Parts & Consumables ยท Film Buying Guide

A complete technical guide to silage stretch film selection covering the width decision, pre-stretch settings, UV ratings, colour choice, layer count recommendations, and the quality differences that determine whether a film protects your silage investment or quietly undermines it.

New South Wales, AustraliaยทEverPower Baling Machinery Australia Pty Ltdยท+61 2 9708 3322

Silage stretch film is the component that stands between a well-made bale and an expensive pile of spoiled feed. It is also one of the most poorly understood purchasing decisions in the Australian silage system. Many operators treat film as a commodity where price is the primary criterion, when in reality the specification differences between film grades translate directly into silage quality outcomes that dwarf the cost difference between products. This guide works through every film specification that matters, explains the functional consequence of each, and provides the decision framework that enables farmers and contractors to buy the right film for their specific programme.

The Width Decision: 500mm vs 750mm

The width of silage stretch film determines how many turntable passes are required to cover the bale surface with each layer, and therefore how many total turntable rotations complete the programmed layer count. This has direct implications for wrapping speed, film consumption per bale, and the quality of coverage at the bale shoulder transitions.

500mm Film: The Standard Width

500mm film is the correct choice for smaller-diameter bales: 1.0m and 1.25m formats. At standard pre-stretch and 50% overlap, 500mm film covers approximately 250mm of bale surface per pass; wrapping a 1.25m bale at 4 layers requires approximately 12 to 14 turntable rotations depending on turntable speed and bale geometry. 500mm film is also the more commonly stocked width in Australian agricultural suppliers, making sourcing and price competition more robust. For the 1.0m and 1.25m bale formats that represent the majority of Australian round baler installations, 500mm film is the correct and more economical choice.

750mm Film: For Large-Diameter Bales

750mm film is the correct specification for large-diameter bales in the 1.8m to 2.24m range. At standard pre-stretch and 50% overlap, 750mm film covers approximately 375mm of bale surface per pass, requiring substantially fewer turntable rotations for the same layer count. For the S9000 platform baling 2.24m bales, the difference between 500mm and 750mm film in wrapping cycle time is significant: a complete 4-layer wrapping cycle on a 2.24m bale using 500mm film requires approximately 40% more turntable rotations than the same bale wrapped with 750mm film, directly extending the wrapping pause time per bale and reducing daily throughput.

The quality argument for 750mm film on large bales is separate from the speed argument. Fewer passes per layer means fewer film edge transitions on the bale surface, and film edge transitions are the primary location for incomplete overlap coverage that creates potential air infiltration pathways. The practical conclusion: use 500mm film on 1.0m and 1.25m bales, use 750mm film on 1.8m and 2.24m bales.

EverPower 9YCM-850 film wrapping machine 500mm 750mm silage film

EverPower 9YCM-850 – precision pre-stretch tension management calibrated for both 500mm and 750mm film widths across the full bale diameter range

Pre-Stretch: The Specification That Determines Film Function

Pre-stretch is the elongation applied to the film before it contacts the bale surface, expressed as a percentage of the unstretched film length. At 70% pre-stretch, each metre of unstretched film is applied as 1.7 metres of stretched film. Pre-stretch is the primary determinant of film performance on the bale, affecting film thickness, oxygen transmission rate, and film adhesion.

Standard commercial silage film is rated for 50 to 70% pre-stretch on most Australian-market products. Operating outside the rated stretch range causes problems: below the lower limit, the film is under-stretched and produces loose coverage with poor adhesion; above the upper limit, the film experiences molecular degradation that reduces its barrier properties and can cause tearing on uneven bale surfaces. The practical guidance: follow the film manufacturer’s specification for the specific product, and verify the wrapper is delivering the specified stretch ratio.

UV Stabiliser Rating: The Specification That Determines Storage Life

The UV stabiliser in silage stretch film absorbs ultraviolet radiation that would otherwise degrade the polymer chains, causing brittleness, cracking, and loss of barrier properties. The UV stabiliser rating, expressed in hours of UV exposure under standardised testing, determines how long the film maintains its integrity under outdoor storage before degradation begins.

In Australian conditions, the minimum UV stabiliser rating for outdoor-stored silage bales is 800 hours. For bales stored for 12 or more months, a UV rating of 1,000 or more hours is the appropriate specification. In high-UV environments such as inland Queensland, the Northern Territory, and northwestern NSW, 1,200-hour-rated film is the defensible choice for any bales expected to remain in outdoor storage beyond 12 months. When evaluating film products, ask explicitly for the UV stabiliser hours rating for the specific product. A supplier that cannot provide this number should be treated with caution.

Film Colour: White vs Green vs Black

White film reflects the majority of incident solar radiation, keeping bale surface temperatures measurably lower than green or black film under direct summer sunlight. For bales stored at exposed outdoor sites in inland Australia during summer, the temperature difference between white and black film can be 8 to 15 degrees Celsius at the bale surface. White film is the technically superior choice for any bale stored in high-radiation, high-temperature conditions for extended periods.

Green film is the dominant colour choice in Australian silage baling by convention rather than technical superiority. It performs comparably to white film in moderate UV conditions and cooler storage environments. For most farms in southern NSW, Victoria, and Tasmania, green film is an entirely appropriate choice at standard UV ratings.

Black film absorbs rather than reflects solar radiation, making it the worst thermal option for high-radiation, high-temperature storage sites. Its primary application is in shaded or enclosed storage environments. For outdoor storage in any Australian climate, black film is not recommended where alternatives are available at comparable cost.

