Hydraulic Systems & Equipment
A Hydraulic Power Unit (HPU) is a self-contained system that generates, controls, and delivers pressurized hydraulic fluid to operate machinery, actuators, or tools. It is the “power source” for hydraulic systems, converting mechanical energy (from an electric motor, diesel engine, or turbine) into hydraulic energy. Main components necessary to operate hydraulic systems, such as pumps, motors, reservoirs, valves, and filters.
Classification Society Certifications (Mandatory)
HPUs must be approved by marine classification societies for offshore use:
- ABS (American Bureau of Shipping) – ABS Rules, Ch.4-8-2 (Hydraulic Systems).
- DNV (Det Norske Veritas) – DNV-ST-0377 (Offshore Hydraulic Systems).
- Lloyd’s Register (LR) – LR Rules for Ships & Offshore Units.
- Bureau Veritas (BV) – BV NR 547 (Hydraulic Systems).
- ClassNK (Japan) – ClassNK Guidelines for HPUs.
General Hydraulic System Standards
- ISO 4413 – Hydraulic system safety & design.
- ISO 13702 – Fire safety for offshore HPUs.
- IEC 60092-504 – Electrical systems in ships/offshore units.
Marine-Specific Standards
- DNV-RU-SHIP Pt.4 Ch.8 – Environmental testing (vibration, shock, humidity).
- IMO MSC.158(78) – Guidelines for vessel control systems.
- SOLAS Ch.II-1 (Regulation 45) – Safety requirements for marine machinery.
American Petroleum Institute standards may apply to offshore HPUs
- API 614 – Lubrication systems including HPUs
- API 674 / 675 – Pump requirements
- API RP 14C – Offshore production safety systems
- API RP 500 / 505 – Hazardous area classification
Hazardous Area Compliance (If Applicable)
- ATEX 2014/34/EU (Zone 1/2) – For HPUs in explosive atmospheres.
- IECEx (IEC 60079) – Global Ex-certification for hazardous zones.
Materials & Corrosion Protection
- ISO 9227 (Salt Spray Test) – 500+ hours for corrosion resistance.
- NORSOK M-501 – Surface treatment for offshore equipment.
Type |
|---|
Electric HPU |
Diesel HPU |
Pneumatic HPU |
Description |
|---|
Compact, quiet, ideal for indoor/fixed systems. |
Portable, no external power needed. |
Uses compressed air to drive hydraulic pumps. |
Use Case |
|---|
Factories, automation. |
Remote sites, offshore. |
Hazardous (Ex) zones. |
Classification Society Certifications (Mandatory)
HPUs must be approved by marine classification societies for offshore use:
ABS (American Bureau of Shipping) – ABS Rules, Ch.4-8-2 (Hydraulic Systems).
DNV (Det Norske Veritas) – DNV-ST-0377 (Offshore Hydraulic Systems).
Lloyd’s Register (LR) – LR Rules for Ships & Offshore Units.
Bureau Veritas (BV) – BV NR 547 (Hydraulic Systems).
ClassNK (Japan) – ClassNK Guidelines for HPUs.
General Hydraulic System Standards
ISO 4413 – Hydraulic system safety & design.
ISO 13702 – Fire safety for offshore HPUs.
IEC 60092-504 – Electrical systems in ships/offshore units.
Marine-Specific Standards
DNV-RU-SHIP Pt.4 Ch.8 – Environmental testing (vibration, shock, humidity).
IMO MSC.158(78) – Guidelines for vessel control systems.
SOLAS Ch.II-1 (Regulation 45) – Safety requirements for marine machinery.
American Petroleum Institute standards may apply to offshore HPUs
API 614 – Lubrication systems including HPUs
API 674 / 675 – Pump requirements
API RP 14C – Offshore production safety systems
API RP 500 / 505 – Hazardous area classification
Hazardous Area Compliance (If Applicable)
ATEX 2014/34/EU (Zone 1/2) – For HPUs in explosive atmospheres.
IECEx (IEC 60079) – Global Ex-certification for hazardous zones.
Materials & Corrosion Protection
ISO 9227 (Salt Spray Test) – 500+ hours for corrosion resistance.
NORSOK M-501 – Surface treatment for offshore equipment.
Test |
|---|
Factory Acceptance Test (FAT) |
Pressure Test |
Flow Test |
Vibration/Shock Test |
Salt Spray Test |
Explosion-Proof Test |
Fire Resistance Test |
Standard |
|---|
ISO 4413 |
1.5x max working pressure |
ISO 4406 |
DNV-RU-SHIP Pt.4 Ch.8 |
ISO 9227 |
ATEX/IECEx |
IMO FTP Code |
Purpose |
|---|
Verifies performance before delivery. |
Checks leaks & burst resistance. |
Validates pump output (GPM/LPM). |
Simulates rough sea conditions. |
Ensures corrosion resistance. |
Required for Zone 1/2 areas. |
Validates flame-retardant materials. |
- Fluid Contamination → Use ISO 4406-compliant filters.
- Overheating → Install coolers and monitor temperature.
- Leaks → Regular maintenance of seals/hoses.
- Use biodegradable or fire-resistant fluids (ISO 6743-4).
- Install remote monitoring (pressure, temp, contamination sensors).
- Conduct regular maintenance (fluid analysis, filter replacement).
- IP Rating – Minimum IP56 (dust/water protection).
- Redundancy – Dual pumps/accumulators for critical systems.
- Material Selection – Stainless steel (316L) or coated carbon steel.
- Cooling System – Air/water heat exchangers for high temps.
- Emergency Shutdown (ESD) – API 14C compliance for oil/gas HPUs.