4.2 ASME B30.26 Hardware and B30.20 Below-the-Hook

Key Takeaways

  • ASME B30.26 covers rigging hardware such as shackles, eye bolts, turnbuckles, links, rings, swivels, and compression hardware used in lifting assemblies.
  • ASME B30.20 covers below-the-hook lifting devices—structural and mechanical attachments between the hoist/hook and the load (beams, clamps, magnets, and related categories).
  • Hardware and below-the-hook devices must be marked with manufacturer identity and rated capacity (or equivalent required marking) and used only within those ratings and the manufacturer’s configuration rules.
  • Level I riggers connect provided, identified hardware correctly—pin orientation, shoulder eye bolts, load path through rated parts—and do not improvise unmarked or mismatched fittings.
Last updated: July 2026

Completing the Load Path Below the Hook

Slings and crane hooks rarely work alone. Between the hook and the load you will almost always find rigging hardware—shackles, eye bolts, master links, turnbuckles, swivels—and sometimes a below-the-hook lifting device such as a spreader beam, lifting beam, plate clamp, or magnet. The ASME volumes that organize this equipment for industry practice are:

  • ASME B30.26 — Rigging Hardware
  • ASME B30.20 — Below-the-Hook Lifting Devices

On the NCCCO Rigger Level I exam, Technical Knowledge questions use these standards to test whether you know what category of gear you are using, whether it is identified and rated, and whether the load path through that gear is correct. You are not redesigning beams; you are applying provided, marked equipment within its ratings.

ASME B30.26 — Rigging Hardware

B30.26 addresses forged and fabricated hardware commonly used to connect slings, loads, and hoist hooks. Exact chapter organization in the published standard groups product families; for exam purposes, memorize the main product types and the use principles that appear repeatedly in training and written items.

Hardware categories a Level I rigger must recognize

Hardware (B30.26 family)Typical function in the load pathHigh-value use rule
Shackles (anchor/chain, screw pin, bolt-type)Connect sling eyes to hooks, master links, or lift pointsPin fully engaged; load along shackle body; do not side-load the pin as a beam unless designed
Eye bolts / eye nutsProvide a threaded lift point in a structure or machineShoulder type for angular loading when allowed; thread engagement and alignment critical
TurnbucklesAdjust length/tension in a bracing or leveling assemblyUse only models rated for lifting if in the load path; lock against unintended loosening
Links and rings (including master / intermediate links)Collect multiple sling legs or connect componentsRated for the total system load and geometry
SwivelsAllow rotation to reduce twist in the assemblyMust be load-rated; not a substitute for uncontrolled spin of an unstable load
Compression hardware (wire rope clips, sockets, wedges—as covered)Terminate or secure wire rope in certain assembliesInstall per manufacturer torque/orientation; never invent clip counts
Other fittings (hooks with hardware roles, couplers, etc., as included)Specialized connectionsOnly as marked and instructed

Shackles — everyday B30.26 practice

Shackles are the most common B30.26 item on Level I jobs and exams.

Screw-pin shackles are convenient for frequent connect/disconnect. The pin must be screwed fully in; if the pin can work loose under movement, secure it per manufacturer guidance (and many sites require mousing or prefer bolt-type for critical long-duration connections).

Bolt-type shackles use a nut and cotter (or equivalent retention). They are preferred where the connection will remain in place, vibrate, or see movement that could back out a screw pin.

Loading rules that drive correct answers:

  1. Apply load in the plane of the shackle bow so the body takes tension as designed.
  2. Do not use a shackle pin as a makeshift load pin in bending unless the product is specifically designed for that geometry.
  3. Avoid eccentric loading that pries the bow open.
  4. Match shackle size and WLL to the sling and lift point—never force an undersized shackle because “it almost fits.”
  5. When multiple sling eyes share a shackle, confirm the capacity and geometry still work; crowding can create uneven loading and latch/hook problems at the crane hook—often a master link is cleaner.
Shackle issueWhy it fails technical review
Pin only half threadedPin can disengage; capacity and retention lost
Side load on pin like a hinge bolt without design basisBending and unplanned stress
Shackle smaller than sling capacityWeak link in series
Using a non-rated farm or unknown shackleNo verified WLL or material pedigree
Bow deformed / openedGeometry no longer matches design

Eye bolts — angular loading awareness

Eye bolts are a frequent trap. A plain non-shoulder eye bolt is generally intended for in-line loading along the axis of the shank. Shoulder eye bolts, when properly seated against the load surface and used within manufacturer angular charts, can accept angular loading in the plane of the eye. Key points:

  • Full thread engagement into a sound tapped hole or with a proper nut/washer system as designed.
  • Shoulder must bear flush on the load surface for angular applications that rely on the shoulder.
  • Load in the plane of the eye; loading at 90° out of that plane can bend the eye.
  • Do not use damaged, stretched, or unmarked eye bolts as lifting points.
  • Manufacturer angular reduction charts—not field guesses—control capacity at an angle.

Turnbuckles, links, rings, and swivels

Turnbuckles in a lifting load path must be designed and marked for lifting, not random hardware-store frame tighteners. Ends (eye, jaw, hook styles) must match the connection method, and threads must have adequate engagement with locking provisions against rotation under load or vibration.

Master links and rings often head multi-leg sling assemblies. Their rating must account for the resultant from leg angles—not merely “sum of vertical ratings” without geometry. Level I typically uses assemblies already built and tagged; your job is to verify identification and use them in the intended configuration.

