Doosan DX60R Shop Manual page 491

Because the volume of oil needed to lengthen the cylinder rod
(Q1) is greater than the volume of oil required to retract the
cylinder rod, it takes more time to decrease cylinder stroke
length than it does to lengthen it.
Q
Q > Q
1 2
Cylinders
2
= S x π(B
Q )
1
4
2- 2
= S x π(B R )
2
4
Figure 3
SP001629
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