Chain 101

Chain

CHAIN 101

Welcome to Advantage University’s Chain 101 class. Chain 101 has been designed to help you gain basic knowledge in the world of Chain. In this class, you will learn the following:

  • Chain Grades and Identification
  • Basic Chain Terminology
  • A Brief Introduction to Chain Inspection

IMPORTANT DISTINCTION:  It is CRITICAL that you learn to discern between Chain that IS OSHA Approved for Overhead Lifting and Chain that IS NOT OSHA Approved for Overhead Lifting.

READ THIS: Before we begin, to use, sell or select chain properly, you must learn the difference between chains that ARE OSHA  approved for Overhead Lifting (OHL) by the Occupational Health and Safety Administration(OSHA)  , and chains that ARE NOT OSHA approved for OHL. According to OSHA and the National Association of Chain Manufacturers (NACM), the only chain grades that are rated for OHL are Grade 80, Grade 100 & Grade 120.  All other grades ARE NOT approved by OSHA for OHL. It is considered an Overheard Lift when the load lifts off the ground or lifts off the object it is resting upon. OSHA makes no distinction between an injury to a toe or an injury to a head.  OSHA’s goal is to eliminate all injuries.  Therefore, the term “Overhead Lifting” is a misnomer.  It does not have to be lifted above one’s head for the term “Overhead Lifting” to apply.

Let’s Talk About Chain, Shall We?

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Chapter 1: Chain Grades, Finishes & Identification

SECTION 1: CHAINS THAT ARE NOT RATED FOR OVERHEAD LIFTING

Grade 30 – Proof Coil (also referred to as proof chain, grade 28, System 3 and Grade 3)

  • Grade 30 Proof Coil IS NOT RATED for OVERHEAD LIFTING by OSHA
  • Grade 30 Proof Coil Markings – Grade 30 can be marked 28, 3, 30 or simply have no markings at all. There may be a letter before the number (like D3 or D30) which is usually a manufacturer’s ID code. Made from Low Carbon Steel (except for stainless steel)
  • Grade 30 Proof Coil Proof Coil – Surface Finishes
    • Self-Colored – also known as SC or ungalvanized. Self-Colored is simply plain unfinished steel which provides no rust proofing)
    • Zinc Plated (otherwise known as ZP, EG or Electro Galvanized which provides a modest rustproofing but is shiny and is great for retail)
    • Hot Dip Galvanized (otherwise known as HDG or Hot Galvanized and provides the best rust proof coating of the three)
    • Powder Coated (Yellow, Black or Blue are stock here ate Advantage between 3/16-3/8)S
    • Stainless Steel Proof Coil – While technically unfinished it is a highly corrosion resistant material. Available in Type 304 or Type 316
  • Grade 30 Proof Coil Common Uses – trailer chains, lock chain, crowd control, general use that is not critical in nature or for OHL.  Stainless Steel Proof Coil is used in chemical, nuclear, wastewater, marine and other corrosive environments.

Grade 43 – High Test (also referred to as Grade 40, System 4 or Grade 4)

  • Grade 43 High Test Chain IS NOT RATED for OVERHEAD LIFTING by OSHA
  • Grade 43 High Test Markings – Grade 43 can be marked 4, 40, 43, G4, G43 or simply have anything with a 4 embossed on the link. There may be a letter before the number (like D4 or D43) which is usually a manufacturer’s ID code.
  • Grade 43 High Test – Surface Finishes
    • Self-Colored – also known as SC or ungalvanized. Self-Colored is simply plain unfinished steel, which provides no rust proofing
    • Zinc Plated (otherwise known as ZP, EG or Electro Galvanized which provides a modest rustproofing but is shiny and is great for retail)
    • Hot Dip Galvanized (otherwise known as HDG or Hot Galvanized and provides the best rust proof coating of the three)
    • Stainless Steel High Test – While technically unfinished it is a highly corrosion resistant material. Available in Type 304 or Type 316
  • Grade 43 High Test Common Uses – trailer chains, lock chain, agriculture general use that is not critical in nature or for OHL. Stainless Steel High Test is used in chemical, nuclear, wastewater, marine and other corrosive industrial environments.

