Chain Inspection Criteria

OSHA and ASME safety standards require the user to conduct:

  1. Frequent Inspections: A visual inspection for damage, which should be performed each day the sling is used.
  2. Periodic Inspections: A complete link by link and component inspection. Periodic inspection intervals vary depending on sling usage and conditions, but must occur at least annually. Written records of periodic inspections are required. The slings should be inspected for the presence damage. The sling should immediately be removed from service if any of the following conditions are present:
  • Missing or unreadable identification tag
  • Cracks in the chain or any component
  • Excessive nicks, gouges or wear. Chain should be removed from service if the thickness at any point on the link is below the value shown in the Cam- Alloy Chain Minimum Allowable Thickness chart. All other components should be removed from service if any dimension is worn more than 10% from the original dimension
  • Stretched, bent, twisted, or distorted chain links or components
  • Excessive corrosion
  • Evidence of heat damage
  • Evidence of field welding or weld spatter
  • Any other condition which questions the integrity of the chain sling
  • Any side movement of the Quik Alloy Coupling Link Pin could indicate excessive wear of the pin or link half and be cause for removal from service
  • Depending on the severity of use and environment, individual Quik-Alloy components should be disassembled so that load pins may be thoroughly inspected

Chain Inspection

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Wire Rope Inspection

All wire ropes will wear out eventually and gradually lose work capability throughout their service life. That?s why periodic inspections are critical. Applicable industry standards such as ASME B30.2 for overhead and gantry cranes or federal regulations such as OSHA refer to specific inspection criteria for varied applications.

Three Purposes For Inspection

Regular inspection of wire rope and equipment should be performed for three good reasons:

  • It reveals the rope?s condition and indicates the need for replacement.
  • It can indicate if you?re using the most suitable type of rope.
  • It makes possible the discovery and correction of faults in equipment or operation that can cause costly accelerated rope wear.

How Often

All wire ropes should be thoroughly inspected at regular intervals. The longer it has been in service or the more severe the service, the more thoroughly and frequently it should be inspected. Be sure to maintain records of each inspection

Appoint a Qualified Person To Inspect

Inspections should be carried out by a person who has learned through special training or practical experience what to look for and who knows how to judge the importance of any abnormal conditions they may discover. It is the inspector?s responsibility to obtain and follow the proper inspection criteria for each application inspected.

What to Look For

Here?s what happens when a wire breaks under tensile load exceeding its strength. It?s typically recognized by the ?cup and cone? appearance at the point of failure. The necking down of the wire at the point of failure to form the cup and cone indicates failure has occurred while the wire retained its ductility.

This is a wire with a distinct fatigue break. It?s recognized by the square end perpendicular to the wire. This break was produced by a torsion machine that?s used to measure the ductility. This break is similar to wire failures in the field caused by fatigue.

Shown here is a wire rope that has been subjected to repeated bending over sheaves under normal loads. This results in fatigue breaks in individual wires ? these breaks are square and usually in the crown of the strands.

This is an example of fatigue failure of a wire rope subjected to heavy loads over small sheaves. The breaks in the valleys of the strands are caused by ?strand nicking.? There may be crown breaks, too.

Here you see a single strand removed from a wire rope subjected to strand nicking. This condition is a result of adjacent strands rubbing against one another. While this is normal in a rope?s operation, the nicking can be accentuated by high loads, small sheaves or loss of core support. The ultimate result will be individual wire breaks in the valleys of the strands.

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Wire Rope Sling Inspection

How Often to Inspect

Both AMSE Standard B30.9 and OSHA require that wire ropes receive two types of inspections:

  1. A DAILY VISUAL INSPECTION The person handling the sling must do this each day and should check for major damage or deterioration that would weaken the sling and for obvious signs such as broken wires, kinks, crushing, broken attachments and severe corrosion.
  2. ADDITIONAL INSPECTIONS AT REGULAR INTERVALS These are based on frequency of sling use, severity of service conditions, the nature of the lifts and prior experience based on service life of slings used in similar circumstances. A designated person who has a working knowledge of wire rope must conduct these inspections.

