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Lift-It Manufacturing, a leading supplier of slings and rigging, has once again achieved a production milestone, supplying its largest cargo net to date.

Lift-It’s latest and largest cargo net. Previously, the company’s largest heavy-duty cargo nets measured 25 feet by 25 feet, and were used to lift a 50,000-pound artifact in the Hawaiian Islands. More recently, a refinery in Trinidad and Tobago presented Lift-It’s experts with an even more substantial challenge: a 34-foot by 34-foot Barrier Net which, when completed, included 29 pounds of thread! The company also provided tie-down assemblies for the Orion Lunar Mission. The tie-down assemblies featured high-performance webbing and supported the inflatable bags that absorbed the impact of the landing. To receive Lift-It’s new 500-page Resource Guide and view the details of upcoming training opportunities and other custom-designed products, visit www.lift-it.com.

Mike Gelskey, Sr., Past President of the Web Sling and Tie Down Association (WSTDA) presented the details of a fatality resulting from the use of a damaged sling at the Fall 2012 meeting of the WSTDA held in Minneapolis, MN. The presentation explored the circumstances of the unfortunate and premature death of Rodney Armstrong Guy, a 32 year old lineman.  Rodney Guy was killed at 2:15 PM on March 20, 1992 during a clipping operation of a 500kV transmission line in Rio Vista, CA. The sling had been used for 33 months and twice previously the very day Rodney was killed. Several factors lead to his death. The sling was severely overloaded as it was dynamically loaded to 14,000 lbs. as the line was clipped into the insulator.  The sling work load limit was 8860 Lbs.  In addition to the sling overload, there was no advance calculation done to determine the work load requirement. The sling was also severely UV degraded.  A nylon sling continually exposed to sources of ultraviolet light for periods ranging from 12-30 months may lose 40 to 60% of original strength. The sling was severely damaged and either the damage was ignored or the sling was not inspected prior to use. While making presentations in Mandan, North Dakota Mike Gelskey met Mr. Vince Smith, who was working with Rodney the day he was killed.  Mr. Smith provided Gelskey with a picture of Rodney and eerily the sling that snapped can be seen in its extremely distressed state in the background. The sling separated at the exact midpoint , in a straight line propelling the block into Rodney’s chest, killing him instantly as a result of blunt trauma to chest and abdomen. The damaged $40 sling could have been replaced after a 40 mile drive to West Sacramento. 40 miles, 40 dollars and proper training is all it would  have taken for Rodney  to enjoy Grandchildren at this point in his life. The members of the WSTDA expressed their appreciation for Gelskey’s  presentation. Mr. Rodney Armstrong Guy

Mike Gelskey, Sr., Chief Executive Officer, Lift-It Manufacturing presented on September 13th and 14th at the 2012 Canadian Crane and Rigging Conference, sponsored by Maximum Capacity Media in Edmonton, Canada. Mr. Gelskey presented a Management and Safety Overview of Regulatory, Industry and Association Developments in the sling and rigging industry.

Many web sling manufacturers have referred to Red Core Yarns as Red Core “WARNING” yarns. The red core “WARNING” yarns should simply be referred to as Red Core Yarns.

“Warning” should be omitted as there is a false sense of security and an unreasonable emphasis placed on the red core yarns by uneducated sling users and inspectors.   Red Core Yarns are not a viable inspection device. By the time the red core yarns become visible; the sling should be rejected and removed from service.

Lift-It Manufacturing utilizes webbing with red core yarns to fabricate our web slings.  Some manufacturers do not use sling webbing with red core yarns and use commercial equivalents of “Mil-Spec” or tie down webbing that does not employ red core yarns. All slings should be fabricated from sling webbing, not tie down webbing. ASME B30.9-Chapter 5- Web Slings stipulates the use of sling webbing for slings and references the Web Sling and Tie Down Association, Recommended Standard Specification, Webbing for Synthetic Web Slings, WSTDA-WB-1.

It is important that sling fabricators and safety professionals put the proper emphasis on the red yarns. In our Resource Guide, warning sheets and warning tags, the red core yarns are listed, but are placed at the end of the removal from service criteria.

Too much emphasis is put on the singular importance of the red core yarns in the inspection process. How many seasoned sling users can repeat the limerick that unfortunately is a part of our safety culture, “If I see red, I’m going to be dead”?  So the reverse logic, “If I don’t see red, I get to go home and watch “Dancing with the Stars” makes sense?

When taken in isolation red core yarns will not serve the user or the rigging industry well. We have always instructed responsible sling users and inspectors that if the red core yarns are visible do not use the sling. However, slings can become extremely dirty, making red core yarns difficult to see.  Serious damage can also be present without red core yarns being visible. Our advice has always been, if there is damage WITHOUT the red core yarns visible, DO NOT USE THE SLING.

