wire rope clips osha factory
Wire rope is often used in slings because of its strength, durability, abrasion resistance and ability to conform to the shape of the loads on which it is used. In addition, wire rope slings are able to lift hot materials.
Wire rope used in slings can be made of ropes with either Independent Wire Rope Core (IWRC) or a fiber-core. It should be noted that a sling manufactured with a fiber-core is usually more flexible but is less resistant to environmental damage. Conversely, a core that is made of a wire rope strand tends to have greater strength and is more resistant to heat damage.
Wire rope may be manufactured using different rope lays. The lay of a wire rope describes the direction the wires and strands are twisted during the construction of the rope. Most wire rope is right lay, regular lay. This type of rope has the widest range of applications. Wire rope slings may be made of other wire rope lays at the recommendation of the sling manufacturer or a qualified person.
Wire rope slings are made from various grades of wire rope, but the most common grades in use are Extra Improved Plow Steel (EIPS) and Extra Extra Improved Plow Steel (EEIPS). These wire ropes are manufactured and tested in accordance with ASTM guidelines. If other grades of wire rope are used, use them in accordance with the manufacturer"s recommendations and guidance.
When selecting a wire rope sling to give the best service, consider four characteristics: strength, ability to bend without distortion, ability to withstand abrasive wear, and ability to withstand abuse.
Rated loads (capacities) for single-leg vertical, choker, basket hitches, and two-, three-, and four-leg bridle slings for specific grades of wire rope slings are as shown in Tables 7 through 15.
Ensure that slings made of rope with 6×19 and 6x37 classifications and cable slings have a minimum clear length of rope 10 times the component rope diameter between splices, sleeves, or end fittings unless approved by a qualified person,
Ensure that braided slings have a minimum clear length of rope 40 times the component rope diameter between the loops or end fittings unless approved by a qualified person,
Do not use wire rope clips to fabricate wire rope slings, except where the application precludes the use of prefabricated slings and where the sling is designed for the specific application by a qualified person,
Although OSHA"s sling standard does not require you to make and maintain records of inspections, the ASME standard contains provisions on inspection records.[3]
Ensure that wire rope slings have suitable characteristics for the type of load, hitch, and environment in which they will be used and that they are not used with loads in excess of the rated load capacities described in the appropriate tables. When D/d ratios (Fig. 4) are smaller than those listed in the tables, consult the sling manufacturer. Follow other safe operating practices, including:
When D/d ratios (see Fig. 6) smaller than those cited in the tables are necessary, ensure that the rated load of the sling is decreased. Consult the sling manufacturer for specific data or refer to the WRTB (Wire Rope Technical Board) Wire Rope Sling Users Manual, and
Before initial use, ensure that all new swaged-socket, poured-socket, turnback-eye, mechanical joint grommets, and endless wire rope slings are proof tested by the sling manufacturer or a qualified person.
Permanently remove from service fiber-core wire rope slings of any grade if they are exposed to temperatures in excess of 180 degrees F (82 degrees C).
Follow the recommendations of the sling manufacturer when you use metallic-core wire rope slings of any grade at temperatures above 400 degrees F (204 degrees C) or below minus 40 degrees F (minus 40 degrees C).
This responds to your June 1, 1999, letter to the Occupational Safety and Health Administration (OSHA), requesting information on wire rope and Crosby clips used around the perimeter of buildings as a guardrail. You also requested clarification on when employees must tie-off when a guardrail system is removed to facilitate hoisting operations. We apologize for the long delay in providing this response.
Question 1: How many Crosby clips are required to be used when setting up a wire rope guardrail? Is it permissible to splice two wire ropes by overlapping or must the connections be turned back into eyelets and properly secured?
