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Large Poly Bulk Feed Bins — Overview
These Large Poly Bulk Feed Bins are the ideal solution for storing and managing corn, soybeans, and other granular materials on farms and ranches. Built from UV-treated, 3/16"-thick high-density polyethylene (HDPE), these bins never rust or corrode. The translucent walls let you monitor grain levels at a glance — no guesswork required. The two-piece upper/lower section design makes assembly significantly faster than traditional metal grain bins, while smooth interior walls and hopper surfaces reduce grain bridging and eliminate the through-rivets and seams that cause clogging.
Optional Auger Kits deliver a complete mechanical unloading system, including the auger, motor, mounting hardware, powder-coated motor box, belts, belt guard plates, and drop spout — everything needed for seamless, hands-free grain dispensing.
Every Poly Grain Bin Includes
- Ground-operated, vented bin lid (22" diameter)
- Ladder on 1.5-ton capacity and above
- Choice of bottom slide valve: 0°, 30°, or 45°
- Caulk for sealing upper and lower sections
- Steel frame and legs with baked-on powder-coat finish
- UV-stabilized, high-impact HDPE construction
- Pro-rated 5-year manufacturer's warranty
Poly Grain Bin Size Chart
| Ton Size | Cubic Feet | Bushel Capacity | Height | Diameter | Weight |
|---|---|---|---|---|---|
| .5 (bottom only) | 30 | 24 | 78" | 52" | 180 lbs. |
| .8 | 40 | 32 | 10' 10" | 50" | 300 lbs. |
| 1.5 | 75 | 60 | 9' 6" | 74" | 470 lbs. |
| 2.5 | 130 | 104 | 11' 5" | 74" | 500 lbs. |
| 3.5 | 180 | 144 | 13' 5" | 74" | 540 lbs. |
| 4.5 | 220 | 176 | 12' 6" | 96" | 800 lbs. |
| 6.5 | 325 | 260 | 16' | 96" | 850 lbs. |
| 8.5 | 425 | 340 | 19' 6" | 96" | 950 lbs. |
Key Features of the Poly Grain Bin
- Translucent walls — see grain level without opening the bin
- High-impact, UV-stabilized polyethylene rated for outdoor use
- No rust or corrosion — ever
- Smooth walls reduce bridging and simplify cleaning
- Faster assembly than traditional metal grain bins
- Baked powder-coat finish on all steel frame components
- Ground-operated, vented lid relieves moisture buildup
- Ladder with anti-slip foot guards (1.5-ton and larger)
- Bottom slide valves in 0°, 30°, and 45° angles included
- Optional 4" or 6" diameter augers for mechanical unloading
- Pro-rated 5-year manufacturer's warranty
Foundation & Installation Guidelines
For safety, all poly grain bins should be anchored to a concrete pad — whether installed indoors or outdoors. Anchored legs provide critical stability, particularly for outdoor bins exposed to wind. An empty or lightly filled bin presents a large surface area that wind can catch, increasing the risk of tipping. A 5½"-thick reinforced concrete pad is recommended. Each leg is secured with concrete anchor bolts through each foot. Refer to the foundation diagram below for anchor bolt patterns and recommended pad dimensions.
Poly Feed Bin Design & Dispensing System
Every poly grain bin features a 22" diameter ground-operated lid — just pull the rope to open and fill. A 16" opening in the bottom cone feeds into the slide valve system for controlled dispensing. All bins include a choice of three bottom-mounted slide valve angles (0°, 30°, or 45°), each made with a galvanized plate and guide system for smooth, manual flow control. Augers in 4" and 6" diameters are available in lengths from 6' to 21' for mechanical unloading.
Ground Clearance — Bottom of Slide Valve to Ground
| Collar (Boot) Angle | .8 – 3.5 Ton Bins | 4.5 – 8.5 Ton Bins |
|---|---|---|
| 0° (Straight) | 23" | 17.5" |
| 30° | 20" | 14.75" |
| 45° | 19.5" | 14.5" |
Bin Leg Configuration
| Bin Size (tons) | Number of Legs |
|---|---|
| .8 – 3.5 | 4 legs |
| 4.5 – 8.5 | 6 legs |
Grain Bin Attachments & Accessories
The bottom of every poly bulk feed bin is engineered to accept manual slide valves and auger unloader boot assemblies. All accessories are manufactured from the same high-impact HDPE for a seamless, corrosion-free system.
Slide Valves — 0°, 30°, and 45° Options
The straight (0°) slide valve provides maximum ground clearance beneath the bin. The 30° and 45° angled valves reduce under-valve clearance but direct flow away from the bin legs for easier auger placement. All three are included as a choice with every bin purchase.
Auger Boots (Unloader Boxes)
The auger unloader boot is a white HDPE section that mounts below the slide valve, creating a sealed transition from bin to auger. Available for 3.5", 4", and 6" diameter augers. The auger itself is not included with the boot assembly — it is shown for reference only.
Optional Auger Kits for Mechanical Grain Unloading
For farms and ranches managing large herds, the optional auger kits provide fast, mechanical grain transfer directly into feed trailers or storage vehicles. Augers are available in 4" and 6" diameters and lengths from 6' to 21'. Each complete kit includes the auger, motor, mounting hardware, powder-coated motor box, belts,
Poly Bulk Feed Bin Sizes & Options
These versatile, durable poly bulk feed bins are available in a full range of sizes to match any farm or ranch storage requirement. Every size features translucent HDPE walls so you can monitor remaining feed levels at a glance — no climbing, no guessing. All bins are compatible with optional auger kits and slide valves, and each includes a 22" diameter lid for fast, easy top-filling.
