OLI S · ball vibrators

Ball vibrators for silos, hoppers, screens and chutes

A steel ball running round a hardened track. Eight sizes from 130 grams to 1.34 kilos, 2 to 6 bar, up to 35,000 vibrations per minute, and ATEX category 2 as standard.

The material clings to the wall instead of sliding, the grains lump together on the screen, or the last layer stays behind in the bottom of the chute. The S is OLI's ball vibrator for that kind of job. Compressed air at 2 to 6 bar drives a steel ball around a hardened track, and that gives a high frequency with a small amplitude, working where the material meets the steel. The unit bolts on the outside, and no hole is drilled in the wall. Eight sizes from 130 grams to 1.34 kilos, all with ATEX category 2 for both gas and dust.

S2–6 bar90 dB(A)−20 to 150 °C0.13–1.34 kg
Tell us about your plant See the specifications
Download the datasheet Dimensions, specifications and all variants PDF · 4 pages · 109 kB
A ball vibrator S 13 seen from the front at an angle: a blue anodised aluminium body, a third wider than it is tall, with a dark round cover and a central screw in the middle of the side. On top sit two threaded ports with bright rings. At the bottom the body meets a wide foot with a round through hole at each end and an open slot outermost at each end. S 13 is cast into the foot.
The problem

Two everybody knows, and two that are the S's own

Bridging and rat-holing are familiar to anyone who has stood at a silo. What sets the rotary range apart from the rest of the programme is the next two: reducing the friction between the material and the steel, and separating material that has lumped together.

Bridge over the outlet

Bridge over the outlet

The material spans an arch across the opening and carries its own weight. The silo is full, the screw underneath runs in empty space, and nothing moves on.

Rathole through the middle

Rathole through the middle

A narrow shaft runs down through the centre while the rest stands still along the walls. It looks like it is running, but most of it stays put and gets older by the hour.

Friction and separation

Friction and separation

The material does not slide because it clings to the steel, or it sits lumped together on a screen and never gets sorted. A high frequency with a small amplitude works exactly there, in the boundary between the material and the surface.

Walkthrough

Four steps through the product

Click through: from the silo the material will not leave, to the choice between 2, 4 and 6 bar.

01 The problem

The same silo with and without ball vibratorsA silo seen from the side, divided by a vertical line. To the left of the line the material has formed a bridge across the outlet, and under the bridge it is empty; along the two cone walls a layer of material has stayed behind, and nothing comes out at the bottom. To the right ball vibrators sit on the outside of the cone walls at three heights, bolted on with the foot against the wall. None of them goes through the wall. At each unit a circular arrow shows that the force rotates, and two arcs spread into the material. The layer is gone, and a stream falls out at the bottom. The line can be dragged from side to side.Without vibratorsWith the S

Without vibrators the material carries its own weight: the bridge stands across the outlet, and a layer stays behind along the cone walls that never comes along. With vibrators the vibration travels through the steel and keeps the material moving all the way down. It is the same silo on both sides of the line.

02 The technology

Section through a ball vibrator, and the foot seen from belowAbove, the vibrator seen from the front in section. The body is almost square and stands on a wider foot. Inside the body is a circular track, and in the track a ball running round the inside of it. Two ports sit in the top face of the body: the air comes in through the left one and leaves through the right. The width of the body and the overall height of the unit are both dimensioned as A, and the thickness of the foot as D. Below is the foot seen from underneath: an elongated plate with an open slot at each end and two round holes inboard. The length of the foot is dimensioned as B, the distance between the slots as C, the depth of the foot as E and the width of the slot as F.AADCompressed air inAir outThe steel ballHardened trackThe foot from belowBCEFS 13

The compressed air comes in through the left port and out through the right. Between the two a steel ball runs round the inside of a hardened track, and the mass running round is the vibration itself. Below is the foot seen from underneath: two open slots on the outside and two round holes inboard. The ball on the drawing runs slowly enough to follow — a real S 13 reaches 250 to 375 revolutions per second.