Answer: For construction work covered by 29 CFR 1926 Subpart M, §1926.502(b) sets forth the criteria that must be met when using wire rope as a guardrail. The standard requires guardrails to meet several specific criteria. For example, 1926.502(b)(3) states that the guardrail shall be capable of withstanding, without failure, a force of at least 200 pounds applied within 2 inches of the top edge, in any outward or downward direction, at any point along the top edge. Section 1926.502(b)(4) states that when the 200 pound test load noted in §1926.502(b)(3) is applied in a downward direction, the top edge of the guardrail shall not deflect to a height less than 39 inches above the walking/working level. Section 1926.502(b)(9) states that the top rail and mid-rails shall be at least ¼-inch nominal diameter or thickness to prevent cuts and lacerations. These and other criteria must be met when using wire rope as a guardrail around the perimeter of a building.
The OSHA standard does not specify a minimum number of clips when using wire rope as a guardrail. However, as a practical matter, it is unlikely you could meet the specific requirements under §1926.502(b) unless you follow the manufacturer"s recommendations for the number of clips to be used on wire ropes of different diameters (for example, the Crosby Group Inc. general catalog, 2000 edition has tables showing their recommendations for their clips). Also, note that OSHA"s standard for rigging equipment used for material handling, 29 CFR §1926.251, has a table for the number of clips required for wire rope ½-inch and greater. Although that standard does not apply to wire rope used for guardrails, when you design a rope system to meet the §1926.502 requirements, following those tables will normally ensure that you have enough clips.
If you need additional information, please contact us by fax at: U.S. Department of Labor, OSHA, Directorate of Construction, Office of Construction Standards and Guidance, fax # 202-693-1689. You can also contact us by mail at the above office, Room N3468, 200 Constitution Avenue, N.W., Washington, D.C. 20210, although there will be a delay in our receiving correspondence by mail.
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).
Employers must not use improved plow-steel wire rope and wire-rope slings with loads in excess of the rated capacities (i.e., working load limits) indicated on the sling by permanently affixed and legible identification markings prescribed by the manufacturer.
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.
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.
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.
Cable laid and 6 × 19 and 6 × 37 slings shall have a minimum clear length of wire rope 10 times the component rope diameter between splices, sleeves or end fittings.
Safe operating temperatures. Fiber core wire rope slings of all grades shall be permanently removed from service if they are exposed to temperatures in excess of 200 °F (93.33 °C). When nonfiber core wire rope slings of any grade are used at temperatures above 400 °F (204.44 °C) or below minus 60 °F (15.55 °C), recommendations of the sling manufacturer regarding use at that temperature shall be followed.
Wire rope slings shall have permanently affixed, legible identification markings stating size, rated capacity for the type(s) of hitch(es) used and the angle upon which it is based, and the number of legs if more than one.
Employers must not use natural- and synthetic-fiber rope slings with loads in excess of the rated capacities (i.e., working load limits) indicated on the sling by permanently affixed and legible identification markings prescribed by the manufacturer.
In manila rope, eye splices shall contain at least three full tucks, and short splices shall contain at least six full tucks (three on each side of the centerline of the splice).
In layed synthetic fiber rope, eye splices shall contain at least four full tucks, and short splices shall contain at least eight full tucks (four on each side of the centerline of the splice).
Strand end tails shall not be trimmed short (flush with the surface of the rope) immediately adjacent to the full tucks. This precaution applies to both eye and short splices and all types of fiber rope. For fiber ropes under 1-inch diameter, the tails shall project at least six rope diameters beyond the last full tuck. For fiber ropes 1-inch diameter and larger, the tails shall project at least 6 inches beyond the last full tuck. In applications where the projecting tails may be objectionable, the tails shall be tapered and spliced into the body of the rope using at least two additional tucks (which will require a tail length of approximately six rope diameters beyond the last full tuck).
Safe operating temperatures. Natural and synthetic fiber rope slings, except for wet frozen slings, may be used in a temperature range from minus 20 °F (-28.88 °C) to plus 180 °F (82.2 °C) without decreasing the working load limit. For operations outside this temperature range and for wet frozen slings, the sling manufacturer"s recommendations shall be followed.
Splicing. Spliced fiber rope slings shall not be used unless they have been spliced in accordance with the following minimum requirements and in accordance with any additional recommendations of the manufacturer:
In manila rope, eye splices shall consist of at least three full tucks, and short splices shall consist of at least six full tucks, three on each side of the splice center line.