Inspection shall be made at least annually and shall include a record of the inspection or of apparent conditions to provide the basis for a continuing evaluation. Inspection shall be conducted on the entire length of the sling, including splices, end attachments and ttings.

How To Inspect

The following procedures are offered as a guide for conducting inspections:

  1. Place the sling in a position that enables the inspector to access and see every part of the sling.
  2. Clean off all dirt and grease with a wire brush or rags to reveal wires and things.
  3. Examine the entire length of the sling thoroughly, especially the parts showing the most wear.
  4. Pay special attention to ttings and end attachments and areas of the sling next to these ttings.
  5. Find the most worn or damaged section of the sling and carefully check it against removal criteria.
  6. Label or identify all slings you?ve inspected.
  7. Keep records of all inspections, including dates and conditions of slings.
  8. Immediately destroy all slings you?ve rejected.
  9. Store slings you want to reuse in a safe place away from damaging weather, heat and dirt.

When to Replace Your Wire Rope Sling

According to ASME B30.9, you must remove a wire rope sling from service immediately if any of the following conditions are present:

    1. RATED CAPACITY TAG Missing or illegible sling identication tag.
    2. BROKEN WIRES For single part body slings and strand laid grommets: 5 broken wires in one strand in one rope lay or 10 broken wires in all strands in one rope lay. For cable-laid, cable-laid grommets and multi-part slings, use the following guidelines.
      Allowable Broken Wires

      Cable-laid grommet 20 per lay
      Less than 8-part braid 20 per braid
      8-part braid or more 40 per braid
    3. METAL LOSS Wear or scraping of one-third the original diameter of the outside individual wires.
    4. DISTORTION Such as kinking, crushing or birdcaging. Look closely for wires or strands that may have been pushed out of their original positions in the rope.
    5. HEAT DAMAGE Any metallic discoloration or loss of internal lubricant caused by heat exposure.
    6. DAMAGED END ATTACHMENTS Cracked, bent or broken ttings. Also, any evidence that eye splices have slipped, or tucked strands have moved.
    7. BENT HOOKS No more than 15 percent over the normal throat openings (measured at the narrowest point) or twisting exceeding 10 degrees is permitted.
    8. METAL CORROSION Severe corrosion of the rope or end attachments that has caused pitting or binding of wires. Light rusting doesn?t normally affect a sling?s strength.

How to Dispose of a Rejected Wire Rope Sling

Once the inspector has determined a sling is no longer usable, he should tag it immediately, ?Do Not Use.? The sling should then be destroyed as soon as possible by cutting the eye and ttings from the rope. This will prevent accidental reuse of the sling.

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Synthetic Slings

All of our synthetic web products are designed for long life under punishing conditions, but they will eventually wear out after extended use. The key is knowing when to replace them, and that?s why it?s very important to inspect your slings on a regular basis.

We?ve developed an inspection program based on the procedure outlined in ASME B30.9 Slings Standard that will make the most of your investment. It?s based on four sound beliefs:

  • The importance of following regular and uniform inspections.
  • A respect for the capabilities and limitations of synthetic web slings.
  • The need to keep complete, permanent records.
  • Perhaps most importantly, a lot of common sense

How Often to Inspect Slings

The frequency of inspection depends on three important factors:

  1. Sling usage ? the more you use a sling, the more you need to inspect it.
  2. The working environment ? the harsher the conditions, the more often you need to inspect.
  3. Sling service life ? based on your experience in using slings.

It?s a good idea for the person handling the slings to visually inspect all slings before each lift. Additional inspections should be performed at least annually by a qualified designated person and permanent records kept.

