By Stephen Brown
Each year, the use of grain auger conveyors contributes to the total number of farm-related deaths and injuries across the nation. These augers can be dangerous if not properly selected, used, and maintained.
What is an Auger?
An auger is an implement with helical flighting driven by a power source to rotate the flighting around a center shaft and carry material from one end of the auger to the other. Augers can be used in all directions: horizontal, angled, and vertical. Depending on the application and volume of grain that needs conveyed, multiple auger configurations may be used.
An auger consists of four main parts. The first part is the drive motor which can be either an electric motor, hydraulic motor, gasoline engine, or PTO (Power Take Off). Secondly, the auger has a center shaft serving to create a center point for the helical flighting to be anchored to and rotated around. Next is the helical flighting itself which forms a spiral that when rotated, conveys the loose particulate/fluid material. Finally, the auger shaft and flighting are typically located within either a tube or trough depending on the application so that the loose material is transported between the flighting and retained by the tube/trough walls, allowing for material motion.
Figure 1. Common parts of an auger system
Typical Auger Uses
Auger conveyors are used throughout the grain production process. When grain is harvested, an auger transports it from the harvester to the truck for transporting. Other augers transport the grain from trucks into the grain bins where it will be dried and stored. Occasionally, during the drying process, grain can be moved between bins which is usually done by an electric auger. After the grain is dried, augers are also responsible for transporting it from the bins back to the trucks.
Types of Augers
Sweep Auger
A sweep auger is designed to finish removing grain from the bin once the grain level is too low to continue flowing by gravity. This auger is designed with a trough rather than a fully enclosed tube so one side remains exposed to the grain. The sweep auger is attached to the bottom center of the bin where the main sump is located and extends out to the bin wall. As shown in Figure 2, it then rotates around the bin to pull any excess grain from the edges to the center unloading sump.
Figure 2: Sweep auger inside a grain bin
Portable Auger
Portable augers are a popular tool used when working with grain and they come in various lengths and diameters depending on the task. Some augers are small enough to be carried while others have wheels that allow them to be towed to a specific site. Their ability to be transported makes them very appealing and can often save money and space when compared to stationary systems.
Aside from being portable, these auger systems operate in a similar fashion to others. However, unlike the sweep auger, the portable upright augers use a fully enclosed tube for the shaft and flighting to rotate in rather than a trough. Figure 3 shows a portable upright auger that is powered by a Power Take Off (PTO) shaft from the rear of the tractor.
Figure 3: Portable PTO driven auger filling a grain bin
Auger Conveyor Hazards and Safety
Auger conveyors account for many farm-related injuries and fatalities on an annual basis. Electrocution and entanglement are among the most common injuries associated with auger conveyors.
Electrocution
When transporting augers, the auger needs to be lowered to prevent the possibility of coming into contact with overhead power lines. Even then electricity can arc from power lines to an auger conveyor without direct contact, so it is important to be aware of power lines locations and plan your route before traveling. For electric-motor driven grain augers, electricity safety can lessen the risk of electrocution and fires. Basic electrical safety steps are included below:
- Ensure all warning labels (Figure 4) are in place, visible, and being followed.
- Check wires between circuit breaker and auger motor, and internal motor wiring for wear and repair if needed
- Use Ground-Fault Circuit Interrupters (GFCIs) to mitigate unintentional grounding.
- Over-current protection such as circuit breakers and fuses can prevent overheating and fires.
- Ensure there are no exposed (e.g., bare, unsheathed, etc.) wires anywhere when checking your electric system including power line, circuit breaker, and equipment wiring
- Lockout/Tagout equipment before servicing.
- Completely lower portable augers before transporting to avoid contact with power lines.
- Identify and map out the safest route before transporting
Lockout/Tagout is the process of physically locking a machine or equipment in the off position and tagging it with the serviceman’s name, to prevent accidental energizing of the machine.
Figure 4: Warning decal located on the bin electrical box
Entanglement
Entanglements are severely traumatic life-threatening injuries that often result in broken bones, loss of limb, or even death. Properly guarded augers and PTOs can be the difference between a close call and a fatality. Ensure that all shields and guards are securely fastened in place and in good condition. When working around equipment, following these safe practices:
- Guards should be free of holes, dents, or deformations which can decrease effectiveness.
- Keeps hands, feet, hair, and clothing away from moving parts of machinery.
- Avoid wearing loose clothing and jewelry.
- Lockout /Tagout equipment before servicing equipment or entering a bin.
- Shutdown the equipment prior to doing any type of maintenance.
Entrapment/Engulfment
Grain entrapment and engulfment may also occur when using augers. When an auger is powered on, the grain begins flowing down the channel and goes out from underfoot, pulling the individual further and further into the grain. Then the grain flowing from above collapses in surrounding and engulfing the individual. At unload speeds of just 25 metric tons per hour, (925 bushels per hour) it only takes about 30 seconds for an individual to become entrapped up to their shoulder level (Issa and Field, 2017). Before entering a loaded grain bin, consider referencing the following: OSHA CFR 1910.272 and ANSI/ASABE S624. Some key safety points from these documents are below:
- Ensure all warning labels (Figure 5) are present and visible.
- Use a lifeline, full-body safety harness, and have someone observe activity inside the bin from outside the bin.
- Lockout/Tagout all power sources before entering the bin.
- Never enter a bin while an auger is running.
- Never enter a grain bin alone.
Figure 5: Warning label located on the grain bin door
Work Areas
When using machinery of any kind, especially augers, it is important to establish safe working areas. Work areas should only be entered by authorized and trained personnel with proper Personal Protective Equipment (PPE). During times of operation, it is helpful to have barriers and signage in place to deter others from entering without permission. Furthermore, these areas should be well maintained to minimize the likelihood of an incident occurring. Ways to create a safe work zone include the following:
- Train workers on proper PPE for the task such as hand, eye, ear, and foot protection.
- Use barriers to deter unauthorized visitors.
- Use signs to warn others of hazards that could be present.
- Keep area clear of slip, trip, and fall hazards.
- Ensure equipment is working properly and all safety devices and guards are in place.
- Train operators on emergency shut-down procedures.
- Keep an emergency contact list in an easily accessed location.
Conclusion
Auger conveyors are considered one of the most helpful, yet hazardous pieces of equipment found on a farm. Misuse and lack of equipment maintenance can increase the chance of an incident occurring that could result in a lost-time injury or worse, a fatality. By addressing these issues and properly using equipment these types of incidents can be prevented while efficiently completing tasks.
This work was supported by a grant from the Northeast Center for Occupational Health and Safety: Agriculture, Forestry, and Fishing (NIOSH grant #2U54OH007542).
Source : psu.edu