In synthetic fiber rope, eye splices shall consist of at least four full tucks, and short splices shall consist of at least eight full tucks, four on each side of the center line.
Strand end tails shall not be trimmed flush with the surface of the rope immediately adjacent to the full tucks. This applies to all types of fiber rope and both eye and short splices. For fiber rope under 1 inch (2.54 cm) in diameter, the tail shall project at least six rope diameters beyond the last full tuck. For fiber rope 1 inch (2.54 cm) in diameter and larger, the tail shall project at least 6 inches (15.24 cm) beyond the last full tuck. Where a projecting tail interferes with the use of the sling, the tail shall be tapered and spliced into the body of the rope using at least two additional tucks (which will require a tail length of approximately six rope diameters beyond the last full tuck).
Removal from service. Natural and synthetic fiber rope slings shall be immediately removed from service if any of the following conditions are present:
Employers must use natural- and synthetic-fiber rope slings that have permanently affixed and legible identification markings that state the rated capacity for the type(s) of hitch(es) used and the angle upon which it is based, type of fiber material, and the number of legs if more than one.
Re: Wire rope clips on suspension scaffolds; safety latches on large crane hooks; hanging scaffolds - order of assembly; jobsite fabricated lifting accessories - criteria; and horizontal lifelines: use of wire rope clips, anchorages, number of persons allowed to be connected, requirements relating to sag, and use of synthetic rope.
This is in response to your facsimile dated November 14, 2003, to the Occupational Safety and Health Administration (OSHA). We have paraphrased your questions as follows:
Question 1(a) - (c): When using horizontal lifelines as part of personal fall arrest systems, what type of wire rope clips does OSHA require, and how many clips must be used? Additionally, what are the horizontal spacing criteria for the uprights?
Subpart M does not specify what type of wire rope clip or how many clips/clamps must be used when installing a horizontal lifeline. However, under §1926.502(d)(8), these decisions must be made under the supervision of a qualified person when the system is designed. The determination of the horizontal spacing criteria for uprights is also left to the qualified person"s supervisory approval.1
In an August 28, 2000 letter to Mr. Troxell2, we addressed the related issue of using wire rope clips on a wire rope guardrail. In that letter, we cautioned that, as a practical matter, it is unlikely that the criteria requirements for guardrails under §1926.502(b) could be met unless the manufacturer"s recommendations for the number of clips to be used on wire ropes of different diameters were followed (for example, the Crosby Group, Inc., general catalog 2000 edition, has tables showing their recommendations for their clips). We also pointed out that OSHA"s standard for rigging equipment used for material handling, 29 CFR 1926.251, has a table showing the number of clips required for wire rope ½-inch and greater. We noted that although that standard does not apply to wire rope used for guardrails, when designing a rope system to meet the §1926.502 guardrail requirements, following the tables at §1926.251 will normally ensure that there will be enough clips.
The forces exerted on a horizontal lifeline are substantially greater than those on a typical guardrail. Therefore, the system designer needs to ensure that the number, type, and location of clips will withstand the anticipated forces and meet the performance requirements in §1926.502 for horizontal lifelines.
Question 2: For a horizontal lifeline used as part of a personal fall arrest system during steel erection work, how tight should the lifeline be, and may synthetic rope be used for the horizontal lifeline?
Therefore, a qualified person is required to determine how tight the lifeline should be based on site-specific factors. No other requirements are imposed by OSHA regarding the tightness of the lifeline, so long as it comports with a safety factor of at least two.
With regard to the use of synthetic ropes, §1926.502(d)(14) specifies that, when using non-wire rope, synthetic rope (rather than nature fiber rope) must be used:
Question 4: Are there OSHA standards that specify criteria for constructing jobsite fabricated rigging equipment such as an equalizing beam, lifting beam, spreader beam, equalizing plates, tee lugs, lifting lugs, and welded scaffold brackets?