OSHA specifies, ?Each day before being used, the sling and all fastenings and attachments shall be inspected for damage or defects by a competent person designated by the employer. Additional inspections shall be performed during sling use, where service conditions warrant.? In other words, you should visually inspect your sling before each lift.

When to Replace Slings

Remove all slings, including Flexi-Grip? round slings, from service if you see damage such as the following, and return to service only when approved by a designated person. These are removal criteria established by ASME B30.9 Slings Standard:

  1. Acid or caustic burns.
  2. Melting or charring of any part of the sling.
  3. Holes, tears, cuts or snags.
  4. Broken or worn stitching in load-bearing splices.
  5. Excessive abrasive wear.
  6. Knots in any part of the sling.
  7. Excessive pitting or corrosion, or cracked, distorted or broken fittings.
  8. Other visible damage that causes doubt as to the strength of the sling.
  9. Missing or illegible sling identification

In addition, we recommend three other important reasons to remove slings from service:

  1. Anytime you see our Red-Guard? warning yarns.
  2. Distortion of the sling.
  3. Anytime a sling is loaded beyond its rated capacity for whatever reason.

While most of these standards are very specific regarding reasons for removal, others require your good judgment. The critical areas to watch are wear to the sling body, the selvage edge of webbing and the condition of the sling eyes.

Our Synthetic Web Products Measure Up.

Our synthetic web products don?t merely meet our own strict standards for workmanship and performance. They also meet or exceed these military and federal specifications:

  1. MIL-W-4088 ? military specification for textile webbing ? woven nylon.
  2. MIL-W-23223B ? military specification for slotted nylon webbing.
  3. Fed. Spec. VT-285F ? federal specification for polyester thread.
  4. Fed. Spec. VT-295E ? federal specification for nylon thread

In addition, all work conforms to standards established by the following national safety institutions and their respective regulations:

ASME B30.9 Slings – American Society of Mechanical Engineers

  • OSHA 1910.184 Standard for Slings
  • OSHA 1926.251 Rigging Equipment for Material Handling
  • WSTDA-RS-1 Roundslings Standard
  • WSTDA-WS-1 Web Slings Standard
  • WSTDA-T-1 Tie-Downs Standard

Identifying Wear and Abuse.

These are some of the most common types of web sling damage caused by abuse and misuse. When you see any of these problems during your regular inspection, stop. Replace the sling immediately because the damage is done. Never attempt to mend the sling yourself and, more so, never attempt to lift with these slings.

Whether a sling is damaged from improper use or normal wear, the same rule applies in all cases: Always cut the sling eyes and discard the sling right away when you see damage. Only with properly working slings can you take a load off your mind.

Tensile Break

Tensile Break

The distinguishing sign of a tensile break is a frayed appearance close to the point of failure or damage. This usually happens when a sling is loaded beyond its existing strength. The photo shows an example of a sling pulled to destruction on a testing machine. You can avoid tensile breaks by never overloading your sling

Cut

Cut Damage

You can easily see a cut in your sling when you see a clean break in the webbing structure or fibers. This can results when a sling contacts a load edges, protrusions and corners, abrasive surfaces or unprotected edge of a load. This can happen anywhere on the sling body or eyes. Many slings feature Red-Guard warning yarns to alert you of serious cuts. One way you can avoid cuts from contacting sharp corners is to use wear pads on the sling to protect the fabric.

Cut and Tensile Damage

 

A good example is the photo shown here. It shows what can happen when you use a sling that?s already been cut by an object along one edge of the sling body. The cut sling should be removed from service, continued use will ultimately lead to sling failure. The solution, obviously, is to never use a sling after it?s been cut.

Abrasion Damage

Abrasion Damage

Anytime you see frayed fibers on the surface exposing the ?picks,? or cross fibers, of the webbing that hold the load-bearing (lengthwise) fibers in place, it?s abrasion damage. The most common abrasion damage occurs either when the sling slips while in contact with a load during a lift or when the sling is pulled from under a load. When you see the Red-Guard warning yarns exposed, it?s your signal that serious damage ? and loss of lifting capacity ? has occurred. We recommend that slings with any damage to load-bearing fibers be discarded. Wear pads are one way to avoid this damage.

