Safe Use of Hydraulic Systems

Objective:

To know the hazards that could occur from working with hydraulic equipment and how to prevent them.

Trainer's Note:

Many farm implements use a hydraulic system. Understanding the system reduces the chances of having an accident. Ask an experienced worker to demonstrate hooking up farm machinery to the hydraulic system on a tractor. Other workers might practice.

Background

Hydraulic fluid is dangerous. Fluid can escape when adjusting or removing equipment. Fluid can be trapped in the hydraulic system even when the engine and hydraulic pump are stopped. Trapped fluid can be pressurized in excess of 2,000 psi. Pressurized fluid can penetrate the skin, requiring prompt surgical removal. If not properly cared for, gangrene may result. Penetration injuries may not appear serious, but the injected body part is usually lost if medical attention in not promptly sought.

Tighten all connectors before applying pressure. Keep hands and body away from pinholes and nozzles that eject fluid under high pressure. Use a piece of cardboard or paper to search for leaks. Relieve pressure before disconnecting a hydraulic line.

Do not cross hydraulic lines. If the lines are not coupled correctly, the implement will not rise and drop as expected. Tape or color code lines to prevent an accident.

A disconnected implement, in the raised position, has trapped hydraulic fluid that might be pressurized. Heat causes thermal expansion of the fluid, increasing the pressure. Always relieve hydraulic pressure before loosening hydraulic fittings. Injury can result from the hot, high pressure spray of the hydraulic fluid.

Before Servicing a Hydraulic Powered or Controlled Equipment:

• Shut off hydraulic pump power.
• Lower the implement to the ground.
• Move the hydraulic control lever back and forth several times to relieve pressure.
• Follow the instructions in the operator's manual. Specific procedures for servicing hydraulic systems provide safety guidelines.
• Stay away from pinholes and nozzles which eject fluid under pressure.
• Promptly seek medical attention if fluid is injected into the skin.

Review the Following Points

• Adjusting and removing equipment when hydraulic fluid is under pressure can be hazardous.
• Keep all body parts away from pinholes and nozzles which eject fluid under pressure.
• Never cross hydraulic lines on equipment.
• Always lower the implement to the ground before servicing and relieve pressure.
• Follow all instructions in the operator's manual.
• If you notice a lock or a hose in bad condition notify your employer to have it replaced.

Safe Use of Hydraulic Systems Quiz

True or False

1. Escaping, pressurized hydraulic fluid is not a safety concern.	T	F
2. Keep body parts away from pinholes and nozzles which eject fluid under pressure.	T	F
3. It is possible to cross hydraulic lines and have the system work correctly.	T	F
4. If hydraulic fluid is injected into the skin, wash the area immediately and return to work.	T	F
5. Trapped hydraulic fluid can be pressurized to 2,000 psi or more.	T	F

Answer Key
1. F, 2. T, 3. F, 4. F, 5. T

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