The only OSHA construction standards that contains specific criteria related to the construction of special custom design lifting accessories is 29 CFR 1926.251(a)(4), which states:
Question 5: Under §1926.451(d)(12)(v) and (vi), when wire rope clips are used on suspension scaffolds, "(v) U-bolt clips shall not be used at the point of suspension for any scaffold hoist," and "(vi) when U-bolt clips are used, the U-bolt shall be placed over the dead end of the rope, and the saddle shall be placed over the live end of the rope." Does §1926.451(d)(12)(v) contradict paragraph (d)(12)(vi)?
No. By its terms, §1926.451(d)(12)(v) prohibits the use of U-bolt clips at the point of suspension for any scaffold. The scaffold standard does not prohibit using U-bolt clips elsewhere. However, when using them elsewhere, under §1926.451(d)(12)(vi), the U-bolt must be placed over the dead end of the rope, and the saddle placed over the live end of the rope.
Question 6: Under §1926.251(c)(4)(iii), are eyes in wire rope bridles and slings or bull wires formed by wire rope clips permitted when used to lift scrap boxes or pendants?
This provision specifically prohibits eyes in wire rope bridles and slings or bull wires being formed by wire rope clips. There is no exception for lifting scrap boxes or pendants.
There are no OSHA standards setting criteria for horizontal high-lines. However, an employer"s use of a horizontal high-line must be in accordance with its obligations under Section 5(a)(1) of the Occupational Safety and Health Act (the "General Duty Clause"), which states:
In our view, the industry recognizes that the following engineering factors, among others, must be considered when designing horizontal high-lines: the span and sag of the wire rope line, the weight of the load being lifted, the initial tension of the rope line, and the size of the columns.
OSHA requirements for a safety latch on hooks do not depend of the size of the hook but rather the activity for which the hook is being used. Safety latches on hooks are required in two instances:
Knotting wire rope compromises the integrity of the strength of the wire rope and is therefore prohibited. Based on the picture provided, which showed a knot in wire rope secured by a U-bolt clip, this practice would be in violation of §1926.251(c)(3).
Question 10: Do OSHA standards require the attachment of an orange and white flag to the highest point of a crane that is being used in the vicinity of an airport?
There are no OSHA standards that require the highest point of a crane to be marked to enhance visibility to air traffic. However, the use of a crane in the vicinity of an airport may be subject to requirements set by other regulatory agencies, such as the Federal Aviation Administration.
Question 11: Do OSHA standards specify a particular anchorage point for connecting the lanyards of workers on crane suspended personnel platforms? Do the standards limit the number of such workers that can be attached to an anchorage point?
If you need additional information, please contact us by fax (202-693-1689) at: U.S. Department of Labor, OSHA, Office of Construction Standards and Guidance. You can also contact us by mail at U.S. Department of Labor, OSHA, Office of Construction Standards and Guidance, Room N3468, 200 Constitution Avenue, N.W., Washington, D.C. 20210, although there will be a delay in our receiving correspondence by mail.
On Sunday, January 21, 1990, at approximately 5:10 a.m., Employee #1, a licensed tankerman, was employed by Riverside Marine Services, which was contracted to off load a barge containing isobutane at the BP Oil Refinery (dockside) in Belle Chasse, LA. The barge had been off loaded, and Employee #1 had disconnected the flange on the Chiksan south marine arm, which was the vapor line, from the barge and was storing the arm on the dock. Three Crosby fist grip clips were attached to the 0.625-inch wire rope retaining line. The clips came off the wire rope, allowing the marine arm to swing violently back and forth. The lower end of the arm, the flange end, struck Employee #1 in his right chest and killed him. Upon investigation, it was found that a stud on one of the clips did not have a nut on it and the paint on the clip did not indicate that a nut was ever on the bolt. The remaining clip bolts had very little paint scrapings, indicating that the nuts were never fully torqued either at the factory or upon installation at the refinery. Once any weight was applied to the retaining cable, the fist grip clips could not hold the weight and the wire rope slipped, allowing the marine arm to swing.