Safety and training professionals MUST send out the correct message by providing the proper perspective on red core yarns. Students must not leave a training session with the idea that all they need to look for and be aware of are red core yarns. Get your mind right and visit our web site http://www.lift-it.com and obtain additional information on the right perspective to have when it comes to sling webbing vs. tie down webbing and the overrated value placed on red core yarns.

Mike Gelskey, Sr.

CEO-Lift-It Mfg.

 
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In the 1990’s an article was published stating that synthetic slings lose strength, strictly as a function of time. The article relayed the results of destruction testing performed on USED slings taken from power plants, line trucks, paper mills and other locations. A majority of the slings broke below the necessary value to justify a 5/1 design factor.

The less than scientific conclusion of the testing was that synthetic slings lose strength as a function of time and I was mentioned, possibly to add credence to the incorrect conclusion by making the point that if shelf life were not valid, “Gelskey would not put the date of manufacture on all slings made by his company”.

The logic was incorrect on any levels. The so called experiment lacked many basic elements necessary to prove the hypothesis under what is accepted as the scientific method. The independent variable, time was not isolated.

The sample slings pulled to destruction in this study had been subjected to use, weather and environmental factors. They could have been exposed to overloading, chemical and ultraviolet degradation or perhaps were not manufactured properly.

We date and individually serialize our slings so that users and inspectors will have an exact idea of how long our slings have been in service. Our rationale was that despite appearances slings may be removed from service and destroyed as many are very inexpensive when compared to the cost of the items they handle. Simply stated, sling retirement may be an excellent form of cheap insurance.

When slings are stored for extended periods in conditions that do not exactly duplicate optimum storage conditions, sling strength may be affected. An example would be when slings in Eastern Washington (desert conditions) are stored outside in metal containers. Those slings can take on spring steel qualities and recoil to assume their wrapped condition. After many years slings stored inside under conditions that DO NOT EXACTLY DUPLICATE optimal storage conditions, can begin to exhibit a gummy or sticky finish.

We have on a couple of occasions pulled slings to destruction that were kept in optimum storage conditions: dry, dark, cool and free of mechanical and environmental damage. In all instances the slings broke above the 5/1 design factor. Both slings were approximately eleven years old.

The salient difference in the destruction tests done by Lift-It and the testing done in the early 90’s is that the Lift-It test slings were never used for lifting or subjected to any form of degradation. Under these conditions, the independent variable, time was indeed isolated.

In the early nineties when the non-scientific study results were published I was assailed by webbing and yarn producers.  I was informed on more than one occasion that synthetic fibers DO NOT lose strength strictly as a function of time. On one particular occasion, a fiber producer was extremely profane in making this exact point to me based upon extensive testing in oxidation chambers. Those results contradicted the incorrect conclusion made in the article.

Time, as independent variable, DOES NOT affect sling strength. Other variables such as storage and exposure to chemical, environmental and mechanical forms of damage do affect sling strength. Always remember, sling design factors apply only to newly manufactured and unused slings.

Mike Gelskey, Sr.

CEO-Lift-It Mfg.

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The effect of active chemical exposure on synthetics is an important consideration for responsible sling users, safety and training professionals. Many aspects must be considered. Time, temperature and concentration are primary considerations, but certainly not the only factors.

For many years we have relied upon yarn engineers at various webbing mills where synthetic materials are made into webbing products for their opinions on application or suitability.  The problem with those opinions is that they generally DO NOT take into account the cumulative effect of multiple chemicals and/or unique environmental factors. We also surveyed more than one mill to determine if all responses would be similar.

Beyond chemical compatibility, other factors must also be considered.  An example would be if certain chemical agents are exposed to moisture or UV light resulting in degradation that would not be realized in dry or dark applications.

For these reasons we have always encouraged sling users to work with their suppliers and ultimately their manufacturers to determine the effects of exposure in real world settings with adequate controls to validate results through the scientific method.

There is new vigor in the concern for the effects of marking pen ink commonly used in the fabrication of synthetic products and sling safety.

Years ago we presented our prime supplier at the time, Murdock Webbing with the MSDS for Sharpie Markers and their analysis revealed that nothing in the ingredients would be harmful to either nylon or polyester materials.

Most recently at a Canadian Crane and Safety Conference, the issue was raised again when information from a marker manufacturer stated that Xylene could be harmful to synthetic materials.

