This is one of the most basic types of drag chain conveyor. The chain lies flat on its side as it slides on tracks made of angle iron with UHMW wear surfaces, to reduce friction. Steel cross angles are bolted between the two chains at regular intervals, which slide on a solid conveyor bed and pull material along.
This open-frame style belt works well for metering material being fed out of a hopper. The chain belt is guided around both ends of the conveyor on sprockets. The sprockets at the discharge end of the conveyor grab the chain as the shaft and sprockets are turned by a motor with a reducer.
Common Drag Chain Conveyor Uses
Beltless drag chain conveyors with steel flights are commonly built as:
Conveyor Orientation Options
Remcon can build drag chain conveyors in many different orientations, depending on the layout requirements. We can also build two separate conveyors that run in series — to simplify installation, separate clumps better, or use two different types of conveyors (for example, a roller chain feeding a slider bed). Other options may be available, depending on the application.
All of these orientation options can be installed both in-ground (in a pit) or above ground.
Conveyor Features
Structural Steel Conveyor Frame
Heavy-duty open frame construction from structural shapes and formed plate at elbows, braced and reinforced for rigidity in all places and completely shop fitted and welded. The conveyor frame is specially designed to allow more access between upper and lower belts and includes special expanded maintenance openings.
Conveyor Alignment
Remcon conveyors are shop fabricated in the longest sections practical (up to 40 ft.). Adjoining sections are aligned accurately with each other in the shop as they are fabricated. The entire conveyor is aligned (and leveled) a second time during installation, to prevent the belt from wandering and wearing into the side of the conveyor.
Conveyor Bed
The solid bed surface that the open-frame style belt slides on is replaceable and is constructed in sections that are proportionally sized to be easy to handle. Standard bed construction is 1/4" steel plate, but other options such as hardened plate or UHMW-covered steel are also available.
UHMW Plastic Wear Surfaces on Impact Beams
1/2" thick x 6" wide black reprocessed UHMW polyethylene plastic is attached to the conveyor impact beams. (Reprocessed UHMW is used due to the improved wear properties achieved by the cross-linking that happens during the production process.) When sufficient load is applied to the belt to cause the impact channels to flex, the impact shoes ride on the UHMW wear strips rather than directly on the steel impact beams. The plastic is attached with bolts, is easily replaced, and has slotted holes that allow for thermal expansion to prevent buckling in warm weather.
Drag Chain Tracks
Steel angle iron with 1/2" thick x 6" wide black reprocessed UHMW polyethylene plastic wear surface provides a smooth, low-friction, wear-resistant surface for the drag chain to slide on. The plastic is attached with bolts, is easily replaced, and has slotted holes that allow for thermal expansion to prevent buckling in warm weather.
Hold-Down Guides
Remcon's special UHMW hold-down guides guide the drag chain up or over curves (if there are angle changes in the conveyor) and are built to be easily replaced if needed.
Leg Height and Leveling Adjusters
Conveyor legs are equipped with threaded height adjusters for fine-tuning the height and for leveling the conveyor accurately.
Remcon Belt Take-Ups
Remcon's cantilevered telescoping tube style take-ups, with manual screw adjustment, offer the following advantages:
- Cleaning access. The support tubes are positioned to provide access to the area between the upper and lower belts, for cleaning and inspection of the tail pulley on slider bed conveyors, or the tail sprockets and shaft of chain belt conveyors.
- Replaceable parts. The bearings are commonly available pillow block style. The threaded working parts of the take-up are commonly available from local fastener or hardware stores, and are replaced easily.
- Take-up travel. Generous length of take-up travel: 12" on the shorter conveyors and up to 18" on the longest. On slider bed conveyors, the belt is cut so that the majority of the take-up is used for ease of belt installation, repair, and replacement, since good quality belts with polyester carcasses have virtually no stretch after initial tensioning, and in some cases will shrink slightly.
- Ease of adjustment. Tracking and tension adjustments are made with one wrench, with no need to loosen and re-tighten the bearing attachment bolts. The moving parts of the take-up have generous amounts of clearance, to prevent binding in the frame or against the bearings (side load) as the take-up moves through its full range.
- Versatility. Remcon take-ups will accommodate almost any brand of bearing, in the most common pillow block style.
Tracking Adjustments on Both Ends of Conveyor
Additional belt tracking adjustments are provided for the non-take-up end of each conveyor, for ease of tracking adjustments.
Drive Method: Parallel Gear, Shaft-Mounted, Torque Arm Gear Reducers (Dodge Torque Arm II)
These reducers have been used almost exclusively in the sand, rock, gravel, and mining industries for many years, and are well proven. Remcon has used them since 1990, with good success. The new generation has been re-engineered throughout with features designed to improve performance, extend service life, and reduce maintenance. Remcon normally configures these reducers to be driven by a separate motor by v-belts, using different combinations of sheaves for additional speed reduction.
The advantages of the Dodge Torque Arm II shaft mount reducer with v-belt drive:
- Low maintenance. There are no chains to oil, tension, or shorten and reconnect.
- Ease of adjustment. Rather than moving the entire gearbox and motor to adjust chain tension, adjusting the Dodge Torque Arm II reducer only requires opening the hinged door on the belt guard, loosening the two lock nuts, and turning the turnbuckle by hand.
- Fewer wear parts. There are no sprockets or chain to wear out. Although v-belts will wear out, they commonly do not wear out until they are protecting the conveyor from jamming, if it jams (see the following item). They are inexpensive and easy to replace. V-belt sheaves last much longer than drive chain sprockets and drive chain.
