Category: Rigging Inspection & Maintenance

Shackle Inspection Checklist: Six Items to Inspect Before Use

Shackle Inspection Checklist: Six Items to Inspect Before Use

Improper use or care of shackles can result in serious accidents that not only injure employees but damage property as well. To avoid this, shackle inspection is critical. In accordance with ASME B30.26, shackles should be visually inspected before every use.

If any of these six conditions are apparent during shackle inspection, the shackle should be discarded and replaced.

Condition 1:

Any part of the shackle is worn more than 10 percent of the original dimensions. If this happens, it typically means that the physical size of the shackle is smaller, therefore it cannot handle the rated load and becomes dangerous to use.

shackle inspection
Example of a Worn Shackle

Condition 2:

The shackle has excessive pitting, corrosion, nicks or gouges. If a shackle has excessive pitting, that is usually a sign of corrosion. When this happens, material is being lost and the shackle dimensionally becomes smaller. Therefore, it cannot handle its rated capacity. Similarly, nicks and gouges are an intrusion on the original dimensions of the shackle and create a stress raiser on the shackle. Material is moved or removed from the shackle, making it smaller in size and unable to handle the rated load.

Condition 3:

Load bearing components are bent, twisted, distorted, stretched, elongated, cracked or broken.

shackle inspection
Example of a Bent Shackle

Condition 4:

Indication of heat damage. When shackles are manufactured, they go through a heat treatment process. Therefore, being exposed to heat in the field can reverse that process and weaken the shackle. Heat damage can be difficult to see, but there are a few key items to look for:

  • Blue or straw discoloration of the shackle material
  • Weld spatter. When weld spatter lands on the shackle, the heat from that molten dot of metal is immediately transferred to the shackle, changing the properties of that shackle.

Condition 5:

Missing or illegible manufacturer’s name or trademark, working load limit or size. Every CM shackle is forged with the CM logo, its body or diameter size, trace code, USA, “Forged” and its specified working load limit. These markings should be visible on the shackle.

Condition 6:

Load pins are bent or have visibly damaged threads. When load pins are bent, the pin has gone past its elastic limit. If the product continues to be used, there is a higher chance of a dropped load, which can injure operators and cause property damage. Damaged threads mean that the pin is not making 100% engagement with the shackle. This can lead to a failure of the shackle.

For more information on shackle inspection and safe shackle use, check out the following:

Nine Important Rules to Follow When Using Shackles
Shackle Markings, Materials, and Appropriate Standards
New CM Shackle Markings and Pins Lead to Improved Operator Safety
Customer Concerns over Recommended Shackle Pin Length

Henry Brozyna

Henry Brozyna is a Corporate Trainer specializing in Rigging & Load Securement for Columbus McKinnon Corporation.

Nine Important Rules to Follow When Using Shackles

Nine Important Rules to Follow When Using Shackles

shackles

Shackles are used every day in a variety of rigging and load securement applications. Before you use a shackle, there are nine important rules to keep in mind.

Rule 1:

When making a sling, attach multiple sling legs to the bow, not the pin. Attaching legs to the pin can damage and weaken the sling.

Rule 2:

When point loading shackle to shackle, connect bow to bow or bow to pin. Never connect pin to pin.

Rule 3:

Do not side load “D” shaped shackles such as chain shackles or long reach shackles. These shackles are designed and rated for in-line applied tension. Therefore, the center line of the load should coincide with the center line of the shackle. Anchor body style shackles (screw pin style, as pictured above, or bolt nut cotter anchor body style) can be side loaded. Always refer to reductions in rating charts when performing this type of rigging.

Rule 4:

When securing a load, the bow of the shackle should be put into the running side of a choke.

Rule 5:

When using a shackle with wire rope, the shackle must be equal to or larger than the wire rope diameter.

Rule 6:

If using a shackle with synthetic slings, ensure the shackle is big enough to avoid pinching or binding the sling.

Rule 7:

Shackles should not be subjected to high or low temperatures that could affect thermal treatment and the strength of the shackle.  -4 degrees F to 400 degrees F is the operating range for full working load limit.

Rule 8:

Always ensure shackle pins are properly engaged. Screw pin shackles need to have threads fully engaged on the shackle ear. (The pin should be flush with the outside of the shackle body or slightly past). The pin head should make contact with the shackle body. Bolt nut and cotter shackles need to have the bolt and nut properly secured with the cotter pin attached.