Original equipment wire rope and replacement wire rope must be selected and installed in accordance with the requirements of this section. Selection of replacement wire rope must be in accordance with the recommendations of the wire rope manufacturer, the equipment manufacturer, or a qualified person.
Wire rope design criteria: Wire rope (other than rotation resistant rope) must comply with either Option (1) or Option (2) of this section, as follows:
Option (1). Wire rope must comply with section 5-1.7.1 of ASME B30.5-2004 (incorporated by reference, see § 1926.6) except that section"s paragraph (c) must not apply.
Option (2). Wire rope must be designed to have, in relation to the equipment"s rated capacity, a sufficient minimum breaking force and design factor so that compliance with the applicable inspection provisions in § 1926.1413 will be an effective means of preventing sudden rope failure.
Type I rotation resistant wire rope ("Type I"). Type I rotation resistant rope is stranded rope constructed to have little or no tendency to rotate or, if guided, transmits little or no torque. It has at least 15 outer strands and comprises an assembly of at least three layers of strands laid helically over a center in two operations. The direction of lay of the outer strands is opposite to that of the underlying layer.
Type II rotation resistant wire rope ("Type II"). Type II rotation resistant rope is stranded rope constructed to have significant resistance to rotation. It has at least 10 outer strands and comprises an assembly of two or more layers of strands laid helically over a center in two or three operations. The direction of lay of the outer strands is opposite to that of the underlying layer.
Type III rotation resistant wire rope ("Type III"). Type III rotation resistant rope is stranded rope constructed to have limited resistance to rotation. It has no more than nine outer strands, and comprises an assembly of two layers of strands laid helically over a center in two operations. The direction of lay of the outer strands is opposite to that of the underlying layer.
Type I must have an operating design factor of no less than 5, except where the wire rope manufacturer and the equipment manufacturer approves the design factor, in writing.
A qualified person must inspect the rope in accordance with § 1926.1413(a). The rope must be used only if the qualified person determines that there are no deficiencies constituting a hazard. In making this determination, more than one broken wire in any one rope lay must be considered a hazard.
Each lift made under § 1926.1414(e)(3) must be recorded in the monthly and annual inspection documents. Such prior uses must be considered by the qualified person in determining whether to use the rope again.
Rotation resistant ropes may be used as boom hoist reeving when load hoists are used as boom hoists for attachments such as luffing attachments or boom and mast attachment systems. Under these conditions, all of the following requirements must be met:
The requirements in ASME B30.5-2004 sections 5-1.3.2(a), (a)(2) through (a)(4), (b) and (d) (incorporated by reference, see § 1926.6) except that the minimum pitch diameter for sheaves used in multiple rope reeving is 18 times the nominal diameter of the rope used (instead of the value of 16 specified in section 5-1.3.2(d)).
The operating design factor for these ropes must be the total minimum breaking force of all parts of rope in the system divided by the load imposed on the rope system when supporting the static weights of the structure and the load within the equipment"s rated capacity.
Wire rope clips used in conjunction with wedge sockets must be attached to the unloaded dead end of the rope only, except that the use of devices specifically designed for dead-ending rope in a wedge socket is permitted.
Prior to cutting a wire rope, seizings must be placed on each side of the point to be cut. The length and number of seizings must be in accordance with the wire rope manufacturer"s instructions.
Silver State Wire Rope and Rigging, Inc. with general offices, manufacturing facility and warehousing in Las Vegas and Elko, Nevada is the only company of it’s kind in the state. With several divisions, we specialize in a broad spectrum of rigging related services.
(a) 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 allow steel chain, wire rope, metal mesh, natural or synthetic fiber rope (conventional three strand construction), and synthetic web (nylon, polyester, and polypropylene).
“Cable laid endless sling-mechanical joint” is a wire rope sling made endless by joining the ends of a single length of cable laid rope with one or more metallic fittings.
“Cable laid grommet-hand tucked” is an endless wire rope sling made from one length of rope wrapped six times around a core formed by hand tucking the ends of the rope inside the six wraps.