- Jamming protection. The need for mechanical shear pins is eliminated. The motor drives the reducer by v-belt(s). If the conveyor jams, the v-belt slips, preventing the jam from causing damage to the conveyor. As the v-belt is slipping, it typically makes a loud squealing noise that draws attention to the problem. If the conveyor is not turned off, the v-belt will eventually be ruined, and there will be nothing driving the jammed conveyor. The cost of replacing the v-belt is typically $20 or less. Replacing the belt involves opening the hinged belt guard door, loosening the turnbuckle, and slipping the new belt on. If the conveyor is prone to jamming (for example, wrong product or too much product), the v-belt can be kept looser than normal to minimize the potential for damage. In the past 12 years that we have used these reducers, we are unaware of any Remcon conveyor equipped with them that suffered damage resulting from jamming. As additional jamming protection, an electronic shear pin may be added to the electrical system.
- Parallel gears. The gears are parallel, rather than right angle. Parallel gears are more efficient and produce less friction.
- Operating and maintenance convenience. When working on a conveyor — doing maintenance, un-jamming product, or diagnosing problems — there is often a need to move the belt a short distance forward or backward. This is impossible electrically, since the power should be locked out at this time. But it can be accomplished easily and safely without power when using a shaft-mounted reducer, by turning the spokes on the input sheave by hand.
- Excellent availability. Unlike other reducers, Dodge Torque Arm II reducers are so commonly used in other industries that they are quite often in stock at many local dealers, and are almost always available somewhere in the country. Other brands (Link, Browning, etc.) may also be substituted without modification.
- Separate motor. The motor is mounted separately from the reducer, and is connected only by v-belts. Therefore, any brand of motor can be used, and a motor breakdown does not affect the reducer, or vice-versa.
- Ease of changing reduction ratios. Reduction ratios of up to 5 to 1 are easily obtained from the motor-to-reducer v-belts and sheaves. These ratios are easily changed by swapping out sheaves, which is more difficult and expensive with a drive chain and sprockets.
Variable Frequency Drive (VFD)
A VFD can be a very worthwhile component to have on a conveyor, and is especially recommended on chain belt conveyors. VFDs offer:
- Soft start — decreases wear and tear on the motor and other drive parts
- Jam protection — replaces old technology (shear pins, clutches, etc.) and works better
- Many other programmable settings for speed, acceleration, deceleration, and more
Belt Specifications
Below are some standard belt specifications available for this type of conveyor. Many of the components can be adjusted to suit your needs.
- Belt width — 24" to 72"
- Cleats — 3 x 3 x 1/4" angle iron (other options also available)
- Chain — 4" pitch or larger, welded; several options available depending on the type of material and the load on the belt
Maintenance & Safety Features
Remcon's drag chain conveyors are designed to allow the safest and easiest access to maintenance areas, to ensure a smooth running operation.
Enlarged Maintenance Access
Special open frame design maximizes access between the upper and lower belts and includes special expanded maintenance openings.
Hinged Guards for Drive Components
Remcon's standard guards include a hinged door that provides convenient access for inspection and maintenance without removing a guard. For conveyors that have insufficient clearance for a hinging door at the drive, the door — rather than the entire guard — is unbolted to gain access.
Self-Cleaning Belt Return Chutes & Guarding
The entire underside of the conveyor, from the discharge to the floor, is guarded for safety and cleanliness. Debris that clings to the belt falls into the chutes (rather than onto the floor), then slides down the chutes, which are free of catch-points. It then collects in a guarded collection point at floor level (and outside of the pit, if there is one). The chutes are easily removed for maintenance.
Debris Clean-Out Door
Debris that slides down the return belt chutes is collected in this guarded area. The door provides convenient cleaning access.
Emergency Stop System
Cable-pull switch with required cable and rigging.
Pit Deckplate Features
Remcon also manufactures deck plates and supporting framework custom designed to fit each pit conveyor. We offer a system that allows the easiest access to the inside of the pit for maintenance, while keeping the loading floor safe and secure during operation.
Deck Plates
1/2" thick plate, with 3 x 3 x 3/8" angle stiffeners, 5 feet typical length. Pit deck stops are welded to the underside of the deck plates to prevent the plates from being slid apart by a skid steer machine. They also act as guides to allow removal and re-installation of the plates by one person on a forklift, using the lift-out deck plate handles.
Lift-Out Deck Plate Handles
These heavy-duty handles are inserted into special holes in the center of the plates. A forklift is then used to remove and re-install the plate, all by one person.
Deck Plate Supports
Steel tube, 3 x 3 x 1/4" or larger, with one end welded to the steel embedded in the top of the concrete pit wall (curbing angle) and the other end welded to the conveyor. These tubes are installed underneath the 1/8" gaps between all the deck plates, and are spaced 4 to 5 feet apart. The deck support tubes serve the following functions:
- Provide additional support for the deck plates, to bear the load of bucket loaders, etc.
- Block small debris from falling through the small gaps between plates and into the pit
- Act as strong stops to keep the removable pit plates locked into place
- Protect the conveyor from damage by bucket loaders, by tying the conveyor into the concrete pit wall every 5 feet
- Provide a positive means of locking the conveyor into very accurate alignment despite all the abuse it normally receives — a misaligned conveyor results in excessive wear to both the belt and the rails that the belt rides on
We specialize in custom designed and fabricated equipment and can work with you to design a solution that will work well for your needs. Contact us to discuss options or to get a quote.
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