Rule 9:

Use bolt nut cotter anchor style shackles, if shackles will remain in place as a semi-permanent application or if they will be suspending a load. Screw pin shackles are used when the shackles are removed after the lift is complete. If a screw pin shackle is being used to suspend the load for any length of time, it is advisable that you mouse or tie off the pin to the body of the shackle with wire.
Want to learn more about safe shackle use? Here are some additional resources:

Shackle Markings, Materials and Appropriate Standards
New CM Shackle Markings and Pins Lead to Improved Operator Safety
Customer Concerns over Recommended Shackle Pin Length
Safety Webinar: Proper Use of Shackles 

Last updated on 12/21/15

Christie Lagowski

Christie Lagowski is a Communications Specialist for Columbus McKinnon Corporation.

Are Chain ID Tags Required on Tie-Downs?

Are Chain ID Tags Required on Tie-Downs?

Brad recently asked the following question in response to a blog post The Low-Down on Chain Tie-Downs:

“I wrote to my distributor and inquired about chain tags. Their representative replied that all they had in stock were CHAIN TAGS even though they listed CHAIN and SLING tags made by CM.
They sent me their part number for what I think is a sling tag. Is it okay to use that tag for my Grade 100 chains that I’m using as tie downs? They are not slings, just chains. As I understand it, my Grade 100 chains have to be labeled to prevent a Grade 30 rating by roadside inspectors. Your advice would be appreciated!”

chain ID tags

Henry Brozyna, our Technical Instructor responds:

Thanks for reaching out to us on your question about chain ID tags.

When you contacted your distributor, they automatically assumed that the tag you requested was for a sling (either Grade 80 or 100), which is what prompted them to send you a sling tag. Slings must always be tagged; tie-downs do not.

Inspectors rely on the embossing on the chain to indicate the grade of that tie-down as well as to determine its working load limit. The standard states, that if the embossing is not legible, then the inspector will use the minimum grade for that chain size, which will be Grade 30.

For example: A driver knows his chains are Grade 80. He is using the appropriate number of tie-downs to properly secure the load. At roadside inspection, if the inspector cannot find any legible embossing on the chain, he will apply the Grade 30 rating. With that, the tie-downs can no longer be used. Now, the load does not have sufficient tie-downs to safely secure it during transport.

As for tags, the standard does not require them on tie-down chain, and it would be left to the discretion of the inspector to determine if it’s an acceptable substitution.

Why take the risk? The grade should be legible on the chain if it is being used. If the embossed grade is worn down, the chain should be replaced.
 

Gisela Clark

Gisela Clark is an eMarketing Specialist for Columbus McKinnon Corporation.

Understanding Chain Slings: Why Do Only 3 of 4 Chain Legs Take the Load?

Understanding Chain Slings: Why Do Only 3 of 4 Chain Legs Take the Load?

Randy, an Instrument Technician in the energy industry and recent safety webinar attendee, asks:

“Why do only 3 of 4 chain sling legs take the load?”

Peter Cooke, Columbus McKinnon Training Manager and Safety Webinar Presenter, answers:

understanding chain slings
When using a chain to build a sling, tolerances for chain can make the legs slightly longer or shorter than one another. Because of this, the National Association of Chain Manufacturers (NACM) agreed to only count 3 of the 4 legs of a quad sling to be rated the same. When you first lift the load off the ground the legs that are under tension will stay under tension, so it is important for the rigger to visually see how many legs are loaded before lifting the load off the ground.

To do this, tension up the legs, but do not let the load leave the ground. Safely approach the sling being sure to stay out of the path of tension. You can then quickly check the legs by shacking them slightly. Although you may find all four legs are taking the load, only three are used for calculating the max working load limit of the sling.

It is important to always check the manufacturer’s load charts and safety information prior to making any lift. You must be qualified to lift the load you are rigging.

Want to learn more?

View our Safety Webinar on How to Size Your Chain Slings.
View our blogs on chain sling inspection.

Peter Cooke

Peter Cooke is a Training Manager specializing in Rigging & Load Securement for Columbus McKinnon Corporation.

In-Depth Alloy Chain Sling Inspection Part 5: OSHA Chain Sling Inspection

In-Depth Alloy Chain Sling Inspection Part 5: OSHA Chain Sling Inspection

This article is Part 5 of a 5-part blog series that will cover what professional riggers should consider when performing an in-depth alloy chain sling inspection. Today, we’ll discuss OSHA chain sling inspection regulations and guidelines.

Since first published on July 27, 1975, the OSHA Chain Sling Inspection section has undergone very few changes. These regulations have and continue to serve as a comprehensive guide for those responsible for chain sling inspection.