 

Grade 70-Transport (also referred to as Transport Chain, Grade 7, System 7 or Gold Chain, Binder Chain or Boomer Chain)

  • Grade 70 Transport Chain IS NOT RATED for OVERHEAD LIFTING by OSHA
  • Grade 70 Transport Markings – Grade 70 Transport can be marked 7, 70, or simply have anything with a 7 embossed on the link. There may be a letter before the number (like D7 or D70) which is usually a manufacturer’s ID code.
  • Grade 70 Transport – Surface Finish
    • Grade 70 Transport Chain usually colored Gold. Technically, the finish is referred to as Yellow Dichromate or Yellow Zinc
    • The Gold finish is helpful to law enforcement. When examining trucks/trailers for safety, the gold color helps them see that the user is using Grade 70.
  • Grade 70 Transport Chain Common Uses – Grade 70 Chain is used for 3 main purposes: 1) For Use with GOLD-TIP Load Binders for Cargo Control use on DOT controlled (Federal Interstate or State) roadways 2) Trailer Safety Chains for heavier travel trailers, utility trailers, horse trailers etc. that are chained to the vehicle for safety and 3) pulling objects which are stuck.  Grade 70 is the lowest grade allowable on the interstate highway system.
  • Grade 70 Transport Chain is typically provided in 2 ways 1) in Bulk or 2) in the form of a “Binder Chain” or “Boomer Chain”. A “Binder Chain” is a chain that has been cut to a standard length (usually 10’, 12’ 16’, 20’ or 25’) and generally has Grade 70 Grab Hooks on each end.  The lowest chain grade hooks allowed for use with Grade 70 chain are Grade 70 Hooks.  High Test Hooks are not compliant.

Specialty Chain – often referred to as “junk chain” because of its low working loads and non-critical nature.

  • Specialty Chain IS NOT RATED for OVERHEAD LIFTING by OSHA
  • Markings – Generally, there are no distinguishing markings on specialty chain
  • Types of Specialty Chain
    • Double Loop (AKA Tenso Chain or Well Chain)
    • Sash
    • Single Jack
    • Straight Link Coil
    • Twist Link Machine
    • Passing Link
    • There are many other styles, finishes (SC, ZP, HDG, Powder Coated) and materials (Mild Steel or Stainless) available
  • Specialty Chain Common Uses – any application not requiring high working loads.

SECTION 2: CHAINS THAT ARE RATED FOR OVERHEAD LIFTING (OHL)

Grade 80 Alloy Chain (also referred to as Grade 8, System 8, Lifting Chains or Alloy Chain)

  • Grade 80 Alloy Chain IS RATED for OVERHEAD LIFTING
  • Grade 80 Alloy Markings – Grade 80 can be marked 8, 80, or simply may have anything with an 8 or 80 embossed on the link. There may be a letter before the number (like D8 or D80) which is usually a manufacturer’s ID code.
  • Grade 80 Alloy – Surface Finish
    • Here at Advantage, our Grade 80 Alloy Chain is Black Lacquer Finish. Finishes vary by supplier.  It is very common to see Grade 80 Alloy Chain be Self Colored (no rust-proofing) as well.
  • Grade 80 Alloy Common Uses
    • Grade 80 Chain is primarily used in Overhead Lifting (OHL) applications or high strength requirement applications such as Heavy Vehicle Recovery, pulling excavation equipment from mud, etc. A fabricated rigging product, known as a Chain Sling, is fabricated and inspected by a qualified individual, using products engineered for the agreed upon application.  There are many different Chain Sling configurations.  Each Grade 80 Chain Sling has a unique rating that coincides with the grade and configuration.  Rigging training is required when using Certified Chain Slings.  It is required that Grade 80 Hooks and Components be used on Grade 80 Certified Chain Slings in order to maintain its Safe Working Load rating.  Using components such as hooks that are Graded below Grade 80 (such as a Grade 70 hook), shall make the Chain Sling out of compliance with OSHA Standards.
    • Grade 80 is approved by USDOT for use in Cargo Control on Interstate Highways

 

Grade 100 Alloy Chain (also referred to as Grade 10, System 10, Lifting Chains or Alloy Chain)

  • Grade 100 Alloy Chain IS RATED for OVERHEAD LIFTING
  • Grade 100 Alloy Markings – Grade 100 can be marked 10, 100, or simply may have anything with a 10 or 100 embossed on the link. There may be a letter before the number (like D10 or D100) which is usually a manufacturer’s ID code.
  • Grade 100 Alloy – Surface Finish
    • Here at Advantage, our Grade 100 Alloy Chain is our own “BLUE CAT Finish. Finishes vary by supplier.  Grade 100 Alloy Chain be Self Colored (no rust-proofing) as well.
  • Grade 100 Alloy Common Uses
    • Grade 100, pound for pound is stronger than Grade 80. Grade 100 Chain is primarily used in Overhead Lifting (OHL) applications or high strength requirement applications such as Heavy Vehicle Recovery, pulling excavation equipment from mud, etc. A fabricated rigging product, known as a Chain Sling, is fabricated, and inspected by a qualified individual, using products engineered for the agreed upon application.  There are many different Chain Sling configurations.  Each Grade 100 Chain Sling has a unique rating that coincides with the grade and configuration.  Rigging training is required when using Certified Chain Slings.  It is required that Grade 100 Hooks and Components be used on Grade 100 Certified Chain Slings in order to maintain its Safe Working Load rating.  Using components such as hooks that are Graded below Grade 100 (such as a Grade 70 or Grade 80 hook), shall make the Chain Sling out of compliance with OSHA Standards.
    • Grade 100 is approved by USDOT for use in Cargo Control on Interstate Highways