We contacted Avery Dennison, manufacturer of Marks-A-Lot markers and Newell- Rubbermaid, manufacturer of Sharpie markers and requested their assessment of the chemical effects of the marker ink ingredients on synthetic webbing.  Given today’s global economy we attempted obtaining this information from phone contacts in foreign countries and given the litigious society we did not receive expedient responses. To date, the only response we have received is from Avery Dennison. Their representative stated Xylene was not an ingredient in their product and cited the legal jargon referencing the doctrines of implied and express warranties of merchantability and fitness.

We also contacted three webbing manufacturers to obtain their opinion by providing MSDS information for both markers.  We also asked that the effects of UV exposure combined with all chemical ingredients be taken into account to determine if the interaction would be deleterious. A summary follows:

 

Webbing Mill No. 1
“Based on the information supplied to us by Kordsa, Nylon has excellent resistance to Xylene.  Polyester on the other hand is not resistant to Xylene.   As far as the effects by adding UV exposure, I could find no information.  We would only need to worry about the added effects of UV on Nylon”.

(OK, Mr. Webbing Mill Manufacturer No. 1. You should purchase a copy of the WSTDA-UV study as UV degradation also affects polyester fibers!)

Webbing Mill No. 2
“I couldn’t find any data supporting the combination with UV rays but what I did find says that Xylene is not harmful to polyester but it is harmful to nylon. Nylon will lose 10-20% of its strength after 10 hours and at a temperature of 282 F in combination with Xylene. Hope this helps. Sounds like polyester is the best bet for the application and it should be better for UV as well”.

Follow up Question and reply for Web Mill No. 2:
Q: What was the concentration of the Xylene in your recommendation based upon?
A: “The concentration was 100% and this data was for yarn only. With a web being thicker, who knows?”

Webbing Mill No. 3
The quick answer is that as an organic solvent, Xylene is on the list of TOCs, so it is ‘harmful’ under certain circumstances.  But it is a commonly used solvent, cleaning agent, etc.  It is subject to photo-oxidation, with the production of by-products that are also chemically active. Polyester is not considered to be stable to Xylene even at 15C. So, if you had continuous contact with Xylene and polyester it would be an issue and would begin to break down the yarn in a short period of time. Polyamides (nylon) tend to have pretty good resistance to most aromatic hydrocarbon solvents at room temperatures so no issue there.

Sharpie markers causing problems due to Xylene content in the ink is the point of the question. I would not expect the use of such a marking pen on an organic polymeric material under normal temperatures/light exposure to cause degradation of the polymeric material due to the Xylene content in the ink.  The Xylene will evaporate very quickly upon making a mark with the pen so there will be no degradation.

Most of this data is from the technical resource I use at Clemson’s textile school down the road from us. (Dr. Deborah Lickfield)

Webbing Mill 1 and 2 respond with conflicting information: Webbing Mill 1 claims Nylon would be better resistant to the effects of Xylene, while Webbing Mill 2 opines that polyester would be a better fiber. If you are confused at this point, you should be!  There seems to be some agreement between Webbing Mill 1 and 3 relative to the superiority of nylon to polyester with respect to Xylene exposure.

 

Lift-It Manufacturing has used Marks-a-Lot and Sharpie markers for nearly 33 years and has had not experienced a single incidence of sling failure as a result of exposure to the ink ingredients in the aforementioned markers.  We have pulled thousands of slings to destruction in both new and aged states (10-15 year old slings) and obtained satisfactory results.

In my involvement with Web Sling and Tie Down Association (WSTDA), I queried 50 manufacturers at the 30th Annual Meeting in Newport Rhode Island and no one had a single case to report relative to failure or incidence resulting from exposure of webbing to marker pen ink.

I would also stipulate that my comments are made STRICTLY from the context of synthetic slings and DO NOT apply to marker pens used on fall prevention equipment, harnesses, etc.

My comments also DO NOT apply to ALL marker pens, just the two previously mentioned brands.  Other markers may contain different ingredients and entirely different results.

From an assessment standpoint it would be impossible to determine the specific marker manufacturer and the specific ingredients if field personnel were marking products.  If the marking is done to record inspection and testing there are far better ways to accomplish the objective: RFID, Inspection Loops, Non-Metallic Inspection Tags, etc.

Responsible users need to contact their manufacturers for their assessment to determine the effects of the specific ink used on synthetic products.

It was interesting to note that on the surface Xylene is a TOC (Toxic Organic Chemical), but that the evaporation process would need to be considered.  It was also interesting to note that Mill No. 2 when queried replied that the analysis was based upon a 100% concentration and that Xylene penetration would be a function of material thickness and resultant degradation.

Based upon the information received from Webbing Mill No. 3, the testing done by Lift-it on unused, new and old slings, we can say that the ink used to mark slings manufactured by Lift-It does not degrade our synthetic slings.

Sincerely,

Mike Gelskey, Sr.
Chief Executive Officer

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