Layer Count: How Many Is Enough?

The industry standard minimum for silage applications is 4 layers. At 4 layers with correct pre-stretch, a quality film provides adequate oxygen barrier for reliable fermentation and storage stability for up to 12 months under good conditions. For operations with any of the following characteristics, 6 layers is the appropriate specification:

Storage beyond 12 months – reserve bales or drought programme bales held for 18 or more months benefit from the additional barrier protection 6 layers provide.
High bird or vermin pressure – additional layers provide puncture resistance that a single outer layer cannot, particularly against cockatoo and crow attack in agricultural districts.
Legume silage crops – lucerne, vetch, and clover silage are more aerobically sensitive at feedout than ryegrass silage and benefit from the additional oxygen barrier of 6 layers.
High-UV outdoor storage – in high-radiation environments, the outer film layers degrade faster; 6 layers provides additional barrier function that remains intact when the outermost layer has experienced significant UV degradation.

Film Selection Summary

Specification For 1.0-1.25m Bales For 1.8-2.24m Bales
Film width 500mm 750mm
Pre-stretch setting 55-70% per manufacturer spec 55-70% per manufacturer spec
UV rating (standard) 800 hours minimum 800 hours minimum
UV rating (inland / 12+ months) 1,000-1,200 hours 1,000-1,200 hours
Minimum layers (standard silage) 4 layers 4 layers
Minimum layers (legumes / long storage) 6 layers 6 layers
Colour (high-UV outdoor sites) White preferred; green acceptable in temperate zones White preferred; green acceptable in temperate zones

Calculating Film Consumption: How Much to Order

Bale Format Film Width 4 Layers: Bales/Roll 6 Layers: Bales/Roll
1.0m diameter bale 500mm 75-90 50-60
1.25m diameter bale 500mm 55-70 37-47
1.8m diameter bale 750mm 50-65 33-43
2.24m diameter bale 750mm 35-45 23-30
Indicative values at 70% pre-stretch with a standard 1,800m film roll. Verify against your specific machine and film combination on the first 50-100 bales of the season.

Film Supply Through EverPower

EverPower Baling Machinery Australia Pty Ltd supplies silage stretch film through its Condell Park NSW depot in both 500mm and 750mm widths, in UV ratings appropriate for Australian operating conditions. The film supplied through EverPower is matched to the pre-stretch system specifications of EverPower wrappers, eliminating the compatibility question that arises when mixing film from unknown sources with a specific machine’s tension calibration. Pre-season bulk orders for film and net wrap can be arranged through the sales team with delivery coordination for remote locations requiring freight forwarding.

๐Ÿ“ž Talk to the Team Directly
Company:
EverPower Baling Machinery Australia Pty Ltd
Address:
27 Harley Crescent, Condell Park NSW 2200

Frequently Asked Questions

1. Can I use 500mm film on a 2.24m bale to save money?+
Not economically or practically. On a 2.24m bale, 500mm film requires approximately 40% more turntable rotations per layer than 750mm film, extending the wrapping cycle time by 4 to 6 minutes per bale. At 60 bales per day, this represents 4 to 6 hours of additional wrapping time that eliminates any film cost saving and significantly reduces daily throughput. 750mm film is the correct and more economical specification for large-diameter bales when total cost per bale including throughput impact is calculated.
2. What UV rating do I need for bales stored outdoors in Queensland?+
For outdoor storage in Queensland, particularly inland and northern regions: 1,000 hours minimum for bales stored up to 12 months, and 1,200 hours for bales stored 12 to 18 months. White film is strongly recommended over green or black for outdoor storage in Queensland’s higher-radiation regions. The solar reflectance advantage is greatest precisely where UV and heat load are highest.
3. Why do some films produce better layer adhesion than others at the same pre-stretch setting?+
Layer adhesion quality is primarily determined by tackifier concentration and formulation in the film’s outer layer. Tackifier concentration varies between film grades, with premium products typically formulated for stronger initial bond and better performance at elevated application temperatures. Economy films may use lower tackifier concentrations that produce acceptable bond in cool conditions but inadequate bond when the film surface temperature is elevated during summer wrapping. Buying film from a supplier who can disclose the tackifier specification provides better assurance of performance in Australian summer conditions.
4. How do I calculate the correct pre-season film order for my baling programme?+
Use the consumption table in this article to identify the indicative bales-per-roll figure for your bale format, film width, and target layer count. Divide your seasonal bale target by this figure, then multiply by 1.15 as a contingency buffer. Example: 400 bale target, 1.25m bales, 500mm film, 6 layers = 400 divided by 42 times 1.15 = approximately 11 rolls. Verify this estimate against actual consumption from the first 50 to 100 bales of the season. Contact EverPower with your bale format and target layer count for a specific consumption estimate based on the film products they carry.
5. What should I do if film tears during wrapping rather than stretching cleanly?+
Film tearing during application indicates one of three problems: the pre-stretch setting is above the film’s rated stretch limit; the film is cold, below 10 degrees Celsius, and has not warmed to ambient temperature; or the film roll has a manufacturing defect at a thinned section. First, check that the pre-stretch setting matches the film’s rated specification. Second, allow the roll to warm to ambient temperature before use. If tearing continues at the correct setting on a warmed roll, the roll has a defect and should be returned to the supplier with a sample of the tear section for assessment.
EverPower Baling Machinery Australia Pty Ltd
27 Harley Crescent, Condell Park NSW 2200 ย |ย  +61 2 9708 3322 ย |ย  [email protected]
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