USE OF AIR WINCH PROCESS

 USE OF AIR WINCH PROCESS

What is an Air Winch?

An air winch, also known as an air tugger or air hoist, is a powerful, air-powered machine used for the lifting, pulling, suspension, and tensioning of materials. When properly rated, they can also move personnel between decks, floors, and other areas. In the oil and gas, construction, and maritime industries, air winches are frequently preferred to electric, diesel, and hydraulic winches because of their durability, versatility, and safety.

When Should I Use an Air Winch?

Air winches can fit into spaces and move materials in areas that are unreachable by crane. They are also suitable for areas where fire hazards exist. They have no electrical parts to cause a shock risk, and are fueled by air instead of flammable fuel. Air motors cannot burn out, and can be stalled for long periods without damage. This makes air winches ideal for suspending and tensioning materials. Despite these inherent safety features, they can still pose hazards if safety procedures are not followed properly.

How Do I Choose an Air Winch?

In selecting a specific type of air winch, you should consider job location, the weight and type of load to be moved, mounting site, and wire rope. Follow jurisdictional and company regulations for every particular jobsite. Consider the load as each air winch has a maximum load capacity, known as a maximum rated capacity, which can never be exceeded.

Air winches are categorized as utility, personnel, or dual-rated. Utility winches are rated to move material. Personnel winches, also known as man-riders, are rated to lift, lower, or suspend personnel. Dual-rated winches are rated for both material and personnel, but once used for one of these applications, must exclusively handle that type of load.

What are the Characteristics of a Wire Rope?

The wire rope used by an air winch is comprised of three basic components. First, steel wires form the strands of the wire. Second are the strands themselves, which spiral around the core. Third is the core, which serves as a foundation for the strands.

There are also six characteristics of wire rope:

Size refers to the diameter of the rope, and is always measured at the rope's widest point.

Classification is given as two numbers, representing the strand and wire count. An example would be 6x37, which refers to a rope with 6 strands each made up of 37 wires. Higher wire and strand counts produce more flexible, but less durable ropes.

Rope Lay describes the direction that the wires and strands spiral around the core.

The Grade of Steel of a wire rope will be one of three types: Improved Plow Steel (IPS), Extra Improved Plow Steel (EIPS or XPIS), which is the most commonly used and manufactured grade, or Extra Extra Improved Plow Steel (EEIPS or XXIPS).

There are also three different options for the Type of Core. Fiber core (FC) is made of synthetic material, is the most flexible and elastic, but is susceptible to crushing. Wire strand core (WSC) is made up of an additional strand of wire, is used in smaller ropes, and is ideal for suspension and tensioning. Independent Wire Rope Core (IWRC) contains a smaller wire rope to serve as the core, is highly durable in all environments, and is preferred in offshore and construction environments.

Finally, the nominal strength describes the minimum breaking strength of a new, unused rope.

How Do Air Winches Operate?

Air winches operate using compressed air, usually measured in pounds per square inch gauge, or PSIG. When choosing an air compressor, ensure that its output is compatible with the requirements of the winch. The air compressor's output must equal the winch's air consumption for continuous winch operations.

Most air winches are rated for 90 PSIG inlet pressure when the winch is running. The volume of air required for winch operation is expressed in cubic feet per minute (CFM) or cubic meters per minute (m³/min).

All hoses and fittings must also be compatible with the winch.

How do you Mount / Install an Air Winch?

The mounting site for the winch must be a firm foundation, such as steel support beams, that can withstand five times the maximum load rating of the winch. The mounting site should be as level as possible.

The winch should have a support frame that can be secured to the foundation with heavy bolts or welds. If not, a frame must be attached. Always use the mounting bolts designed for the winch. Never use screws to hold a winch in place. If welding a winch in place, ensure all hot work is done by a qualified welder.

Position the winch so that the operator will have easy access to the hand controls, is always facing the load, and will never be positioned between the load and the winch.

Winch operations should never interfere with other jobs, or be stationed in areas where objects could fall and either injure the operator or damage the winch. Plan the load path so that the load does not travel over, or near, other personnel, workstations, or walkways. In situations where the load must travel over these areas, barricade the load path and post a watch to prevent entry until operations conclude.

Position the airline so that it does not create a tripping hazard, and also label the line so that it is not accidentally disconnected during use.

What is the D/d Ratio and How is it Calculated?

Normal wear occurs each time the rope is used as the wire rope bends around the winch drum or a sheave. The D-to-d ratio accounts for this wear and indicates if a wire rope will be excessively worn or damaged during normal operations. This ratio simply compares the winch drum diameter to the rope diameter.

The D-to-d ratio is calculated by adding the winch drum diameter (D) to the wire rope's size (d) and then dividing the sum by the wire rope size (d).

(D + d)

------

d

For example, if a winch has a 24 inch (D) drum diameter and a 1 inch (d) wire rope is used, the ratio is 25:1.

Higher D-to-d ratios put less stress on the rope. D-to-d ratios which are too low will over-stress and put excessive wear on the rope.

The minimum D-to-d ratio for lifting or lowering a load is 18:1, and the minimum recommended D-to-d ratio for moving personnel is 22:1.

What Are The Steps to Safe Winch Operation?

Safe winch operation helps protect not only those directly involved, but all those at the worksite. Safely operating an air winch can be summarized by completing four simple steps.

The first step of safe winch operation is performing a job safety analysis, or JSA, and obtaining a work permit, if necessary, before the job. A JSA identifies the potential hazards of each winch operation, and then introduces steps to eliminate or reduce these hazards to an acceptable risk level.

The second step of safe winch operation is inspecting the winch and wire rope at the correct intervals. If the winch or wire rope fail any aspect of an inspection, they should not be used.

The third step of safe winch operation is following safe operating guidelines before, during, and after each operation.

The fourth step in safe winch operation is proper winch maintenance performed by authorized personnel. Maintenance helps prolong the life of the winch and helps prevent accidents from occurring.

What are Common Safe Operation Winch Guidelines?

Always ensure that all safe operation guidelines are observed during winch operations.

Common safety rules include:

·         Winch operators must always be qualified and trained

·         Before operations begin, verify that the signal person is visible at all times

·         The operator must focus on the environment and load

·         Ensuring the load never passes near or over personnel or workstations

·         All personnel must stay clear of moving loads at all times

·         Use barricades or designated personnel to prevent entry into the area

·         Only the signal person may relay commands to the operator

·         Anyone may give the emergency stop signal to the operator

How Do You Inspect a Winch?

Performing and documenting regular inspections can uncover problems before a serious accident occurs. If the winch or wire rope fails any aspect of an inspection, they must not be used.

Examine all control mechanisms for any indications of damage or excessive wear.

Inspect all limit switches or limiting devices each shift to ensure they are working properly.

Check for any deterioration or leakage in the compressed air system, including all connections and fittings.

The frequency with which wire ropes should be inspected also depends on the work environment, manner, and how often they are used.

Wire ropes in continuous service must be inspected before the first use, before each shift, or more frequently, depending on work conditions and past experience. To properly inspect wire rope it must be un-reeled.

Check all load attaching equipment and rigging for damage, and ensure the work area is clear and free of debris.

Once all components have passed the inspection, carefully re-spool the rope around the drum. Winch operations can now begin.

Post by Indian Safety Association 

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