Strapping Training Ersoy Tuncay – 2012

GENERAL COMPARISON

RANGE OF USEs OF STRAPPING Chains, wire rope, Woven polyester, etc. LASHING Weight of Application STEEL Strap COMPOSITE STRAPPING PET Strap PPStrap / Stretch film Market Volume

Strapping types in General Steel strapping: Magnus-strap 1000 - 1070 Newton/mm2 Heavy packs Apex-strap 780 - 900 Newton/mm2 Simple / medium typ applications / cost reductions Plastic strapping: PET strap PET high strength 16 – 32 mm (6.000 – 18.800 Newton) Normal PET 9 – 16 mm (2.000 – 5.000 Newton) PP strapping Machine strapping 5 – 16 mm (500 – 4.500 Newton) Manual strapping 11 - 15 mm (2.000 – 3.000 Newton) Polyester Corded Strapping Manuel Application As strong as Steel Strap and excellent retain tension performance ( 2000 kgf Break Strength)

STRAPPING NORMS AND STANDARTS

STRAP PROPERTIES Strength Tensile Strength Break Strength Joint Efficiency Working Range Retained Tension Elongation and Recovery Impact Resistance

Tensile Strength Tensile strength is characteristic of a type of material and the way it has been processed PP 320 N/mm2 PET 400 N/mm2 PET 450 N/mm2 Apex STEEL 850 N/mm2 Magnus STEEL 1050 N/mm2 Composite Strapping n/a ( No homogenous Crossection)

Break strength is characteristic of a specific strap. It is the product of cross-sectional area and tensile strength PET 19mm x 1.27mm x 450N/mm2 = ~ 11,000N Magnus Steel Strap 19mmx0.63mm = 19mm x 0.63mm x 1.050N/mm2 = ~ 12,500N

Joint Strengts The joint strength determines the loop strength! Examples for PET Strapping: Pneumatic hand tools 45 to 60% (Stick to min for variations in air pressure and flow or PET sheet material.) Battery Charged Tool 60 to 75% (Depending on strap type sheet single extruded) Machines 80 to 90 % single extruded

Joint Strength of Composite Strapping JOINT EFFICIENCY of POLYESTER CORDED COMPOSITE STRAPS : 80 – 90 %

Joint Strength of Steel Strapping at Different Joint Types

Retained Tension Retained tension is the strap tension that remains over time Applied tension is the tension that is initially applied to a strap Tension decay is the tension that is lost over time Retained tension : Steel    90 to 95% PET      65 to 75% PP        25 to 35% Composite Strap 80 to 90% The size of the strap does not affect the RT.

WORKING RANGE

Working Range Working range of PET and steel strap are about 50% of their break strengths. Working range of PP is about 35% of its break strength. Working range elongation is the main reason why PET is tougher than steel. Steel     0.2 -0.3 % PET      2 - 4% PP- Special 6% Composite Strapping 4 – 6%

Impact resistance Impact resistance is measured by work (energy necessary) to break/deform the strap. Calculation: Working range (%) x Joint strength (N) x Working range elongation (%) Comparison between Steel Strap 32 x 0,8 applied with a double notch seal, and a PET 19 x1,27mm PET Strap with battery tool : Apex 31,75 x 0,8 mm BS is 20.000Nx 70% JS = 14.000 N 50% x 14.000 x 0,3 = 2.100 Nmm PET 19,05 x 1,27 BS is 10.000 N x 75% JS = 7.500 N 50% x 7.500 x 4 = 15.000 Nmm So the PET Strap and also COMPOSITE STRAPs in this case is half the strength but 7 ( Seven) times tougher!!!!

