2 1926.251 General Rigging inspected prior to shift(s) As necessary during useRemoved if defectiveRemove rigging equipment when not in useRigging equipment for material handling shall be inspected prior to use on each shift and as necessary during its use to ensure that it is safe. Defective rigging equipment shall be removed from service.Rigging equipment shall not be loaded in excess of its recommended safe working load, as prescribed in Tables H-1 through H-20 in this subpart, following (e) for the specific equipment.Rigging equipment, when not in use, shall be removed from the immediate work area so as not to present a hazard to employees.
3 1926.251 Scope Covers slings and hoisting material handling equipment Alloy steel chain,Wire rope,Metal mesh,Natural or synthetic fiber rope (conventional three strand construction), andSynthetic web (nylon, polyester, and polypropylene)."Scope." This section applies to slings used in conjunction with other material handling equipment for the movement of material by hoisting, in employments covered by this part. The types of slings covered are those made from alloy steel chain, wire rope, metal mesh, natural or synthetic fiber rope (conventional three strand construction), and synthetic web (nylon, polyester, and polypropylene).
4 1926.251(a) Rigging equipment for material handling (5) "Scope." This section applies to slings used in conjunction withother material handling equipment for the movement of material byhoisting, in employment's covered by this part. The types of slingscovered are those made from alloy steel chain, wire rope, metal mesh, natural or synthetic fiber rope (conventional three strand construction), and synthetic web (nylon, polyester, and polypropylene).(a)(6)(6) "Inspections." Each day before being used, the sling and allfastenings 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.Synthetic FiberMetal MeshAlloy SteelWire Rope
5 (b) Alloy Steel ChainPermanently affixed durable identification statingSize,Grade,Rated capacity, andSling manufacturer.All attachments capacity at least equal to chainWelded alloy steel chain slings shall have permanently affixed durable identification stating size, grade, rated capacity, and sling manufacturer.Hooks, rings, oblong links, pear-shaped links, welded or mechanical coupling links, or other attachments, when used with alloy steel chains, shall have a rated capacity at least equal to that of the chain.
6 (b) Alloy Steel ChainJob or shop hooks and links, or makeshift fasteners, formed from bolts, rods, etc., or other such attachments, shall not be used.
7 1926.251(b) Alloy Steel Chain CP inspections made & based on: (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 at least once a yearDocumented & availableIn addition to the inspection required by other paragraphs 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.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.
8 (c) Wire RopeFollow manufacturers safe working load recommendations, or Tables H - 3 through H - 14No knots in wire rope except where permitted in (c)(3) & (c)(4)(ii)Tables H-3 through H-14 shall be used to determine the safe working loads of various sizes and classifications of improved plow steel wire rope and wire rope slings with various types of terminals. For sizes, classifications, and grades not included in these tables, the safe working load recommended by the manufacturer for specific, identifiable products shall be followed, provided that a safety factor of not less than 5 is maintained.Wire rope shall not be secured by knots, except on haul back lines on scrapers.Except for eye splices in the ends of wires and for endless rope slings, each wire rope used in hoisting or lowering, or in pulling loads, shall consist of one continuous piece without knot or splice.
9 1926.251(c) Wire Rope End strands covered or blunted Protruding ends of strands in splices on slings and bridles shall be covered or blunted.
10 (c) Wire RopeWire rope shall not be used if, in any length of eight diameters, the total number of visible broken wires exceeds 10 percent of the total number of wires, or if the rope shows other signs of excessive wear, corrosion, or defect.
11 (c) Wire RopeU-bolt applied so that the "U" section is in contact with the dead end of the rope.Use Table H - 20 to determine number and spacing of clipsNever shorten slings with knots or boltsProtect slings from sharp edges(Not for bridles, slings)U-bolt wire rope clips(c)(4) The following limitations shall apply to the use of wire rope:(i) An eye splice made in any wire rope shall have not less than three full tucks. However, this requirement shall not operate to preclude the use of another form of splice or connection which can be shown to be as efficient and which is not otherwise prohibited.(ii) Except for eye splices in the ends of wires and for endless rope slings, each wire rope used in hoisting or lowering, or in pulling loads, shall consist of one continuous piece without knot or splice.(iii) Eyes in wire rope bridles, slings, or bull wires shall not be formed by wire rope clips or knots.(iv) Wire rope shall not be used if, in any length of eight diameters, the total number of visible broken wires exceeds 10 percent of the total number of wires, or if the rope shows other signs of excessive wear,corrosion, or defect.(5) When U-bolt wire rope clips are used to form eyes, Table H-20 shall be used to determine the number and spacing of clips.(i) When used for eye splices, the U-bolt shall be applied so that the "U" section is in contact with the dead end of the rope.(c)(6) Slings shall not be shortened with knots or bolts or other makeshift devices.Never saddle adead horse
12 1926.251(c) Wire Rope Never apply a shock load when lifting Never place finger between sling & load when tightening
13 1926.251(d) Natural & Synthetic Rope Tables H - 15 through H - 18 applyKnots not used instead of splicesRemove from service if:Abnormal wear.Powdered fiber between strands.Broken or cut fibers.Discoloration or rotting.
