Checklist of inspections - wire rope on your winch.

[konradh]

DAILY INSPECTION:

Every day you intend or may use the winch, a visual observation of the wire rope should be made. These visual observations should be concerned with discovering gross damage that may be an immediate hazard, such as the following:

1. Rope distortion such as kinking, crushing, unstranding, birdcaging, main strand displacement, or core protrusion

2. Corrosion

3. Broken or cut strands.


MONTHLY INSPECTION:

At the start of the wheeling season, and monthly during the season you should inspect the wire rope for:

1. Reduction of rope diameter below nominal diameter as a result of loss of core support, internal or external corrosion, or wear of outside wires

2. A number of broken outside wires and the degree of distribution or concentration of such broken wires

3. Worn outside wires

4. Corroded or broken wires at end connections

5. Corroded, cracked, bent, worn, or improperly applied end connections

6. Severe kinking, crushing, cutting, or unstranding.

WIRE ROPE REPLACEMENT CRITERIA:

The following criteria determine when a wire rope is no longer acceptable for service:

1. 12 randomly distributed broken wires in one lay or four broken wires in one strand in one lay (A rope lay is that length of rope in which one strand makes one complete revolution about the core)

2. One outer wire broken at the contact point with the core of the rope, which has worked its way out of the rope structure and protrudes or loops out from the rope structure

3. Wear of one-third the original diameter of outside individual wires

4. Kinking, crushing, birdcaging, or any other damage resulting in distortion of the rope structure

5. Evidence of heat damage from any cause

6. Reduction from nominal diameter greater than those listed in the following:

Rope Diameter (inch) Maximum allowable reduction from Nominal Diameter (inch)

Less than or equal to 5/16 1/64
More than 5/16 to 1/2 1/32

Destroy, rather than discard, wire rope to be retired

Wire rope that is not destroyed might be used again by someone not aware of the hazard associated with that use. Destroying wire rope is best done by cutting it up into short pieces.

How to select a rope for winching
All wire ropes feature design characteristic trade-offs. In most cases, a wire rope cannot increase both fatigue resistance and abrasion resistance. For example, when you increase fatigue resistance by selecting a rope with more outer wires, the rope will have less abrasion resistance because of its greater number of smaller outer wires.

When you need wire rope with greater abrasion resistance, one choice is a rope with fewer (and larger) outer wires to reduce the effects of surface wear. But that means the rope's fatigue resistance will decrease. That's why it's important to choose a wire rope the same way any other machine is chosen-very carefully. You must consider all operating conditions and rope characteristics.

So how do you choose the wire rope that's best suited for your job? Consider these seven important characteristics:

1. Strength - Wire rope strength is usually measured in lbs or tons. In published material, the strength is shown as minimum breaking force-calculated strength figures that have been accepted by the wire rope industry.

When placed under tension on a test device, a new rope should break at a figure equal to (or higher than) the minimum breaking force shown for that rope. The minimum breaking force applies to new, unused rope. A rope should never operate at or near the minimum breaking force. The minimum breaking force must be divided by the appropriate design factor to obtain the maximum allowable working load. During its useful life, a rope gradually loses strength due to natural causes such as surface wear and metal fatigue.

2. Fatigue resistance - Fatigue resistance is the rope's resistance to broken wires from metal fatigue. To have high fatigue resistance, ropes must be capable of bending repeatedly under stress (for example, passing over a sheave).

Increased fatigue resistance is achieved in a rope design by using a large number of wires. In general, a rope made of many wires will have greater fatigue resistance than a same-size rope made of fewer, larger wires because smaller wires have greater ability to bend as the rope passes over sheaves or around drums. To overcome the effects of fatigue, ropes must never bend over sheaves or drums with a diameter so small as to bend wires excessively. There are precise recommendations for sheave and drum sizes to properly accommodate all sizes and types of ropes.

Every rope is subject to metal fatigue from bending stress while in operation; therefore, the rope's strength gradually diminishes as the rope is used.

3. Crushing resistance - Crushing is the effect of external pressure on a rope, which damages it by distorting its cross-sectional shape, its strands, or its core. It normally is the result of multiple layer spooling on a drum.

Crushing resistance, defined as a rope's ability to withstand or resist external forces, is a term generally used to express comparison between rope. When a rope is damaged by crushing, wires, strands, and core are prevented from sliding and adjusting normally during operation.

In general, ropes with an independent wire rope core (IWRC) are more crush resistant than fiber core ropes. Regular lay ropes are more crush resistant than lang lay ropes. Six-strand ropes have greater crush resistance than 7-strand, 8-strand, or 19-strand ropes. Compacted strand ropes are more crush resistant than standard round-strand ropes.

4. Resistance to metal loss and deformation - Metal loss refers to the actual wearing away of metal from the outer wires of a rope, and metal deformation is the changing of the shape of outer wires of a rope. In general, resistance to metal loss by abrasion, or abrasion resistance, refers to a rope's ability to withstand metal being worn away along its exterior. This reduces the strength of a rope.

The most common form of metal deformation is generally called peening because outside wires of a peened rope appear to have been hammered along their exposed surface. Peening usually occurs on drums and is caused by rope-to-rope contact during spooling. It may also occur on sheaves.

Peening causes metal fatigue, which in turn may cause wire failure. The hammering-which causes the metal of the wire to flow into a new shape-realigns the grain structure of the metal, thereby affecting its fatigue resistance. The out-of-round shape also impairs wire movement when the rope bends.

5. Stability - The word "stability" is most often used to describe handling and working characteristics of a rope. It is not a precise term because the idea expressed is to some degree a matter of opinion and is more nearly a personality trait than any other rope feature. For example, a rope is referred to as stable when it spools smoothly on and off a drum-or it doesn't tend to tangle when a multi-part reeving system is relaxed.

Strand and rope construction contributes mostly to stability. Preformed rope is usually more stable than non- preformed, and regular lay rope tends to be more stable than lang lay. A rope made of seven-wire strands will usually be more stable than a more complicated construction with many wires per strand. There is no specific measurement of rope stability.

6. Bendability - Bendability relates to a rope's ability to bend easily in an arc. The primary factors that affect this capability are the diameters of wires that make up the rope; rope and strand construction; metal composition and finish; and type of rope core. Some rope constructions are by nature more bendable than others. Small ropes are more bendable than big ones. Fiber core ropes bend more easily than comparable IWRC ropes. As a general rule, rope containing many wires is more bendable than same-size rope made with fewer, larger wires.

7. Reserve strength - Reserve strength is the percentage of a rope's minimum breaking force represented by the inner wires of the outer strands. This recognizes that outer wires should be the first to be damaged or exhibit wear.

Usually, the more wires in each strand of rope, the greater its reserve strength. This is true because of the geometry of a circle: Increasing the number of outer wires in a strand also increases the cross-sectional area occupied by inner wires.

Rotation-resistant rope, due to its construction, can experience different modes of wear and deterioration than standard rope. Therefore, reserve strength is based on the percentage of the metallic area represented by the core strand plus the inner wires of the strands of both the outer and inner layers. Reserve strength is especially important where the consequences of rope failure are great.

[iguana]

Enough Konradh, you are giving too much info in one day