Swivels allow rotation to manage twist. They must be rated for the load. A swivel does not automatically stabilize a load with a high or offset center of gravity; tag lines and proper hitching still control attitude.

Compression hardware awareness

Where wire rope terminations use clips, sockets, or wedge sockets, B30.26-aligned practice and manufacturer instructions control number of clips, saddle orientation (“never saddle a dead horse”), torque, and inspection. Level I candidates should know that terminations are engineered assembly details, not improvisations. An incorrectly clipped eye can fail well below the rope’s catalog strength.

ASME B30.20 — Below-the-Hook Lifting Devices

ASME B30.20 covers below-the-hook lifting devices: structural and mechanical devices fastened to a hoist or crane hook to handle a load. These are not ordinary single slings; they are purpose-built devices that often have their own design categories, markings, and operating instructions.

Category awareness (Level I technical map)

You do not need to design these devices for the written exam, but you must recognize major categories and the idea that each has rated capacity, marking, and use limits.

B30.20-oriented categoryExamplesRigger awareness
Structural lifting devicesSpreader beams, lifting beams, frames, end capsShare load or control sling angles; never exceed beam rating or hanger spacing limits
Mechanical lifting devicesPlate clamps, sheet lifters, tongs, grabs (as applicable)Gripping depends on surface condition, thickness range, and lock engagement
Close-proximity operated magnets (category awareness)Lifting magnets used near operatorsPower/control reliability, residual magnetism, and exclusion zones matter
Remote-operated magnets (category awareness)Magnets operated from a distanceSame capacity discipline plus control-loss risk management
Vacuum devices (when treated as below-the-hook systems in practice)Vacuum pad liftersSeal integrity, surface cleanliness, and loss-of-vacuum protection
Other specialty devicesCustom engineered liftersFollow the specific device documentation

Spreader beams primarily put sling legs in nearly vertical tension by placing compression in the beam, improving angles. Lifting beams often introduce bending in the beam as hangers pick the load at points along the span. Either way, the device rating, attachment method, and load placement on the beam are mandatory—not optional.

Plate clamps depend on correct plate thickness range, surface condition (oil, scale, coatings), and locking mechanisms. Using a clamp outside its thickness range or on plates that violate manufacturer surface rules is a technical misuse even if the clamp “bites” initially.

Magnets require category-appropriate controls: verify rated capacity for the material thickness and surface, confirm power or permanent-magnet status, keep personnel out of the fall zone, and understand that loss of magnetism or incomplete contact can drop the load without a mechanical “backup sling” unless the procedure provides one.

Marking and Rated Capacity Concepts

Across B30.26 hardware and B30.20 devices, a consistent technical theme appears:

  1. Manufacturer identification must be present.
  2. Rated load / working load limit must be marked (or provided by the required marking system for that product).
  3. Use only in configurations the manufacturer rates.
  4. Missing or illegible marking → do not use as rated lifting equipment until properly addressed.
  5. Components in series are limited by the weakest rated link (and by geometry that can increase tension above the vertical load).
ConceptPractical meaning
Rated capacity / WLLMaximum load for the intended configuration under manufacturer/standard rules
Design factorBuilt into the rating by the manufacturer/standard; users do not casually “take extra” by guessing
Series load pathHook → shackle → sling → eye bolt: each must be adequate for the forces present
Geometry multiplierAngles and side loads can make force in a component higher than load weight
Matching grades/sizesAlloy chain, fittings, and master links are systems—not random mix-and-match

Level I application: connect what is provided, correctly

NCCCO Level I emphasizes simple, repetitive lifts when weight, CG, and configuration are known. That still requires hardware literacy:

  • Select shackles and fittings that match the provided sling assembly and lift points.
  • Orient pins and shoulders as designed.
  • Confirm markings before the load leaves the ground.
  • Refuse unmarked, improvised, or obviously mismatched hardware.
  • Recognize when a below-the-hook device is required (awkward shape, need for spread, plate handling) rather than forcing a single choker that side-loads points.

Common exam myths

MythCorrect thinking
“Hardware is unregulated; only slings have ASME standards”B30.26 specifically covers rigging hardware
“Any beam can be a spreader if steel is thick”Below-the-hook devices need design, marking, and rated capacity under B30.20 practice
“Eye bolts always allow 45° pulls”Angular capacity depends on type (shoulder vs non-shoulder) and manufacturer chart
“Magnet rating is unlimited for steel”Magnets have capacity limits tied to material, thickness, surface, and device type
“If it fits the hole, the shackle is big enough”Capacity and geometry—not hole fit alone—control selection

If you can classify an item as B30.26 hardware or B30.20 below-the-hook, verify its marking and WLL, and assemble the load path without side-loading pins or improvising unmarked gear, you have the technical core of this section for both the exam and the field.

Test Your Knowledge

Which ASME standard primarily covers shackles, eye bolts, turnbuckles, links, rings, and similar rigging fittings?

A
B
C
D
Test Your Knowledge

A structural spreader beam is used under the crane hook to keep sling legs nearly vertical. Which ASME standard family is the primary technical home for such below-the-hook lifting devices?

A
B
C
D
Test Your Knowledge

A shoulder eye bolt will be loaded at an angle in the plane of the eye. What technical condition is required for proper use within manufacturer angular ratings?

A
B
C
D
Test Your Knowledge

A bolt-type shackle is selected for a long-duration outdoor connection that will see vibration. Why is this often preferred over a loose screw-pin shackle in that service?

A
B
C
D