EN
AR
CS
DA
NL
FI
FR
DE
EL
IT
JA
KO
NO
PL
PT
RO
RU
ES
SV
TL
IW
ID
LV
SR
SK
VI
HU
MT
TH
TR
FA
MS
GA
CY
IS
KA
UR
LA
TA
MY
The short answer is no — but the reason matters more than the answer. A failed piston rod seal doesn't just leak oil externally; it immediately contaminates the hydraulic circuit with particulate from the scored zone around the rod. Within 20–40 minutes of continued operation, those particles reach the spool valves and percussion accumulator, creating damage that costs 8–12× more to repair than a seal replacement would have. The seal failure is the warning shot. Continued operation is when the real damage happens.
There's a secondary mechanism that gets less attention: piston rod seal failure on one circuit throws the pressure balance off in multi-boom machines. On a three-boom jumbo running at 170–190 bar, a seal failure on Boom 2 drops circuit pressure by 15–25 bar while the other booms continue to draw full flow. The hydraulic pump compensates by over-delivering to the remaining circuits, which runs return temperature up by 8–12°C within 30 minutes. That temperature spike then attacks the seals on Booms 1 and 3. Stopping at first seal failure on one boom prevents a cascade to all three.
Shutdown Decision Matrix After Piston Rod Seal Failure
|
Failure Signal |
Immediate Action |
Why Delay Is Costly |
Time Limit |
|
Oil film visible on rod at end of stroke |
Stop percussion, drain circuit within current shift |
Particulate contamination of spool valves begins within 20 min |
Max 20 minutes additional operation |
|
Pressure drop of 10–15 bar on one circuit |
Stop all booms, isolate failed circuit |
Pump overcorrection raises temperature across all circuits |
Stop immediately |
|
Return oil visibly dark or foamy at sight glass |
Stop, do not restart until circuit is flushed |
Emulsification indicates water ingress — compound failure risk high |
No further operation until flush completed |
|
Rod scoring visible to touch (rough surface) |
Replace rod + seal + inspect bore |
Continued operation scores bore to beyond 0.15 mm — cylinder must be replaced |
No restart until rod replaced |
|
Oil bypass at rod face only, no pressure drop |
Reduce shift to end of current hole, then stop |
Wiper seal failure only — 2–4 hour window before percussion seal affected |
Max one full hole cycle |
The productivity math rarely supports continued operation: an average of 47 minutes of drilling saved by finishing the shift costs an average of 14–18 hours of repair and downtime. HOVOO supplies RD18U, RD22U, and DD2710 piston rod seal assemblies with dimensional verification against OEM specifications. Full references at hovooseal.com.