The .5-ton hopper bin is designed for indoor use and does not include a lid — ideal for dispensing smaller feed quantities at one time. All bins from .8-ton and larger include a ground-operated vented lid for safe outdoor use.
.5-Ton Indoor Hopper Bin (No Lid)
.8-Ton and 1.5-Ton Poly Grain Bins — Outdoor Use with Lid
.8-Ton Bulk Bin — 40 cu ft | 32-bushel capacity | 16" clearance under slide valve
2.5-Ton and 3.5-Ton Poly Bulk Feed Bins
4.5-Ton and 6.5-Ton Poly Bulk Feed Bins
6.5-Ton and 8.5-Ton Large Poly Grain Bins
8.5-Ton Poly Bulk Bin — Fully Assembled
Grain Bin Auger Discharge Heights by Length
Use the diagrams below to determine the correct auger length for your setup. Discharge height varies based on auger length and the boot angle installed on the bin. Both 30° and 45° boot configurations are shown.
30° Boot — Auger Discharge Heights
45° Boot — Auger Discharge Heights
Poly Grain Bin Components — Detailed Views
Vented Lid
The ground-operated vented lid allows moisture and pressure to escape, protecting stored grain from humidity buildup. The 22" hinged lid is operated by a pull rope from ground level — no climbing required to open or close.
Assembled Bin — All Parts Labeled
Ladder Assembly — 8.5-Ton Poly Grain Bin
On bins 1.5-ton and larger, a steel exterior ladder with anti-slip foot guards provides safe access to the top fill opening. The ladder bolts directly to the bin's steel frame for solid, permanent attachment.
Mounted Slide Valve — Bottom Hopper View
The slide valve mounts directly to the bottom of the hopper cone. Shown here on a 45° collar, it is ready either to dispense grain manually or to accept an auger unloader boot for mechanical transfer. Slide the galvanized plate to control flow — open, throttle, or close with a single hand movement.
Grain Bin Footing & Foundation Diagram
Poly Feed Bin Assembly Manuals & Instructions
Download the correct manual for your bin size before beginning assembly:
Grain Bin Auger Unloader — Mechanical Feed Transfer
When feeding large herds or loading transport vehicles, the grain bin auger unloader provides fast, mechanical feed transfer directly from the bin. The auger unloader box accommodates 3.5", 4", and 6" diameter augers and creates a clean transition from the bin's hopper to the auger intake. Below are photos showing the auger box alone and installed on the slide valve collar.
⚠ Important: The auger kit motor does not include a hardwired plug. Electrical connection must be made by a qualified electrician.
Feed Bin Auger Unloader Box
Grain Bin Auger — Full Assembly
10 Advantages of Poly Grain Bins Over Galvanized Metal Grain Bins
Farmers and ranchers switching from traditional galvanized steel bins to high-density polyethylene (HDPE) poly grain bins consistently report lower maintenance costs, longer service life, and better grain protection. Here's why:
1. Corrosion-Free for Life
HDPE is completely immune to rust and chemical corrosion — critical in humid climates or when storing chemically treated feed supplements. Galvanized metal bins corrode over time, eventually contaminating stored grain and compromising structural integrity.
2. High-Impact Durability
Flexible polyethylene absorbs impacts from farm equipment without denting or cracking. A dented metal bin creates stress points that accelerate corrosion and weaken the structure permanently.
3. Lightweight — Easy to Move & Install
Poly bins weigh significantly less than equivalent metal bins, making delivery, site positioning, and any future relocation far easier — often without heavy equipment.
4. No Heat Conduction
Metal bins act as heat conductors, raising internal temperatures in summer that can spoil grain or degrade feed quality. HDPE's low thermal conductivity keeps internal temperatures more stable year-round.
5. Less Condensation — Less Spoilage Risk
Metal surfaces condensate heavily as temperatures fluctuate between day and night. Poly walls resist condensation buildup, dramatically reducing the mold and moisture risk that ruins stored grain and feed.
6. Near-Zero Maintenance
No rust inhibitor treatments, no dent repairs, no re-coating, no seam inspections. Poly bins clean quickly with standard cleaning agents and require virtually no routine maintenance over their service life.
7. Lower Long-Term Cost
While up-front pricing varies by size, the combination of minimal maintenance, longer service life, and grain protection in harsh outdoor environments makes poly bins a better long-term value than galvanized metal alternatives.
8. Built-In UV Protection
UV stabilizers are compounded directly into the HDPE material — not just a surface coating — providing permanent resistance to sun-induced degradation, brittleness, and color fading, even after years of direct outdoor exposure.
9. Faster, Simpler Assembly
The two-piece upper/lower cone design bolts together at a single mid-point seam. Compare that to metal bins requiring dozens of bolts across multiple ring sections — poly bin assembly takes a fraction of the time and labor.
10. Quieter Operation
Grain cascading onto metal walls creates significant noise that can stress nearby livestock. Poly bins absorb sound, keeping filling and dispensing operations dramatically quieter — a genuine animal welfare benefit in barn and pen environments.