Acid Damage

It?s true nylon and polyester webbing are stable when exposed to many common chemicals, but they should never be exposed to any strong acids or corrosive liquids whenever possible. The same is true for metal fittings on slings

Example 1 (top photo). This is what happens when sulfuric acid, like car battery acid, is heated to the boiling point and dropped on nylon webbing. The charring on the surface fibers deteriorates the sling and will continue to get worse, severely affecting the webbing strength.

Example 2 (bottom photo). This is what happens when nylon webbing is immersed in sulfuric acid at room temperature for three weeks, resulting in major damage. Note the fibers are softened and swollen, and the entire fabric is grossly distorted, virtually destroying the webbing. You can help prevent this damage by never storing slings in areas where they may be exposed to acid or acid fumes, which are as destructive as liquid.

When inspecting a web or round sling, it shall be taken out of service immediately and returned for repair or replacement when any of the defects on the right are present.

WEB SLING WARNINGS
Missing or illegible sling identification (tag)
Acid or caustic burn
Melting or charring of any part of the sling
Holes, tears, cuts, abrasive wear, or snags that expose core yarns
Broken or worn stitching in load bearing splices
Excessive abrasive wear
Knots in any part of the sling
Discoloration and brittle or stiff areas on any part of the sling, which may mean chemical or ultraviolet/sunlight damage
Damaged rigging hardware per ASME B30.26
Fittings that are pitted, corroded, cracked, bent, twisted, gouged, or broken
Damaged hooks per ASME B30.10

 

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Twin-Path Slingmax Inspection

NOTE – All incoming slings for inspection and repair in the Twin-Path? department shall be identified with an “Inspection/repair” number (Ex.: TP0001) and entered in a repair log book after inspection.

6.1 Verify that a customer-owned item tag is attached which documents the customer?s name, date received, item description, and reason for return.
6.2 Inspect the sling for the following information on the tag:

  • Serial number (applicable to slings fabricated using Aramid and/or K-Spec filler material)
  • Model number and length
  • Customer unique serial number (as applicable)

6.3 Inspect the sling for any signs of damage according to the most current ASME B30.9 standard and manufacturer recommendations. This shall include any cuts, abrasions, heat damage, missing tell-tails, damaged fiber optics, missing or damaged Check-Fast? inspection System and/or abnormal deformities which shall be identified.
6.4 Should the core yarns be exposed, pull them out through the cover to check their condition. If cut, broken, or showing any damage, the sling is to be rejected and identified. If acceptable, tape over the exposed core yarns and reinsert by pulling on both ends of the sling. 6.5 Mark all cuts or abrasions on the sleeve.
6.6 If applicable, verify that the Tell-Tails extend at least 3 inches beyond the tag area of each sling (at least 5? for slings with a vertical rated capacity of 70,000 lbs. and up or those slings which are 25? long and over). Repairs shall be performed in accordance with step 6.17 of this procedure.
6.7 If applicable, verify that the fiber optic system is operational. (Repairs shall be performed in accordance with step 6.19 of this procedure).
6.8 If applicable, verify that the Check-Fast? Inspection System is not missing or damaged (Repairs shall be performed in accordance with step 6.19 of this procedure).
6.9 Verify that the tag is attached and legible and complies with the most current ASME B30.9 standard. Warnings shall be consistent with the most current verbiage found on the Slingmax? website (www.slingmax.com). (Repairs shall be performed in accordance with step 6.18 of this procedure).
6.10 Document all inspection results on the Inspection and Repair Form
6.11 All slings are required to be proof tested after repairs are performed. If repairs are not required or verification of the slings condition is needed, proof testing should be completed as outlined below.

