Enerpac ST-121 - Manual (Page 3)

Clamping Force -v- Arm Length Graphs
PRELIMINARY INFORMATION
IMPORTANT: Failure to read and follow these instructions may lead to
system malfunction or product failure, and could invalidate your
warranty.
(1) High flow rates can lead to excessive cylinder speed which can cause cylinder
damage. Hydraulic pressure and cylinder speed must be adjusted to match the
length of clamp arm. The clamping force also varies with the length of the clamp
arm. Refer to page 2 for operating specifications.
(2) Flow controls with return checks should be used to reduce swing cylinder speed to
the recommended rate. The return checks help minimize back pressure that could
lead to an unclamp malfunction on single-acting systems.
(3) When using single-acting swing cylinders, limit the return flow back pressure to 50
psi maximum. Large diameter tubing (3/8" O.D. or larger) and flow controls with free
flow return checks help minimize back pressure. Consult Enerpac for proper
system design.
(4) Excessive return flow back pressure can also damage double-acting swing
cylinders. Limit the return flow back pressure to 600 psi maximum. Double-acting
systems should be set up for a metered-in with reverse free flow in the clamp port.
(5) Clamping of the part should occur at the midpoint of the vertical travel. No clamping
of part shall occur while the swing clamp is turning. Clamp arm should freely travel
during the 90° rotation (avoid contact with cutter heads, tools, etc.).
(6) Attaching clamp arm to cylinder plunger must be done according to the instructions
on page 7.
1
1.00
[25]
2.00
[51]
3.00
[76]
4.00
[102]
5.00
[127]
300 [1,33]
2
5
4
0
3
1500 [6,67]
0
1200 [5,34]
900 [4,00]
600 [2,67]
1250 lb (5,6 kN) Models
Max. Clamp Pressure (psi [bar])
5000 [350]
5000 [350]
3800 [262]
1900 [131]
1500 [103]
2500 [172]
Clamping Force (lbs. [kN])
Arm Length (in. [mm])
2600 lb (11,6 kN) Models
6.00
[152,4]
500 [3,3]
0 5.00
[127,0]
2.00
[50,8]
1.00
[25,4]
4.00
[101,6]
3.00
[76,2]
1000 [4,44]
1500 [6,66]
2000 [8,89]
2500 [11,11]
3500 [15,55]
3000 [13,33]
0
5
4
3
2
1
5000 [350]
5000 [350]
3400 [235]
2000 [138]
1700 [117]
2600 [179]
Clamping Force (lbs. [kN])
Arm Length (in. [mm])
Max. Clamp Pressure (psi [bar])
3.00
[76]
.50
[13]
1.00
[25]
1.50
[38]
2.00
[51]
2.50
[64]
150 [0,67]
0
0
1
300 [1,34]
450 [2,00]
600 [2,67]
2
3
4
5
500 lb (2,2 kN) Models
Clamping Force (lbs. [kN])
Arm Length (in. [mm])
5000 [350]
5000 [350]
3000 [207]
2100 [145]
1850 [128]
1550 [107]
Max. Clamp Pressure (psi [bar])
4
3
.50
[13]
1.00
[25]
1.50
[38]
2.00
[51]
2
100 [0,45]
0
0
300 lb (1,3 kN) Models
400 [1,78]
300 [1,34] 1
Clamping Force (lbs. [kN])
Arm Length (in. [mm])
200 [0,89]
5000 [350]
5000 [350]
2500 [172]
2000 [138]
1100 [76]
Max. Clamp Pressure (psi [bar])
3