Norgren NFPA Aluminum & Steel Cylinders - Manual (Page 4)

ACT-1-4 Brookville, OH USA Phone 937-833-4033 www.norgren.com
Series A & EA, NFPA Aluminum Air Cylinders, Impact Dampening Seals
Energy Absorption
Capacity of the Impact
Dampening Seals
The impact-dampening
Piston Seals in the Series EA cylinder
allow for guaranteed, repeatable cushioning.
The compressive qualities of the piston seals are
predictable. The degree of seal compression at
various supply pressures is documented. (See
Energy Absorption Chart.) This allows you to
compute the exact cylinder size required by
knowing the weight (pounds) you are stopping
at a given speed.
Series EA cylinders have a impact dampening
piston seal that accomplishes 80% of the actual
load stopping. The air cushion accounts for only
20%. (A conventional air cushioning cylinder
depends 100% on the compressibility of air to do
the stopping.) The EA seal absorbs high impact
loads allowing the effect of the air cushion to be
reduced by using a larger air cushion bleed
orifice. As a result the piston can move at a faster
speed for a longer period of time before the EA
seal does the final stopping.
See illustration at top of ACT-1-5 for cushion
operation.
3
Norgren Ecology Cylinders offer these advantages:
Norgren Guarantees
Non-lubricated Operation
for a Full Year!
The piston rod is self-lubricated by the
oil-impregnated rod bearing during operation.
Lubrication between piston and cylinder barrel
is derived from the polishing qualities of the
reinforced Teflon
® wear ring.
The low friction surfaces extend the life of the
seals beyond normal expectations, permitting
Norgren to unconditionally guarantee non-
lubricated
operation for one full year. See page ACT-1-98 for
complete warranty.
Series EA cylinders are NFPA interchangeable
and are available in many different mounting styles.
Operates Quietly
to Meet
OSHA Specifications.
Series EA cylinders provide substantial reductions
in impact noise, which reduces overall machine
noise and helps meet government regulations.
The summary of sound decibels chart illustrates the
operating sound levels.
The impact dampening qualities of the
Piston Seals are guaranteed for ONE FULL YEAR!
1 2
Summary of Sound Levels in Decibels
+ Peak sound pressure is given in decibels (dB)
re:2 x 10 5 N/m 2 .
++End position of mike was 3' on centerline from end of
cylinder; side position of mike was 3' perpendicular to
centerline abeam of end of cylinder.
Note: At 5 feet, cylinder sound levels would be less by 9 dB
from side figure and 13 dB from end figure. The total noise
emitted will depend on the structure to which the cylinder is
attached. If it is mounted on a thin flat plate of considerable
area, the noise will be increased by a sounding board effect.
Effect of Impact Dampening Seals on Total Stroke of Cylinders
*The weight of the cylinder piston has been deducted from the figures shown above.
Note: The use of Viton
® Seals limits the absorption of the impact dampening seals by 50%.
Energy Absorption Capacity of the Impact Dampening Seals
*Usable Pounds Stoppable at the Following Piston Speeds
This chart features the energy absorption capacity of the impact dampening piston seals
with Non-Adjustable cushions. For higher loads and velocities please refer to the Decel-Air™ Cushion
Option on ACT-1-10.
Note: These figures are for new cylinders. The impact dampening seals will take some compression set during operation
of the cylinder and the stroke loss will decrease. Also, the pressure at zero stroke loss will decrease to about 80 psi.
At pressures above those of zero stroke loss, a slight clicking sound may be produced during impact.
To determine the stroke loss for either the head or cap end, divide the value shown by 2.
In/Sec
Cylinder Bore
1 1 / 2 2 2 1 / 2 3 1 / 4 4 5 6 7 8
6 155.6 275.5 499.8 969.3 1505.4 2603.2 4159.8 5794.2 8067.6
12 38.4 68.1 123.4 239.7 372.6 644.8 1030.2 1435.8 2000.4
18 16.7 29.7 53.7 104.6 162.8 282.1 450.6 628.7 876.8
24 9.2 16.3 29.4 57.3 89.4 155.2 247.8 346.2 483.6
30 5.6 10.0 18.1 35.4 55.4 96.4 153.9 215.4 301.6
36 3.7 6.7 11.9 23.5 37.0 64.5 102.9 144.4 202.7
42 2.6 4.6 8.2 16.3 25.8 45.3 72.2 101.6 143.1
48 1.8 3.2 5.8 11.7 18.6 32.8 52.2 73.8 104.4
54 1.3 2.4 4.2 8.5 13.6 24.2 38.5 54.7 77.9
60 1.0 1.8 3.0 6.2 10.1 18.1 28.7 41.1 58.9
PSI
Cylinder Bore
1 1 / 2 2 2 1 / 2 3 1 / 4 4 5 6 7 8
0 .14 .15 .17 .19 .22 .25 .28 .32 .32
20 .10 .10 .12 .14 .16 .18 .20 .22 .22
40 .07 .07 .08 .09 .10 .12 .13 .14 .14
60 .04 .04 .05 .05 .06 .07 .07 .08 .08
80 .02 .02 .02 .02 .03 .03 .03 .04 .04
100 0 0 0 0 0 0 0 0 0
PSI Air Sound Cylinder Model
Pressure A133B3 EA155B3 A1133A3 EA1155A3
Level+ 5" x 6" 5" x 6" 2" x 6" 2" x 6"
95 End++ 108 73 110 74
PSI+ Side++ 112 84 110 81
50 End++ 108 73 113 74
PSI+ Side++ 113 85 110 81
In/Sec
Cylinder Bore
1 1 / 2 2 2 1 / 2 3 1 / 4 4 5 6 7 8
6 279 495 899 1,744 2,709 4,685 7,486 10,429 4,520
12 68 122 221 430 699 1,159 1,854 2,583 3,800
18 30 53 95 187 291 507 810 1,130 1,576
24 16 29 52 102 160 279 444 622 869
30 10 18 32 63 99 172 275 387 541
36 6.7 12 21.6 42 66 116 183 259 363
42 4.7 8.3 14.7 29 46 81 129 181 257
48 3.4 5.7 10.4 21 33 59 93 131 187
54 2.3 4.3 7.6 15.3 24 43 68 97 138
60 1.8 3.2 5.4 11 18 33 52 74 106
Energy absorption capacity of the impact dampening
piston seals with an adjustable cushion.