6.11.1 Verify the current calibration of the test machine. Place the sling to be tested on the machine.
6.11.2 Test the sling in accordance with the applicable test procedure. Take the sling to twice the rated capacity.
6.11.3 Remove the sling from the test machine.

6.12 Document the test results on a test form or computerized test cert.

6.12.1 Document the test in the Pull Test Log Book.

6.13 Place sling in box until a determination of approval for repairs or replacement is received from the customer. Item is to be placed in the customer owned item area.

6.13.1 At the conclusion of the inspection and subsequent documentation on the appropriate forms, the reports shall be signed and dated by the inspector and returned to the office for disposition. A copy of the Inspection and Repair Form may be kept in the Twin-Path Department.
6.13.2 This concludes the inspection process. No further action shall be performed until notified by the office. Notification may include the following options in regards to the inspected sling: Repair, replace, return to customer or destroy.
6.13.3 If the customer wishes to have a rejected item returned to them, a Rejected Item Notification form shall be completed.

6.14 Receive the sales order package from the office. The package shall include the Inspection and Repair Form for the specific items to be repaired.

6.14.1 Confirm the data on the sales order and the customer-owned item tag correctly identify the same customer supplied repair item.

6.15 Perform the repairs identified on inspection form as follows:
6.16 Patches on the outer cover.

6.16.1 Make a patch (using the same material as the outer sleeve) with the appropriate sized Covermax? material.

Note: Single wall tubing (outer cover only) may be used if the repaired area still has the inner cover intact. Otherwise standard double-wall Covermax? shall be used.

6.16.2 Place the patch over the area to be repaired. Sew the along the entire length of the patch. The patch should be sewn inside out to hide the stitching and turned right side out over the repair area. Slingmax Technical Bulletin 44 should be referenced.

NOTE – Thread – The thread which is used to sew the sling covers and tag shall be fully compliant with the most current WSTDA-TH-1 standard (with the exception of Sparkeater Slings which is Aramid). Stitching – All stitches shall be lock-stitched and preferably continuous. When the stitching is not continuous, it shall be back-stitched or overstitched to prevent unraveling.

6.16.3 Stitch the patch ensuring to avoid penetrating the core yarns.

6.17Repairs to the Tell-Tails.

6.17.1 Pull the existing tell-tails out of the sleeves at least to the end of the taped portion. If the tell-tails have pulled in past the tag area, locate the tell-tail end and extract it from the sling.
Note: If the tell-tail cannot be located, remove the stitches which secure the cover where it overlaps. Pull the cover back until the core strands are exposed and the tell-tail(s) is located.
6.17.2 Using the same material and number of strands of core yarn cut an appropriate length for each tell-tail. Tie the new tell-tail material to the old tell-tail (below the taped portion) using a fisherman?s knot.
6.17.3 Cut off the taped portion of the old tell-tails.
6.17.4 Using manufacturer?s identification tape, tape the new tell-tails over the knots and to the end of the new material.

6.18 Replacement of the tag.

6.18.1 Mark the location of the cover material seam overlap.
6.18.2 Remove the tag by removing the stitches which secure the tag to the sling. Care shall be taken to avoid damage to the sling.
6.18.3 Select the correct identification and warning tags for the sling. Tags shall meet or exceed the requirements of the most current ASME B30.9 standard (ex. Must have manufacturers name, core material, manufacturer?s code or stock number, rated loads for the types of hitches used and the angle upon which it is based and cover material.) Warning tag(s) shall be consistent with the most current verbiage found on the Slingmax? website (www.slingmax.com)

NOTE: All high performance fiber filled slings require a serial number be selected from the log book and written on the tag consisting of the facility, date and sling serial number (example: P042418001). For increased traceability, it is recommended that this information also be written on the back of the tag, on the side of which it will be inserted into the sling.