Chain SlingSpecifically, the applicable sections of the Code of Federal Regulations (29 CFR 1910.184) include:

1910.184(d) Inspections
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. Damaged or defective slings shall be immediately removed from service.

1910.184(e) Alloy steel chain slings

1910.184 (e)(1) Sling identification
Alloy steel chain slings shall have permanently affixed durable identification stating size, grade, rated capacity, and reach.

1910.184(e)(2) Attachments

  • 1910.184(e)(2)(i)
    Hooks, rings, oblong links, pear shaped links, welded or mechanical coupling links or other attachments shall have a rated capacity at least equal to that of the alloy steel chain with which they are used or the sling shall not be used in excess of the rated capacity of the weakest component.
  • 1910.184(e)(2)(ii)
    Makeshift links or fasteners formed from bolts or rods, or other such attachments, shall not be used.

1910.184(e)(3) Inspections

  • 1910.184(e)(3)(i)
    In addition to the inspection required by paragraph (d) of this section, a thorough periodic inspection of alloy steel chain slings in use shall be made on a regular basis, to be determined on the basis of (A) frequency of sling use; (B) severity of service conditions; (C) nature of lifts being made; and (D) experience gained on the service life of slings used in similar circumstances. Such inspections shall in no event be at intervals greater than once every 12 months.
  • 1910.184(e)(3)(ii)
    The employer shall make and maintain a record of the most recent month in which each alloy steel chain sling was thoroughly inspected, and shall make such record available for examination.
  • 1910.184(e)(3)(iii)
    The thorough inspection of alloy steel chain slings shall be performed by a competent person designated by the employer, and shall include a thorough inspection for wear, defective welds, deformation and increase in length. Where such defects or deterioration are present, the sling shall be immediately removed from service.

Please note that while the requirements under (d) for daily inspections are not explicit as to scope or maintenance of records, it is possible that individual OSHA inspectors may have different views on conformity. However, the minimum 12-month interval inspections required under (e) call for thorough inspection and written records. It is this thorough type of inspection that the procedures recommended in our Rigging Catalog and CMCO Training Classes are designed to satisfy.

Of course, the fundamentals are equally applicable to the more cursory daily inspections made by riggers, users or inspectors (individuals deemed a “competent person”) and will enable them to fulfill their responsibility efficiently.

For more information:

 

Peter Cooke

Peter Cooke is a Training Manager specializing in Rigging & Load Securement for Columbus McKinnon Corporation.

In-Depth Alloy Chain Sling Inspection Part 4: Stretch and Chain Elongation

In-Depth Alloy Chain Sling Inspection Part 4: Stretch and Chain Elongation

This article is Part 4 of a 5-part blog series that will cover what professional riggers should consider when performing an in-depth alloy chain sling inspection. Today, we’ll discuss stretch and chain elongation.

Stretched Links
Stretched Links

A visual link-by-link inspection is the best way to detect dangerously stretched alloy chain links. Reach should also be measured from the upper bearing point on the master link to the bearing point on the lower hook. The smallest sign of binding or loss of clearance at the juncture points of a link indicates a collapse in the links’ sides due to stretch. Any amount of stretch indicates overloading, and the chain should be removed from service.

Note that a significant degree of stretch in a few individual links may be hidden by the apparent acceptable length gauge of the overall chain. This highlights the importance of link-by-link inspection.

Alloy steel sling chain typically exhibits well over 20% elongation before rupture. The combination of elongation and high strength provides energy absorption capacity. However, high elongation or stretch, by itself, is not an adequate indicator of shock resistance or general chain quality and should not be relied upon by riggers to provide advance warning of serious overloading and impending failure. Overloading must be prevented before it happens by selection of the proper type and size of slings. Again, any amount of stretch is overloading and the chain should be removed from service.

There is no short-cut method that will disclose all types of chain damage. Safety can only be achieved through proper inspection procedures. There is no adequate substitute for careful link-by-link scrutiny.

Additional Resources:

In-Depth Alloy Chain Sling Inspection Part 1: Twisting & Bending
In-Depth Alloy Chain Sling Inspection Part 2: Nicks and Gouges
In-Depth Alloy Chain Sling Inspection Part 3: Wear & Corrosion

To learn more, view our Chain Sling Inspection Safety Webinar.
Want to get trained? Check out our Qualified Rigger 3 day Workshop.

Peter Cooke

Peter Cooke is a Training Manager specializing in Rigging & Load Securement for Columbus McKinnon Corporation.

