Have some questions? We can help! We've compiled our most frequently asked questions below ranging from lifting slings, rigging hardware, fall protection, wire rope slings, and more. If you can't find the answer you're looking for,
contact us and we'll help you any way we can!
The Tell-Tails are overload indicators and will retract and eventually disappear if the sling is overloaded. The Fiber Optic determines if the interior core of the sling has suffered chemical, heat or crushing damage. If light does not pass from one end to the other, remove the sling from service and send to the manufacturer for repair evaluation.
Slings used with fittings shall be compatible with the fittings used. The lifting capacity shall be rated at the lower of the sling or fitting. Fitting openings shall be of the proper shape and size to assure that the sling will seat properly.
At rated capacity, nylon slings will stretch up to 15%. Round slings made with polyester will stretch 3%. Braided Polyester slings will stretch 9%. Twin-Path Extra Slings w/ K-Spec core yarn stretch less than 1% at rated capacity.
Yes. As part of our manufacturing process, each Twin-Path Extra Sling is proof tested to two times its vertical rated capacity. Every repaired Twin-Path Extra Sling is also proof tested before it is returned to the customer.
The word "sharp" is considered subjective and is no longer used in our catalog or website. Any material can be cut when exposed to enough pressure and a sharp edge. Diamonds, the hardest substance known, can be split into smaller parts by skilled cutters. CornerMax Pads must be utilized to protect the sling from all edges and corners. For an example, press your hand against the edge of a table. If you run your hand back and forth with some pressure applied, you'll realize that the edge doesn't need to be "sharp" to cut.
Abrasion protection is needed when the sling is wrapped around a load which is rough, dirty or gritty. Cut protection is needed when there is an edge or corner that the sling will come in contact with.
The differences are usually not a factor in most sling applications. At rated capacity, a treated nylon sling stretches approximately 7-10%, whereas a treated polyester sling will stretch approximately 3.5-5%. The extra stretch in nylon helps to avoid shock loading. Polyester’s smaller stretch factor makes load control easier by reducing bounce. In a chemical environment, nylon should not be used in acidic environments, including those where bleaching agents are present while polyester should not be used near various aldehydes.
A sling connects the crane hook to the load and is an import rigging tool. Slings can be made of steel wire rope, chains or synthetic man made fibers like polyester, nylon, K-spec or Kevlar. A synthetic sling is a sling made up of synthetic yarn like nylon, polyester or K-spec.
The K-spec fiber is the "best" fiber in terms of high strength and very low stretch equivalent to steel. However it is also an expensive fiber. But for slings of capacity over 30 Metric Tones safe working load, there is no alternative to K-spec fiber. However, for slings of capacity from 1 MT to 30 MT, polyester and nylon are normally used. Polyester is a preferred fiber because it stretches much less than nylon and has much better resistance to chemicals and sunlight.
Aside from personal preference, no. As the sling mfg., Bairstow warrants that all of our products are free from defects in materials and workmanship and adhere to all known engineering and manufacturing standards. Routine testing is performed on all of the materials we use to assure that you are getting only the highest quality products.
The Flemish splice method tends to result in varying degrees of strand looping in the sling eye during fabrication and the amount of high stranding varies based on the base wire rope diameter. This condition is not a cause for removal from service as sling strength and durability are not affected. However, high strands in the sling BODY do affect sling strength and indicate that the sling has been damaged and should be removed from service immediately.
All grade 100 chain slings are approximately 25% stronger than grade 80 chain slings of the same diameter. The chain is harder, resulting in greater resistance to wear and, therefore, longer life. As of 2008, Bairstow offers grade 100 chain slings as our standard offering.
Welded chain slings are connected via permanent, welded connections making them “tamper proof”, this offers assurance you have an assembly which has not been compromised with an incompatible component. However, mechanical assemblies allow for quick and easy fabrication, as well as, repairs in the event of potential sling damage.
Chain and steel mesh slings can be repaired, along with, minor outer jacket damage on Twin Path and Single Path (with Tell Tail/Fiber Optics and/or the Check Fast Inspections system) high performance round slings. However, web slings, standard polyester round slings and wire rope slings cannot be repaired, but, their undamaged hardware can be reused in remanufactured assemblies.
Any of our high performance or polyester round slings can be made in excess of 100 ft. in length. For other types of slings the maximum length varies, please contact firstname.lastname@example.org or 800-241-8990 for further details.
Round Pin Shackles can be used in tie down, towing, suspension or lifting applications where the load is strictly applied in-line. Screw Pin Shackles can be used in any application where a round pin shackle is used. In addition, screw pin shackles can be used for applications involving side-loading circumstances. Reduced working load limits are required for side-loading applications. While in service, do not allow the screw pin to be rotated by a live line, such as a choker application. Bolt-Type Shackles can be used in any applications where round pin or screw pin shackles are used. In addition, they are recommended for permanent or long term installations and where the load may slide on the shackle pin causing the pin to rotate.
This would depend on the style of hook being used, For a regular Single Point Hook it is recommended that a maximum of 2 slings are used on the hook, if the user needs to use more than 2 slings to lift the load then a collector ring such as a Link or Shackle should be used between the Hook and the Slings.
If the hook is a Duplex or Quad Hook (2 or 4 pointed) then the Hook points must be equally loaded to balance the forces on the Hook.
