through bore and are therefore suitable for bar work. The base jaws and top jaws weight are reduced in these chucks. This not only reduces the mass but also lowers the centre of gravity, which make the centrifugal losses low.

Power chucks on CNC machines need to deliver high initial gripping force. GMT takes care of this in the design by making the power chuck operate with a large drawbar pull. Consequently, the wedge is designed to have large contact area with the base jaws. The weight of the body, base jaws and hard jaws are less, without the other essential criteria being sacrificed. The chuck body is recessed to remove a large extent of material to reduce the weight. (from sizes 250 mm to 500 mm). The chuck body is forged steel. The guideways are hardened and ground.

The wedge, made of nickel chrome steel, is case hardened and ground on all the working surfaces. The base jaws also made of nickel chrome steel, are case hardened and ground to match both the wedge and the body guideways. The base jaws are guided in the deep, wide, hardened slots in the body, which provide the ample bearing area necessary to withstand the forces resulting from high gripping action. Provision has been made for manual lubrication of sliding Serrations are ground on the top face of the base. The serrations on the bottom to match the base jaws. The various radii on the hard jaws in conjunction with the serrations are designed to grip a wide range of diameters. hardened chrome case hardened and ground base jaws and the wedge ensure high load carrying capacity over a very long period.

Chuck performance detail
2 Jaw and 4 Jaw chucks with through bore can be offered on request
 
Chuck Size dia
135
165
200
250
315
400
500
Clamping Range
External
Max
128
165
200
250
315
400
500
Min
10
32
25
28
42
45
74
Internal
Max
-
165
200
250
315
400
500
Min
-
62
70
76
84
105
138
Max Drawbar pull (Kgf)
1780
2000
4000
6000
6000
9000
9000
Max gripping force (Kgf)
3670
5400
8000
12000
13000
20000
21000
RPM max
7000
5000
5000
4000
3200
2500
2000
Weight (without top jaws) Kgs.
6
12.5
18
27.5
36
86
164
Flywheel effect GD2 (KPm2)
0.17
0.2
0.38
0.8
2.6
8.4
24.8
Max top jaws weight (per set) Kgs.
0.7
1.5
1.7
3.5
4
7.5
7.5
 
DIMENSIONAL SPECIFICATION
All dimensions in mm
 
Model
04-69
04-70
04-82
04-83
04-84
04-85
04-86
Size dia
135
165
200
250
315
400
500
A dia
135
165
200
250
315
400
500
B dia h7
33
35
48
65
82
120
160
B1
80
90
110
135
155
210
250
C
56
77
85
88
85
120
120
C1
58
82
89
92
92
125
125.5
D Jaw Stroke
2.7
3.15
5.3
5.3
5.3
8
8
E dia H6
110
140
170
220
300
380
380
F
4
5
6
6
6
6
6
G PCD
82.6
104.8
133.4
171.4
235
330.2
330.2
H
3 x M10
6 x M10
3 x M12
3 x M16
3 x M20
3 x M24
6 x M24
H1
M12
M16
M20
M20
M20
M30
M30
H2
M40 x 1.5
M42 x 1.5
M55 x 2
M72 x 2
M92 x 2
M133 x 2
M172 x 3
J
15
14
18
24
31
31
36
J1
43
55
55
55
55
54
54
J2
20
27
28
28
28
28
28
K1 max
-1.8
5
0.5
0.5
3.5
-8.5
-8.5
K2 max
8.2
20
20.5
20.5
23.5
21.5
21.5
N
8.2
15
20
20
20
30
30
O
48
48
62
78
102
142
182
O1
27
30
35
35
35
46
46
S
6
8
8
8
8
12
12
S1
M4
M5
M6
M6
M6
M8
M8
T1 PCD
44
54
68
86
104
145
185
Z1
25
25
30
30
30
30
30
a
41
50.7
59
76
98
118
150
b
23
35
40
45
50
60
60
c min
23.5
28.65
35.7
43.7
54.2
74
92
c max
26.5
31.8
41
49
59.5
82
100
d
M8
M10
M12
M16
M16
M20
M20
e min
6.5
9
9
10
10
15
15
j x 90 degree
1/16"
1/16"
1/16"
1/16"
1/16"
3/32"
3/32"
n
14
19
19
25
25
34
34
n1 max
31
38.5
50
60
85
103
130
q H7
10
12
17
21
21
25.5
25.5
y2
2
3
3.5
3.5
3.5
3.5
3.5
P H12
-
16
16
16
20
20
20
r
M6
M8
M8
M10
M10
M12
M12
m
-
18
23.5
26.5
60
60
115
L
30
36
45
60
60
80
100
V
52
65
80
105
125
155
170
Power Operated Three Jaw Centrifugally Compensated Chuck(PHCNC) : Many CNC machines work at very high speeds. An ordinary, standard power chuck will not work at these speeds because the tremendous centrifugal force generated at these speeds will tend to loosen the job. More importantly, there will be an abrupt and huge loss in the gripping force of the chuck. When there is a loss in gripping power, it will adversely affect the cutting parameters of the lathe. GMT has come up with a chuck designed to take care of the problems arising out of such heavy centrifugal losses. The design is such that the clamping force is very near to that of static clampingforce, even at very high speeds. These centrifugally compensated chucks' share many of the advantageous features of GMT's hollow power chucks. Besides having the above features, the centrifugally compensated chucks have a mechanism whereby the centrifugal losses arising due to very high speeds is compensated. The base jaws are connected to counter weight by means of levers. In result, the centrifugal forces coming on the (a) counter weights, (b) base jaws and hard jaws are compensated or 'nullified' by each other.
 
Guindy Machine Tools Limited - 2010