6.18.4 Ensure the repair agent is identified on the tag.
6.18.5 Sew the tag onto the sling by stitching on the centerline ensuring that stitches do not penetrate the core strands.
6.18.6 Remove any loose threads.
6.19 Replacement of the fiber optic system.
6.19.1 Mark the location of the cover material seam overlap.
6.19.2 Remove the tag by removing the stitches which secure the tag to the sling. Care shall be taken to avoid damage to the cover material.
6.19.3 Remove the stitches securing the sling overlap. Remove the remainder of the stitches to allow the cover to be pulled back 40? enabling access to the filler core strands.
6.19.4 Remove the tape which separates the strand paths.
6.19.5 Pull out the damaged fiber optic cable.
6.19.6 Position the tail stock at the appropriate position as determined by the sling length. Tighten the tail stock.
6.19.7 Using locking pliers or other suitable tool, clamp the end of the cover with the long (40?) rolled back cuff to the cross bar.

6.19.7.1 Loop the remaining cover material around the tail stock.

6.19.8 Insert the end of the replacement fiber optic cable into the path which originally had the fiber optic. Form a loop with the fiber optic cable leaving a 10? tail and tape into place.
6.19.9 Jog the fiber optic cable into the cover until the original loop is located at the drive roller.
6.19.10 Remove the tape from the fiber optic cable.
6.19.11 Using manufacturer identifying tape, bundle and tape the core strands. Starting at the 40? cuff, tape the two individual paths of the core material up to the opposite end of the sling.
6.19.12 Insert a metal probe through the previously placed fiber optic access hole. Insert the end of the fiber optic cable through the probe. Guiding the fiber optic cable, pull the probe and the fiber optic cable through the hole.
6.19.13 Roll the cover material over the exposed core. Ensure that the original marks placed instep 6.19.1 line up. Remove the sling from the fabricating machine.
6.19.14 Follow the steps shown in 6.19 for the replacement of the tag.

6.20 Replacement of the Check-Fast? Inspection System

6.20.1 Mark the location of the cover material seam overlap.
6.20.2 Remove the tag by removing the stitches which secure the tag to the sling. Care shall be taken to avoid damage to the cover material.
6.20.3 Remove the stitches securing the sling overlap. Remove the remainder of the stitches to allow the cover to be pulled back 40? enabling access to the filler core strands.
6.20.4 Remove the tape which separates the strand paths.
6.20.5 Locate and remove the damaged weak link and EWI.
6.20.6 Remove waterproof tape and leader yarn holding the sacrificial strand to the core yarn bundle.
Note: Do not remove or replace the sacrificial strand. If it is damaged the sling must be rejected.
6.20.7 Refer to TP-I-11 to reinstall the Check-Fast? System.
6.20.8 Roll the cover material over the exposed core. Ensure that the original marks placed in step 6.20.1 line up. Remove the sling from the fabricating machine.
6.20.9 Follow the steps shown in 6.18 for the replacement of the tag.

6.21 Perform the second person inspection. Inspect for the following:

  • Sling repairs are correct per the Inspection and Repair Form.
  • Patch(s) are correctly stitched and do not penetrate the core yarns.
  • Tell-Tails are properly taped and are the correct length.
  • Information on the tag is correct.
  • Stitching is correct and does not penetrate the core yarn.
  • Fiber optics are correctly working
  • Check-Fast? Inspection System is installed correctly.

6.21.1 Document this inspection.

6.22 The non-conformance (NCR) process shall be initiated, if during the repair and inspection process, new deficiencies occur which cannot be corrected easily and quickly to bring the product into conformance.
6.23 Completed slings should be rolled or folded and individually packed in a polyethylene bag when possible. Insert appropriate literature including the warning/instruction sheets. Bagged slings should then be packed and sealed in an appropriate sized container for shipping. The outer container shall be stamped ?Opening Box with Sharp Tool May Cut and Damage Contents?.
6.24 Verify that the sales order package is documented as required and return the completed package to the office.

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