The ASME B30.26 standard says: Each turnbuckle, eyebolt, and eye nut shall be marked to show
name or trademark of manufacturer
size or rated load
grade for alloy eyebolts
So the WLL limit does not have to be marked on the Eyebolt if the size is, as the user you must make yourself aware of the WLL by referring to the manufacturers specification for the style, size and material of the Eyebolts you are using.
A new OSHA standard for Cranes in Construction goes in to effect November 8, 2010. It requires operators of most cranes above 2,000 pounds capacity when used in construction to be either certified by an accredited crane operator testing organization or qualified through an audited employer program. It requires a "Qualified" rigger and signal person. See standard for exact details. A copy of the regulatory text is available at http://www.osha.gov/doc/cranesreg.pdf.
The new OSHA standard says that a "qualified rigger" is someone who meets the definition of a qualified person. OSHA states that a "Qualified Person" is - a person who by possession of a recognized degree or certificate of professional standing, or who, by extensive knowledge, training and experience, has successfully demonstrated the ability to solve or resolve problems relating to the subject matter and work.
A qualified rigger is required during the assembly/disassembly of cranes, and when employees are engaged in hooking, unhooking or guiding the load, or in initial connection of a load to a component or structure and are within the fall zone.
The area (including but not limited to the area directly beneath the load) in which it is reasonably foreseeable that partially or completely suspended materials could fall in the event of an accident.
Yes. Crosby does offer a two-day Rigging Trainer Development course at no charge to full line Crosby Distributors and end users of our products. Day one is designed for those product users who need fundamentals of rigging only. Day two is designed for trainers or individuals that need more advanced information. Students who wish to attend day two must have attended the day one 24 hours prior.
List of what successful day two attendees receive from Crosby:
PowerPoint files provided by Crosby that can be utilized by end user trainers in their classroom training sessions for educating their employees on fundamentals of rigging while using Crosby rigging hardware in conjunction with slings.
All day one attendees receive a certificate for attending the "Fundamentals of Rigging" class and successful day two attendees receive a certificate stating that they are authorized to use Crosby training materials for 48 months from date of issue.
Successful day two attendees also receive a certificate stating they have earned 1.9 "CEUs"
Authorization to purchase Crosby classroom training materials at discounted rates for their in-house rigging training needs.
CD ROMs for computer based rigging training sessions. Those individuals who successfully complete a Crosby CD ROM computer based training program can request a Certificate of Achievement from Crosby for documentation of education achieved.
CD ROM with PowerPoint files for 30 ? 45 minute refresher rigging training sessions.
Note: Interested parties working in manufacturing or construction environments should request the ASME/OSHA Rigging Trainer Development Schedule from Crosby. If working in Land Based Oil or Gas environments please request the Land Based Rigging Trainer Development Schedule. If working in offshore environments, please request the API Rigging Trainer Development Schedule. Seminar schedules for the two-day Rigging Trainer Development courses can be downloaded from the Crosby website: www.thecrosbygroup.com. Click onto "Training"and select "Seminar Schedule."
No! Crosby does not certify riggers. Certification normally requires passing a written and hands on practical exam administered by a third party. Crosby however does provide educational seminars that greatly help individuals in their endeavors to become a competent or qualified rigger. The time spent in our seminars and certificate of training received goes a long way in proving rigger qualifications when using Crosby rigging products in conjunction with slings. The education achieved can also prove useful in preparing for the written and practical exams to be a certified rigger. See information later in this memo on how to become a certified rigger. To request an "On Site" 4 or 8 hour Crosby seminar, please sign onto the Crosby website www.thecrosbygroup.com. Click onto "Training" and select "Request for On Site Seminar". Proper paperwork must be submitted and reviewed by Crosby before training can be confirmed.
Normally one must pass a written and a practical "hands on" exam. The organizations below administer or offer rigger certification.
NCCCO ? National Commission for the Certification of Crane Operators ? www.nccco.org
NCCER ? National Center for Construction Education and Research ? www.nccer.org
Contact ACRP (Association of Crane and Rigging Professionals) ? www.acrp.net for other possible sources of testing.
Note: Some cities, states or employers may have special requirements.
Crosby offers 4 and 8 hour rigging seminars at no charge for end users of our products. (Certain criteria must be met.)
Crosby offers two-day Rigging Trainer Development courses at no charge in selective cities nationwide.
Crosby provides all seminar attendees complete set of training materials at no charge.
Crosby offers computer based rigging training programs via CD ROM.
Beginning November 2010, all two-day seminar attendees will receive at no charge "prep" materials for the NCCCO Level I rigger exams.
Crosby issues Certificate of Achievement to all seminar attendees. This certificate provides proof of attendance as a means to document one's education on the subject matter provided.
Crosby has trained over 250,000 individuals since 1991.
Most Crosby end user seminars are conducted by "certified" riggers.
Special Note: Classroom training as provided by Crosby is only one element in becoming a qualified, competent, or certified rigger. Crosby strongly encourages that seminar attendees also obtain "hands on" training and appropriate on the job experience as well.
See Crosby "Seminar Schedules" for list of two and three day Rigging Trainer Development courses offered in selective cities.
See Crosby "Request On Site Training" to request a possible on site Crosby four hour or eight hour seminar.
By Phone: Primary contact is Julie Wilson at 918-834-4611 ext. 235 or secondary contact is Toni Vestal at ext. 357.
Via E-mail: Seminar schedules for the two-day Rigging Trainer Development courses can be downloaded from the Crosby website at: www.thecrosbygroup.com