In-Depth Alloy Chain Sling Inspection Part 3: Wear and Corrosion

In-Depth Alloy Chain Sling Inspection Part 3: Wear and Corrosion

This article is Part 3 of a 5-part blog series that will cover what professional riggers should consider when performing an in-depth alloy chain sling inspection. Today, we’ll discuss chain wear and corrosion.

chain wear
Figure 1: Inspection for interlink wear can be easily detected by collapsing the chain.

When used in rigorous material handling applications, chain can easily become worn or corroded. It is important to inspect chain for defects on a regular basis to avoid an unsafe lifting condition or even operator injury. When corrosion and wear occur, it results in a reduction of link cross-section which can lead to decreased strength of the chain.

Corrosion can occur anywhere chain comes in contact with harsh chemicals, water or when it is used in tough environments.

Wear can occur in any portion of a link that is subject to contact with another surface.

The natural shape of chain confines wear, for the most part, to only two areas. These are, in order of importance, (a) at the bearing points of interlink contact, and (b) on the outsides of the straight side barrels that may be scraped from dragging chains along hard surfaces or out from under loads.

Figure 1 illustrates the condition of interlink wear and shows how to inspect for it. Notice how easily such wear can be detected by collapsing the chain to separate each link from its neighbors. An operator or inspector can also check for corrosion using the same method.

When chain wear or corrosion is observed, the next step is to determine how severe the damage is and if the chain can still be safely used.

General surface corrosion can be removed by cleaning and oiling the chain. If pitting is observed after cleaning and oiling, remove from service. Next, the operator should take a caliper measurement across the worn section of chain and compare it to the minimum allowable dimension for that chain.

See the chart below for minimum section dimensions or chain wear allowances for Grade 80 and 100 Chain. If the chain does not meet these minimum dimensions, it should be removed from service and replaced.

chain wear

Stay tuned for our next part in this series where we’ll talk about Chain Inspection.

Additional Resources:

In-Depth Alloy Chain Sling Inspection Part 1: Twisting & Bending
In-Depth Alloy Chain Sling Inspection Part 2: Nicks and Gouges

To learn more, view our Chain Sling Inspection Safety Webinar.
Want to get trained? Check out our Qualified Rigger 3 day Workshop.

Peter Cooke

Peter Cooke is a Training Manager specializing in Rigging & Load Securement for Columbus McKinnon Corporation.

In-Depth Alloy Chain Sling Inspection Part 2: Nicks and Gouges

In-Depth Alloy Chain Sling Inspection Part 2: Nicks and Gouges

This article is Part 2 of a 5-part blog series that will cover what professional riggers should consider when performing an in-depth alloy chain sling inspection. Today, we’ll discuss nicks and gouges.

nicks and gouges

When chain is used to lift, pull or secure materials, the outside surface of the links can come in contact with foreign objects that can cause damage. Nicks and gouges frequently occur on the sides of a chain link, which are under compressive stress, reducing their potentially harmful effects.

The unique geometry of a chain link tends to protect tensile stress areas against damage from external causes. Figure 1 shows that these tensile stress areas are on the outside of the link body at the link ends where they are shielded against most damage by the presence of interconnected links.

Tensile stress areas are also located on the insides of the straight barrels, but these surfaces are similarly sheltered by their location. However, gouges can cause localized increases in the link stress and can be harmful if they are located in areas of tensile stress, especially if they are perpendicular to the direction of stress. Refer to Figure 1.

nicks and gouges

Figure 2 shows nicks of varying degrees of severity. Reading clockwise, at three o’clock there is a longitudinal mark in a compressive stress area. Since it is longitudinal and located in a compressive stress area, its effect is mitigated, but good workmanship calls for it to be filed out by hand.

At about five o’clock there is a deep transverse nick in an area of high shear stress. A similar nick is located at six o’clock in the zone of maximum tensile stress. Both of these nicks can create a potentially dangerous escalation of the local stress and must be filed out with careful attention to not damage other parts of the chain link or chain. A nick that was located at eight o’clock has been filed out properly. Although the final cross section is smaller, the link is stronger because the stress riser effect of the notch has been removed. The remaining cross section can now be evaluated for acceptablity by measuring it and applying the criterion for worn chain. See the “Wear Allowances Table” below. 

nicks and gouges

Additional Resources:

Peter Cooke

Peter Cooke is a Training Manager specializing in Rigging & Load Securement for Columbus McKinnon Corporation.

In-Depth Alloy Chain Sling Inspection Part 1: Twisting and Bending

In-Depth Alloy Chain Sling Inspection Part 1: Twisting and Bending

twisting and bending

Twisted and Bent Chain
twisting and bending
D/d is the ratio between the curvature taken by the sling ID and the diameter of the component chain D.

