 |
SLING
CARE
Nylon and Polyester Slings
Feature:
Load Protection... Will not mar, deface or scratch the most highly polished metal
surface and are equally gentle with non-metallic loads.
Strength... Tensile strength is outstanding-will handle loads as great as 300,000
lbs. or more.
Convenience... Lightweight and extremely flexible; they are easily and quickly
handled and adjusted to load.
Safety... Adjusts to load contour and holds it with a tight, non-slip grip. Load
bearing inner fibers are completely covered and protected from abrasion by a tough, strong
outer woven cover. Non-sparking.
Long Life... Unaffected by mildew, rot or bacteria, and have excellent abrasion
resistance. All LIFTEX slings in Nylon and Polyester are treated to seal out moisture and
dirt, and to reduce the effects of abrasion.
Economy... Low initial cost plus long service life.
Shock Absorbent... Synthetic webbing slings have elongation characteristics that
minimize the effects of shock loading. All loads are cushioned with minimum jarring.
Indicator Core... All slings in this catalog (except the Reversed Eye Type) have RED
indicator core yarns to assist in determining slingwear or damage. If the core yarns are
visible the sling should be replaced. (WARNING: In some applications slings become very
dirty making it difficult to see the red yarns. All slings should be carefully inspected
before using).
|
| Sling Performance
Characteristics and Factors Effecting Performance Nylon and Polyester Performance Characteristics
Nylon and Polyester are the most popular and best general-purpose synthetic webbing
slings.
Nylon
- Unaffected by grease or oil.
- Good Chemical resistance. *
- Not to be used in acids or bleaching agents.
- Not suitable for use at temperatures exceeding 194 degrees Fahrenheit
- Elongation approx. 10% at rated capacity.
Polyester
- Unaffected by grease or oil.
- Good Chemical resistance. *
- Not to be used in concentrated sulfuric acid.
- Not suitable for use at temperatures exceeding 194 degrees Fahrenheit
- Elongation approx. 10% at rated capacity.
Factors Effecting
Performance of Web Slings
Sharp Edges
All Synthetic webbing slings are subject to cutting when lifting items with sharp edges
in contact with the sling should be padded with material of sufficient strength to prevent
damage to the sling. Wear pads give extra protection to the sling where the most wear
occurs. Please refer to page 16 for description of types of wear pads supplied by Liftex
Corp.
Ultra-Violet Light
Exposure
Environments in which synthetic webbing slings are continuously exposed to ultra-violet
light can affect the strength of synthetic webbing slings in varying degrees from slight
to total degradation.
- Suggested procedures to minimize the effects of ultra-violet light - sunlight or arc
welding flash.
A. Store slings in a cool, dry and dark place when not being used for prolonged periods
of time.
B. Inspect slings weekly or more
frequently depending on sling use.
- Visual indications of ultra-violet degradation are:
A. Bleaching out of sling color.
B. Increased stiffness of sling material.
C. Surface abrasion in areas not normally in contact with the load.
Slings used in environments where they are subject to continuous exposure to ultra-
violet light should be proof tested to two times rated capacity annually or more
frequently depending on severity of exposure.
* Chemically Active Environments
Chemically active environments can effect the strength of webbing slings in varying
degrees, ranging from none to total degradation. Before ordering slings that are to be
used in chemically active environments, give us a call. We shall be pleased to recommend
the right sling for the right usage.
Acids
- Nylon is subject to degradation in acids ranging from none to total degradation.
- Polyester is resistant to many acids, but is subject to degradation ranging from none to
moderate in some alkalis.
Alkalis
- Nylon is resistant to many alkalis, but is subject to degradation ranging from none to
moderate in some alkalis.
- Polyester is subject to degradation in alkalis, ranging from none to total degradation.
Each application must be evaluated, taking into consideration the following:
a. Type of acid, alkali or other chemical
b. Exposure conditions
c. Concentration
d. Temperature
Sling Stresses at Different Angles
When selecting a sling to carry a given load, it is important to consider the angle at
which the sling will be used, as in the basket hitch in the diagram. As the angle A
increases, the load to which the sling is subjected increases substantially.
Refer to Sling Load factor chart below for determining actual sling stress, or call for
the phone number of your nearest Liftex Corp., representatives for assistance.
|
 |
ACTUAL SLING STRESS |
= LOAD X FACTOR |
Angle |
|
Angle |
|
Degrees |
Factor |
Degree |
Factor |
0º |
1.000 |
40º |
1.305 |
5º |
1.003 |
45º |
1.414 |
10º |
1.015 |
50º |
1.555 |
15º |
1.035 |
55º |
1.743 |
20º |
1.064 |
60º |
2.000 |
25º |
1.103 |
65º |
2.366 |
30º |
1.154 |
70º |
2.924 |
35º |
1.220 |
75º |
3.863 |
|
Roundup Roundslings
The Liftex Corp. Roundup Roundsling represents a major advancement in
material handling. Roundslings offer the user the ultimate in lifting security and rigging
ease. The Roundup Roundsling is constructed from a continuous loop of 100% polyester
fiber, with the actual number of winds determining the capacity of the sling. Each Roundup
Roundsling is covered with a double polyester woven jacket to protect the load-bearing
windings from damage. Because the load-bearing windings never come in contact with the
load, they are protected from cuts, abrasions and ultraviolet degradation provided the
jacket remains intact. Each sling has a tough, resilient tag for quick and easy
identification.
Roundup the Liftex Advantages
Lightweight
- Reduce cost with less total rigging weight
- Easy handling and storage
- Reduce risk of back and hand injuries
Safety
- Cover abrasion will not reduce capacity
- Provides a strong grip on loads
- Provides a tighter choke with an easier release
- Low stretch = approximately 3% at rated capacity
- Red Core Warning Fibers alert user to damage
Sling Angle and Rated Capacity
When selecting a sling to carry a given load, it is important to consider the angle at
which the sling is to be used. As an example, one sling in a basket hitch or two slings
attached to one crane hook are different applications involving different sling angles.
The degree of the angle will determine how much capacity will be reduced. To determine if
a particular sling will have the capacity required, take the angle between the sling leg
and the horizontal, then multiply the sling's rating by the factor provided in the
accompanying table.
The capacity of a sling will be reduced as the angle from horizontal is reduced. In the
example below, you will see how the 1,000-pound capacity of a sling used in a vertical
basket hitch is reduced:
Recommended Operating
Practices
The Roundup Roundsling is a specialized tool and it should be treated like any other
specialized tool. Proper use and care of your sling can ensure a most effective life for
you, your load and your sling.
1. Know the weight of the load.
2. Use a sling with characteristics meant for the type of load, hitch and environment
with which you are working.
3. Never load a sling in excess of its rated capacity.
4. Never tie or knot a sling, or use a sling with a knot in it.
5. Protect the sling from being cut by sharp corners, edges and abrasive surfaces by
using wear pads or sleeves.
6. Make sure the sling is securely attached to the load.
7. Do not stand near or under a suspended load and keep it clear of other obstructions.
8. Do no drag a sling across the floor, over abrasive surfaces, or from under a load.
9. Don't shock (jerk) load when lifting.
10. Take damaged slings out of service immediately.
|