14 (e) Synthetic Webbing(e) Synthetic webbing (nylon, polyester, and polypropylene).(1)Each synthetic web sling marked or coded to show:(i) Name or trademark of manufacturer.(ii) Rated capacities for the type of hitch.(iii) Type of material.(e) Synthetic webbing (nylon, polyester, and polypropylene).(1) The employer shall have each synthetic web sling marked or coded to show:(i) Name or trademark of manufacturer.(ii) Rated capacities for the type of hitch.(iii) Type of material.(2) Rated capacity shall not be exceeded.(3) "Webbing." Synthetic webbing shall be of uniform thickness and width and selvage edges shall not be split from the webbing's width.(4) "Fittings." Fittings shall be:(i) Of a minimum breaking strength equal to that of the sling; and(ii) Free of all sharp edges that could in any way damage the webbing.
15 1926.251(e) Synthetic Webbing Don’t use around acids or phenolics Remove from service if:Acid or caustic burnsMelting or charring of any part of the sling surface;Snags, punctures, tears or cuts;Broken or worn stitches; orDistortion of fittings.Nylon web slings shall not be used where fumes, vapors, sprays, mists or liquids of acids or phenolics are present.Polyester and polypropylene web slings shall not be used where fumes, vapors, sprays, mists or liquids of caustics are present.Web slings with aluminum fittings shall not be used where fumes, vapors, sprays, mists or liquids of caustics are present.
17 1926.251 (f) Shackles and hooks. Use Table H - 19 Use manufacturers recommendationsTested to twice the intended safe working load before they are initially put into use. Maintain a record of the dates and results of such tests.
19 Rigging Safety Between the trolley hook and the load is RIGGING Ropes, Slings, ChainsOSHA-Slings inspected dailyProper storage when not in useSuitable protection of rigging when in use (items with sharp corners, etc..)
20 Rules for Rigging Safety 1. Know the weight of the load.2. Know the center of gravity of the load.3. Make load attachment above the center of gravity of the load.4. Select hitch that will hold and control.5. Know the rated capacity of slings and hardware.
21 Rules for Rigging Safety 6. Select sling best suited for load.7. Inspect all rigging before the lift.8. Protect sling from sharp surfaces.
22 Rules for Rigging Safety 9. Proper calculation of increased tension caused by sling angles (on all rigging components!).10. Allow for D/D ratio on all slings.11. Calculate reductions when using choker hitch.
23 Rules for Rigging Safety 12. Keep personnel clear from lift area.13. Lift load a few inches then check rigging.14. Know limitations of all lifting devices used.15. Lift slowly and stop slowly.
24 Hooks Hooks are used for lifting, towing, pulling and securing. Two general classifications:Sling Hooks: to which load or force is applied tothe base (bowl saddle).Grab Hooks: contain a throat or slot of uniform width for securing on the link of a chain, usuallyto form a chain loop for securing the load.
25 ! WARNING! Do not exceed the working load limit Only use alloy heat treated hooks for over-head liftingDo not tip load or use the hook in any manner for which it was not intendedDo not shock load or dynamic loadNever apply load to hook latches, latchesare only to retain slack chains and slings
26 Basics of Hook Inspections WearDeformationCracksSharp NicksCheck throat openingCheck for wear & deformationCheck for twistingCheck for wear & cracks
27 Only foundry hooks are designed for tip loading BDECHook/Load AnglesA. Balanced 100%B. 1/4 off center 86%C. 1/2 off center 80%D. 3/4 off center 70%E. Point loading 40%
29 Hoist Chains Four grades: Grade 28 General Utility ChainGrade 43 High Test ChainGrade 70 Binding ChainGrade 80 Alloy Steel Chain: The only one used for overhead lifting!Ranges in size from 7/32 to 11/4 link diameter.Check for wear, gouges, stretch, shearingInspection is LINK by LINKTwisted link extremely unsafeUse with grab hooksTags: should be on every chain: Size, Grade, Capacity
30 Hoist Chains Hoist load chains do not stretch (they wear) Sling chains chain stretch % before failureGrades are indicated on side of linkG 80
31 Outside of the link barrels are exposed to damage from foreign objects, on straight portion.These surfaces are in compression, so reduces harmful effect.Tensile stress areas are protected by chain geometry.Gouges in areas of tensile stress are of greatest concern, especiallyif they are perpendicular to the direction of stress.