 

 

 

 

 

 

 

 

 

This article is Part 1 of a 5-part blog series that will cover what professional riggers should consider when performing an in-depth alloy chain sling inspection. Today, we’ll discuss the effect of twisting and bending.

Consider that chain is evaluated by applying loads in a pure tensile link end-to-link-end fashion and rated accordingly. Rigging chain around edges or corners alters the normal loading pattern significantly. A lack of proper padding or consideration of the D/d ratio (see above) for chain can result in twisted and bent links. Once a chain is twisted or bent it will alter inner link stresses which can result in failure. For this reason, all chain containing twisted or bent links must be removed from service immediately.

National Association of Chain Manufacturers (NACM), representing domestic manufacturers of welded and weldless chain since 1933, has conducted D/d testing on alloy chain. As a result of this testing, the NACM came out with the chart below which shows reductions in working load limits based on D/d ratio of alloy chain rigged around an edge or a corner. Consult the manufacturer for any D/d below 2. The latest revision ASME B30.9 2014 released for sale this month has adopted this chart into the new standard.

twisting and bending
Using proper sling protection, following the D/d capacity reductions and exercising proper rigging practices will eliminate damage to your alloy chain slings.

To learn more, view our Chain Sling Inspection Safety Webinar.
Want to get trained? Check out our Qualified Rigger 3 day Workshop.

Peter Cooke

Peter Cooke is a Training Manager specializing in Rigging & Load Securement for Columbus McKinnon Corporation.

Advantages of Lifting with Chain Slings vs. Synthetic Slings

Advantages of Lifting with Chain Slings vs. Synthetic Slings

OLYMPUS DIGITAL CAMERA

Overhead Lifting Slings are generally used in conjunction with a crane, powered hoist, manual or lever hoist or some type of lifting device. There are numerous types of materials used for building overhead lifting slings – each with specific advantages and disadvantages – including:

  • Chain
  • Wire rope
  • Synthetics
  • Metal mesh.

Understand the Application Before You Spec a Sling
Before you select a sling it is important to fully understand the application and gather specific information on how the sling will be used. When choosing a sling, you must know the weight, center of gravity, number of attachment points for a balanced lift, sling angles, reach, upper and lower fittings and ambient conditions. Communicate or obtain as much background information as you can about the load being lifted, then decide what type of sling works best. This will help ensure you choose the right sling material and configuration for the task at hand.

Alloy Steel Chain: Recommended by ASME, NACM & OHSA
When using chain slings, the American Society of Mechanical Engineers (ASME), the National Association of Chain Manufacturers (NACM), and the Occupational Safety & Health Administration (OSHA) recommend only the use of alloy steel chain for overhead lifting. Grades 63, 80 and 100 are the alloy steel chains used throughout the industry. They contain elements that give them their unique strength, abrasion resistance, durability and toughness. Per ASTM Standards, alloy chain slings must have the ability to elongate at least 20% when overloaded in order to have a visual indicator to the rigger that the sling is overloaded. Once any stretch is discovered, the chain sling must be removed from service. Synthetics do not have any such indicators as standard.

Advantages of Chain slings versus Synthetic slings

Durability:

  • Resists impact, cuts and abrasions
  • Resistant to chemicals and UV radiation
  • Can be used in oily or dirty environments
  • Can be used at higher temperatures range -40oF thru 400oF with not reduction of WLL (synthetic slings can be used in temperatures no higher than 194oF)
  • Minimum elongation when lifting or tensioning
  • Long service life compared to synthetic slings

Versatility:

  • Easily adjustable (synthetic slings cannot be adjusted and therefore are often used incorrectly)
  • Can be constructed in the field

Inspection & Maintenance:

  • Easy to inspect
  • Completely reparable (cannot repair load bearing fibers in synthetic slings)

139 Years of Chain & Forging Know-How
Columbus McKinnon’s chain manufacturing roots date back to the 1800’s. We hold patents for chain and chain link design as well as the chain manufacturing processes, which help ensure our chain is the strongest and most reliable chain on the market today. We also invented the first alloy chain in 1933 – the forerunner to our industry-changing Herc-Alloy® 800 and 100 chains. In addition to chain, we also manufacture a variety of dual-rated hooks, links, sub-assemblies and other attachments that complement our chain offering.

For additional information on the safe and proper use of chain slings, check out our Safety Webinar on Chain Sling Inspection.

Henry Brozyna

Henry Brozyna is a Corporate Trainer specializing in Rigging & Load Securement for Columbus McKinnon Corporation.