Steel Strap Composite / PET Strap POUNDS / NEWTONS Steel Strap Break Strength (BS) = 11,120 Newtons: PET Strap BS = 5,560 Newtons 3,000 / 13345 2,500 / 11,120 2,000 / 8,896 1.500 / 6,672 1,000 / 4,448 500 / 2,224 POUNDS / NEWTONS LOAD - ELONGATION CURVE 3,000 2,500 1,000 500 1,500 2,000 2 1 6 5 4 3 7 8 ELONGATION Pounds Steel Strap Composite / PET Strap Work to break Steel 400 units WORK = 1/2x0.3x2000 300 units Work to break Composite / PET Strap WORK = 1/2x1000x4 2000 units

Choosing Your Strap

Factors affecting strap choice Function or purpose of the strap Package characteristics Shipping or handling considerations Strapping may perform the following functions: package reinforcement, carton closure, securement, unitization, baling, bundling, bracing, paletization, compression retention and pilferage reduction. Package characteristics that influence strap selection are: weight, stability, rigidity, integrity and sharpness of the edges (sharp edges may demand heavier strapping or corner protection). Shipping considerations that affect the choice of strapping include: how far the package is shipped; how it’s handled by both the shipper and receiver; and where and how it’s stored.

EQUIPMENT BY PACKAGE TYPES Shape: Rectangular Normal hand-tools / Machines Round Push type tools / (Machines) Weight: How much mass has to be held together? Weight Straps Package stability: Is the product stabile by itself, is the stacking stabile? Strapping to hold pack on pallet, or to hold pack together? What happens when a strap breaks? Costs Safety Product edges: Does strap damage product? Corner-protection Does product damage strap? Need to distribute more tension?

Transport (Intern/Extern) You may ask yourself the following questions: How is the pack lifted / handled? Forklift, magnetic overhead crane, roller-conveyor, etc. How long is the pack in storage? Shrinking, corrosion. Conditions of storage? Moisture, dust, sunlight, heat, ice, etc. Way of storage? Stacked, in racks Way of transport? Truck, train (shunting), ship, airfreight. Distance of transport? Domestic or Export, the more transport actions, the higher the risk .

At the end customer How does the end customer handle the package? Forklift truck, roller conveyor, magnetic crane, etc. How / when does he take the packaging apart? Any hazards, complications? Is there intermediate storage? Many more handlings, very long storage times. Does the pack get resold? Needs to be broken down to smaller units. Try to think further …..

Types of Steel Strapping Apex is a cold-rolled, low carbon steel strapping. It is used for light and medium duty loads that needhigh strength and high retained tension but are not subject to impacts or shock. Magnus steel strapping is made from higher-carbon, cold-rolled, heat treated steel. It is used on heavy/very heavy loads that require high strength and are subject to impacts andshock during transit and handling. USLM steel strapping is made from higher-carbon, cold-rolled, heat treated steel. It is used on very heavy/extreme loads.

Chemical Analysis of Steel Strap Types

Why waffled strap Advantages: Disadvantages at heavy waffling : A thicker strap with a lower Gram / Meter (Cheaper) Stiffer, good feeding through chutes Disadvantages at heavy waffling : Longer weldtime, or weaker weld. Less meterage per Kg. Tension-wheel grips in “air” A smaller smooth strap can replace a wider waffled strap.

TRUCK TRANSPORTATION

RAILWAY TRANSPORTATION

SEA TRANSPORTATION

NUMBER of STRAPS REQUIRED CALCULATION Minimum Number of Straps =(Load Weight x G Force x 1,5 )/System Strength 1,5 : Safety Factor Safety Factor can be varied according the transportation mode and also type of the product. System Strength of Composite Strapping = 1,6 x Nominal Break Strength

Çember Miktarı Hesaplama Örneği : Palet Weight : 3000 kg Strap Used : CS32ESTR Composite Strap Break Strength of the Strap : 1600 kg System Strength of the Strap : 2560 kg Safety factor : 1,5 Minimum # of Straps should be on the Pallet = 3000 x 1,5 / 2560 = 1,76 Two ( 2 ) Straps

Steel Strapping vs PET / Composite Strapping Steel Strapping has : Advantages Disadvantages High Corner Strentgth Low Elasticity High Breaking Strength Low Elongation Recovery Tensionable with hand, pneumatic or fully automatic machines Low Shock Absorbency ( Impact ) High Static System Strength if closed properly Low3 Dynamic System Strength Can be tensioned manually or sealed with battery tensioner Dangerous to users , Damage to products Also fully automatic possible Expensive than PET / Composite strapping

Thank You Ersoy Tuncay / 2012