“Cable laid rope sling-mechanical joint” is a wire rope sling made from a cable laid rope with eyes fabricated by pressing or swaging one or more metal sleeves over the rope junction.
“Master link” or “gathering ring” is a forged or welded steel link used to support all members (legs) or an alloy steel chain sling or wire rope sling. (See Fig. N-184-3.)
“Strand laid endless sling-mechanical joint” is a wire rope sling made endless from one length of rope with the ends joined by one or more metallic fittings.
“Strand laid grommet-hand tucked” is an endless wire rope sling made from one length of strand wrapped six times around a core formed by hand tucking the ends of the strand inside the six wraps.
“Strand laid rope” is a wire rope made with strands (usually six or eight) wrapped around a fiber core, wire strand core, or independent wire rope core (IWRC).
Employers must use only wire-rope slings that have permanently affixed and legible identification markings as prescribed by the manufacturer and that indicate the recommended safe working load for the type(s) of hitch(es) used, the angle upon which it is based, and the number of legs if more than one.”
Contact IBT to schedule a Sling Safety Seminar. The Sling Safety Seminar will be tailored to your facility’s needs. Let IBT and Lift-All train your employees to be compliant with the new OSHA regulation for wire rope slings.
Cable guardrails are commonly seen on construction projects. Although they can provide adequate protection at perimeter edges, they often have issues with the way they are installed. Risk Managers should keep the below in mind to share with their workers and safety committees. If properly constructed and maintained, cable guardrails can provide compliant fall protection in numerous situations.
Typically, cable guardrails are erected by ironworkers at the final interior and exterior perimeters of floors upon completion of installing the deck. However, cast-in-place concrete structures may transition from wood guard rails to cable guardrails installed by carpenters. As part of the floor turnover process for a steel or concrete building, controlling contractors often times direct the contractor who installed the system to leave the perimeter cables in place until the fall exposure is removed by setting windows or curtain wall. At this point, the controlling contractor inspects and accepts control of the fall protection if it meets the following criteria set forth by OSHA 1926 Subpart M regulations:
It is highly recommended anyone who installs or maintains safety cables be trained and authorized. These systems are initially compliant, but when tampered with or removed by others throughout the course of construction and not replaced properly, they can be a safety concern.
Excessive Deflection or Sagging – incorporate turnbuckles to allow for easy tightening of the cable. Another option is to keep a cable puller and wire rope grip attachment handy in order to tighten cable guardrails easily.
System Not Properly Terminated – common issues include wire rope clips installed backwards, not enough wire rope clips, and the cables are improperly spliced. The U-Bolt of the clip should be applied to the dead end of the wire rope and the saddle on the live end. This is what the phrase,“Never saddle a dead horse!” refers to. There should be at least two clips installed for wire rope that is ¼” – 3/8” in diameter. Lastly, the preferred method to terminating the wire rope or splicing two wire ropes together is to turnback the ends through each eye as seen in the diagrams.
An alternative method to splicing two wire ropes together is to lay the wire rope ends parallel and correctly apply the proper amount of wire rope clips as depicted in the diagrams.
Safety cable guardrails can provide OSHA compliant fall protection for employees on a construction project. However, they must be continuously inspected and maintained to ensure compliance with OSHA 1926 Subpart M standards.
Patent stoppers of the clamp type shall be appropriate for the size of the rope used. Clamps shall be in good condition and free of any substance that would prevent their being drawn tight.
The end of the winch fall shall be secured to the drum by clamps, U-bolts, shackles, or other equally strong methods. Fiber rope fastenings shall not be used.
When an employee works in the bight formed by the heel block, a preventer at least three-quarters of an inch (1.91 cm) in diameter wire rope shall be securely rigged, or equally effective means shall be taken, to hold the block and fall if the heel block attachments fail. Where physical limitations prohibit the fitting of a wire rope preventer of the required size, two turns of a one-half inch (1.27 cm) diameter wire rope shall be sufficient.