Advantages and disadvantages of stretch wrap.

TM 38-400/NAVSUP PUB 572/AFMAN 23-210 MCO 4450.14/DLAM 4145.12

(b) Absence of the need for a heat

(2) When stretch-wrapping tires, the stretch

film must overlap both of the end tires at least 6 inches

source allows a less costly operation.

to assure maximum bonding.

(c) The stretch process can be used in

(3) A caution must be observed when

more environments (e.g., cold rooms).

tensioning film in the wrapping process. Overtensioning

(d) Stretch-wrapping equipment is more

of the stretch film (i.e., stretching the film to near the

portable and easier to reposition.

breaking point) causes the stretch film to lose its

(e) The stretch-wrapped unit is not as

elasticity and resistance to rupture or splitting when

waterproof as a shrink-film unit; however, a top cover

subjected to shock. Optimum performance of the

can be placed on a load and down the sides before the

stretch film occurs when the film is tensioned to a point

stretch-wrapping process begins.

where a 1-inch neckdown is obtained at the top and

g. Items not suitable for stretch-wrap application.

bottom of the film as it is dispensed from the roll. This

Few products need to be eliminated from consideration

results in a reduction of film width of approximately 10

for stretch-wrapping. However, a charge of static

percent.

electricity is developed during the stretch-wrap

f. Advantages and disadvantages of stretch wrap.

operation, especially during the stretch-wrapping of tires

(1) Most

the

advantages

and

under low relative humidity conditions. The intensity of

disadvantages stated in paragraphs 3-90f and g for

the static charge varies between the generic films with

shrink film also apply to stretch wrap when compared to

PVC films developing the highest intensities. Although

other utilizing techniques. There are some additional

this static charge is not harmful to tires, it does create a

considerations, however, when comparing stretch wrap

hazard to static-sensitive electronic components or

with shrink film.

highly flammable materials when either stretch-wrapped

(a) Since the stretch-wrap process does

or stored in the vicinity of the stretch-wrap operation.

not require heat, the equipment installation is less

complicated (e.g., no ventilation needs).

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