Chapter 2: STANDARD CHAIN TERMINOLOGY

  • Chain Hardware – Also known as chain fittings, these are items such as hooks, master links, coupling links, etc.
  • Working Load Limit – Also known as the Safe Working Load, WLL, SWL or Working Load is the maximum load which should ever be applied to the product under any condition. The WLL is based on a load being uniformly applied in a straight-line pull.
  • Proof Load – The load a product can withstand during the manufacturer’s quality control testing for the purpose of detecting defects and deformation in the material. The Proof Load for chain is applied at twice the value of the Working Load Limit.
  • Minimum Breaking Strength (MBS) – Do NOT use MBS for design or rating purposes. Always use the Working Load Limit instead. Minimum Breaking Strength is an average figure at which samples have been found to break under laboratory conditions, in straight-line pulls with constantly increasing loads. These conditions are rarely duplicated in actual use.  The MBS applies ONLY to new, unused chain
  • Lift Angle – A term applied to Chain Slings, the lift angle affects the WLL. When a Lift Angle is higher, the rating of the sling also increases.  When the Lift Angle decreases, the working Load Limit also decreases.
  • Sling Tag – An end user has the right to know the capacity of the sling he/she are using. A sling tag will show the critical information that the end user will need to select the proper rigging for the job.  This information on a chain sling will show Manufacturer Name, Manufacture Date, Certification Number (which normally can correspond to a paper/digital Certificate of Conformance), Chain Diameter, Number of Legs, Working Load Limits (at different lift angles if multi legged), Reach Measurement and Sling Configuration.
  • Reach – A term applied to Chain Slings, it is the measurement from bearing point to bearing point. This measurement must be accurate.  During a chain sling inspection, reach discrepancies can indicate overloading, stretch or equipment modification.
  • Design Factor – An industry term denoting a particular products’ theoretical reserve capacity. It is a Ratio which divides the MBS/WLL.
    • Grade 30 Proof Coil 4:1
    • Grade 43 High Test 3:1
    • Grade 70 Transport      4:1
    • Grade 80 Alloy 4:1
    • Grade 100 Alloy 4:1

 

  • Fatigue/Cycle Test – A test administered to gauge the durability of products. In the chain and hardware industry, this applies only to Grade 80 and Grade 100 products.  This test is administered at 1.5 times the working load and has a minimum cycle count of 20,000 to be considered a passing test
  • Shock Load – Loads which exceed the static load caused by rapidly changing movements such as jerking, impacting, or swinging of load. Working Load Limits Do Not Apply in these conditions.

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Chapter 2: CHAIN INSPECTION – A BRIEF INTRODUCTION

The following information is from ASME Code B30.9. This Code has been adopted by OSHA as the governing safety guideline for the use of Slings.  ASME B30.9 was designed to help end users identify Chain and Chain Components that have become unsafe.

 

BE SAFE, DON’T LIFT WITH DAMAGED RIGGING

ASME B30.9-1.9.5 Removal Criteria for Chain Slings

An alloy steel chain sling shall be removed from service if any of the following conditions are present:
a) Missing or illegible sling identification (see Section 9-1.7).
b) Cracks or breaks.
c) Excessive wear, nicks, or gouges. Minimum thickness on chain links shall not be below the values listed in Table 9-1.9.5-1.
d) Stretched chain links or fittings.
e) Bent, twisted, or deformed chain links or fittings.
f) Evidence of heat damage.
g) Excessive pitting or corrosion.
h) Lack of ability of chain or fittings to hinge (articulate) freely.
i) Weld splatter.
j) For hooks, removal criteria as stated in ASME B30.10.
k) For rigging hardware, removal criteria as stated in ASME B30.26.
l) Other conditions, including visible damage, that cause doubt as to continued use of the sling.

The end user’s health and safety must always be the most important concern.  No amount of monetary savings is worth an injury.  No rigging product can operate indefinitely at its rated capacity.  Chain and Chain Slings must be inspected regularly by a trained or qualified individual for visible damage, corrosion, distortion, elongation, cracks, nicks or abrasion.  These conditions may cause failure resulting in property damage, injury or death.  These conditions may cause failure or reduce the strength or ability of the product to perform safely.

ALWAYS REMOVE DAMAGED SLINGS FROM SERVICE

ADVANTAGE UNIVERSITY – THE ADVANTAGE OF KNOWING