Sorting Without a Motor
A pile of mixed ground looks like one material, but to a crusher, a conveyor, or a landscaper it is really several: boulders, cobble, gravel, and fines, all tangled together. The oldest way to separate them is also the simplest, which is to give the pile a slope and let gravity do the sorting. A heavy-duty grizzly static rock screen is that idea built in steel: a sloped deck of parallel bars where small pieces fall through and large ones slide off the end. There is no motor, no belt, and nothing that wears except the bars themselves.
Why the Bar Spacing Is the Real Decision
Spacing sets the cut. Whatever is smaller than the gap between bars falls through, and whatever is larger rides over. On this rock screen the deck bars bolt on and adjust from 1 inch to 5 inches, so one machine can make several different cuts. The right gap is not a matter of taste, because the next step in the process sets it. If a crusher downstream chokes on anything above a certain size, the spacing should keep that oversize out. If a landscaper wants clean fill, the gap decides how much stone stays in the pile.
- Narrow bars for cleaner fill and finer material
- Wide bars to remove only the biggest boulders
- Middle settings for pre-sorting before crushing
What the 37 Degree Slope Does
The deck sits at 37 degrees, a steep angle on purpose. Too flat and material rests on the bars, bridging the gaps and blocking the screen. Too steep and everything races across before the small pieces have time to drop. At this angle debris slides off efficiently, and the diamond-shaped bars help the deck clean itself, because the angled profile sheds stones that would otherwise wedge between parallel bars and stay there. A self-cleaning deck matters more than it sounds, since blocked bars are the most common reason a screen stops sorting well.
Loading It the Right Way
A static screen works only as well as the way it is fed. The loading area measures 12 feet by 9 feet and the load capacity is 5000 lb, so an excavator or wheel loader can drop bucketfuls onto the upper end and let the material travel down. Feed it steadily instead of in one heap. A single big dump buries the bars, and the small pieces on top can no longer reach the gaps. Wet clay is the usual troublemaker because it clings together and rides over the bars as one lump, so expect a lower yield from damp ground and dry material.
Reading the Pile Before Choosing a Cut
Before setting the bars, look at what is actually in the pile. Take a few bucketfuls, spread them on the ground, and judge how much is oversize, how much is mid-sized stone, and how much is fine material that will fall through any setting. If most of the pile is boulders, a wide gap saves time. If most of it is usable stone with a few large pieces mixed in, a tighter gap pulls out the problem rocks and leaves the rest. Damp ground changes the picture, because clay clings to stones and makes them look larger than they are.
Stockpiles and Traffic Around the Screen
A screen produces two piles, one under the deck and one at the discharge end, and both need room to grow. Plan the site so the loader can reach the feed end, the fines pile can be moved without driving across the oversize pile, and water runs away from both. Leave a turnaround for trucks that haul the finished material, and keep the discharge side clear of walkways. A tidy layout keeps the machines moving, which matters more than the screen itself once the day gets busy.
Keeping the Deck in Shape
A static screen asks very little, but it does ask for a few minutes between jobs. Check the bolts on the deck bars, since vibration and impact work them loose, and look for bent or worn bars that no longer hold their spacing. Inspect the welds on the frame, touch up bare steel to slow rust, and clear packed material from underneath so water cannot sit against the structure. A short walk-around before each job costs far less than an unplanned stop in the middle of one.
The Frame Underneath
A screen takes an impact every time a bucket lands, so frame strength decides how long the deck stays true. This one is built from 4 inch by 4 inch I-beam with a powder-coated steel structure, and it is described as quick to assemble. Set it on a firm, level base so that the slope is the one you intended. A leg that settles into soft ground changes the angle, and a changed angle changes the cut, which is why a rock screener should be checked with a level at the start of each job and again after any heavy rain that could soften the ground beneath the legs.
Working Around a Loaded Screen
Never reach onto the deck or climb it to free a jam. Rocks that stop sliding can release without warning, so use a bucket edge or a long tool from outside the work zone, keep the area below the discharge point clear, and hold spectators beyond the reach of anything that might roll. Wear eye protection and a hard hat as site rules require, and agree on hand signals between the loader operator and anyone on the ground. A calm, repeatable routine is a sound protection on a site where rock moves under its own weight.
Where Pre-Screening Is Heading
Crushing and processing costs keep climbing with fuel and wear, and every oversize rock fed into a crusher shortens the life of the machine and slows the line. That is why pre-sorting oversized material before crushing, the job a scalping screen does, has become a common first step on many aggregate, demolition, and recycling sites. Landscapers use the same logic on a smaller scale to turn a mixed load of excavated ground into usable fill and removable oversize, and operators who run a screen regularly often find that the biggest saving is the time they no longer spend picking rocks out by hand.
Putting the Pieces Together
Think of the whole system as three decisions: how wide the bars sit, how steadily the screen is fed, and how the piles at each end are managed. TMG Industrial builds the RS12 with the 1 inch to 5 inch bar range and the 12 foot by 9 foot loading area, and the same line includes a smaller RS10 for tighter sites.