32 (b)(5) Whenever wear at any point of any chain link exceeds that shown in Table H-2, the assembly shall be removed from service.
33 Corrosion can reduce link cross-section. Link by linkinspection isfacilitated bycollapsing thechainCorrosion can reduce link cross-section.Wear occurs in areas of high rubbing:1. The bearing points of interlink contact.2. Outside of straight side barrels.
35 The load on quadruple branch slings seldom have the load evenly distributedevenly among the four branches.For this reason sling charts for quadbranch slings set the load limit for quadbranch slings to the equivalent ratingfor a triple branch sling of the sametype.
36 A wire rope is a Machine with many moving parts CoreCenterStrandWire rope
37 Wire Rope Cores Fiber IWRC Strand Core is full of oil and oil oozes out to lubricate the stands and wires.If the lubrication is lacking then wires will not slide but will abrade as they go over each other during wire rope movement.Another purpose of the core is to maintain the circular shape of the wire rope.FiberIWRCStrand
38 How to describe any wire rope A typical wire rope may bedesignated 6X25 FW PRF RLL XIP IWRC. This translates to:A 6 strand (6X25) of filler wire construction (FW).The grade of wire used is Extra Improved Plow Steel (XIP).The strands are preformed (PRF) in helical pattern before being laid Right lang (RLL) around an Independent Wire Rope Core (IWRC).Each strandcontains 25wiresStrand
39 Ropes and chains shall be regularly lubricated LUBRICATIONRopes and chains shall be regularly lubricated
40 Three basic components: 1. Wires that form the strand2. Multi-wire strands that are laid helically around the core.3. The core.Most common high-carbon steel.Core is rope foundation, it provides support for strands for load and bending.Core either strand or independent wire rope core (IWRC)
41 A machine with several hundred moving parts A machine with several hundred moving parts. Requires proper maintenance.One lay = dist. for strand to make one revolution (appx 6.5 times the diameter).
42 Wire rope wear is based on: 1. Loading2. Bending (# of times)3. # of use cyclesChange in rope diameter is criteria forretirement.The area in a wire rope to check wear iswhere it travels over the block in thesection from picking a load to lifting it.Wires need lubrication to prevent corrosion. Apply by spray, brush or dip.Wire tends to wear flat on outer strands,especially where it travels over drums &sheaves.
52 Straight SlingNot good for loose or long loads, or loads that can tip.The total weight of the load is supported by a single legThe working load limit of the sling must exceed the load
53 Spreader beams can be used with a double vertical hitch to handle long loads Reduces load tippingEach leg will carry one-half the total loadSpreader beams must be manufactured for that purpose and have a rated capacity indicated
62 Calculating the load on sling legs Divide the total load by the number of sling legsThis quotient is the load on each leg if verticalMeasure the sling from the load attachment point, to the point where it connects with the hook or lifting device; this is ‘L’Measure the vertical height from the top of the load to the hook or lifting device; this is ‘H’Divide the length of the leg by the height of the sling
63 (Load Number of legs) X (L H) = Load each sling leg
64 ExampleLoad = 120,000 pounds4 load legs ÷ 120,000 equals 30,000 pounds each leg if vertical hitchSling legs are 20 feetHeight from top of load to lifting device is 15 feet20 ÷ 15 = 1.33Load on each leg is 1.33 x 30,000 = 40,000 pounds20'15'120,000 lb.
65 Center of Gravity A load is stable when: The hook is directly above the center of gravity of the loadEstimate the center of gravityLift the load just enough to clear the groundIf the hook is not over the center of gravity the hook will travel to the center of gravityCG?
66 The longer set of sling legs (B) will improve load stability Center of GravityIf necessary, set the load down and adjust the riggingIf the load tips more than 3°, the rigging should be adjustedThe longer the sling legs, the more stable the load will beBThe longer set of sling legs (B) will improve load stabilityA