03 The installation

Ball vibrators on a silo with the complete air supplyA silo seen from the side with ball vibrators bolted to the outside of the two cone walls at three heights. On the left stands the compressor, and from it an air line runs through four components in a row: a filter, a flow control valve, a lubricator and a 3/2 way valve. From there the line goes up over the silo and down both sides to each vibrator. At each vibrator a circular arrow shows that the force rotates, and two arcs spread into the material. At the bottom a stream of material falls out of the outlet.12345

The units bolt to the outside of the silo, and no hole is drilled in the wall. That is also why they can go onto a plant that is already running. In the supply sit a filter, a flow control valve, a lubricator and a 3/2 way valve. The lubricator is not optional here: the S wants lubricated air.

  1. The compressed air The S runs on compressed air at 2 to 6 bar. The pressure is what sets the frequency, the force and the air consumption alike.
  2. The filter The air has to be clean. The filter is the first stage between the compressor and the vibrator, and it is there on all eight sizes.
  3. The lubricator The S wants lubricated air in class 5.4.4, so the lubricator is not optional. Where oil mist is not allowed at the position, the OT turbine vibrator is the right one: it runs without lubrication.
  4. The 3/2 way valve The valve is normally closed and opens the air when the vibrator is to run. It is the last stage before the connection, and it is also what controls how long it runs at a time.
  5. The units on the silo The foot bolts to the outside, and no hole is drilled in the wall of the vessel. The force is rotary and not linear, which is why the symbol is a circular arrow and not a double arrow.

04 The choice

The working pressure
The S 13 at 2 bar with the three figuresA ball vibrator seen from the front in section with the ball in the hardened track, and below it three horizontal bars drawn to the same fixed scale: vibrations per minute, centrifugal force and air consumption at 2 bar.S 13 at 2 barPressure, frequency, force and air belong together.S 13Vibrations per minute15,000Centrifugal force32 kgAir consumption94 l/min
The S 13 at 4 bar with the three figuresA ball vibrator seen from the front in section with the ball in the hardened track, and below it three horizontal bars drawn to the same fixed scale: vibrations per minute, centrifugal force and air consumption at 4 bar.S 13 at 4 barPressure, frequency, force and air belong together.S 13Vibrations per minute18,500Centrifugal force55 kgAir consumption158 l/min
The S 13 at 6 bar with the three figuresA ball vibrator seen from the front in section with the ball in the hardened track, and below it three horizontal bars drawn to the same fixed scale: vibrations per minute, centrifugal force and air consumption at 6 bar.S 13 at 6 barPressure, frequency, force and air belong together.S 13Vibrations per minute22,500Centrifugal force87 kgAir consumption225 l/min

The figures are the S 13's. The bars are drawn to the same fixed scale on all three sheets, so the difference can be seen as a length. The relationship between the three holds across the range, but the figures do not — look your own size up in the table above.

Not which size, that is in the table above. Nor are there two versions or an option: there is one version of each size. What you actually set is the pressure, and it moves three things at once. Click between the three: the bars are drawn to the same fixed scale, so the difference can be seen and not just read.

The technology

A ball that runs round

Inside the body is a circular track of hardened and ground steel, and in the track lies a steel ball. Compressed air at 2 to 6 bar drives the ball round the inner face of the track, and the mass running round is what produces the vibration. The force is therefore not a movement back and forth along one axis, as on a piston vibrator: it is a vector that rotates. That is the difference the word rotary covers.

The frequency is high and the amplitude small. An S 8 reaches 35,000 vibrations per minute at 6 bar, and even the largest, the S 36, sits at 10,000. By comparison the pneumatic piston vibrators run between 1,200 and 6,720. That is what makes the S the right one where the problem sits in the boundary between the material and the steel, rather than deep inside a full silo.

The body is blue anodised aluminium and the covers are Ixef®, a fibre reinforced plastic that stands up to weather and hard working conditions. The unit comes in eight sizes from 130 grams to 1.34 kilos, and all eight carry ATEX category 2 for both gas and dust as standard. The air has to be lubricated, class 5.4.4, and the duty is discontinuous. If the unit has to run without stopping, tell us for how long at a time and we will find the right answer.

Data

Technical specifications

TechnologyRotary vibration, high frequency
Duty cycleDiscontinuous
Working pressure2 to 6 bar
Centrifugal force13 to 405 kg, depending on size and pressure
Frequency7,300 to 35,000 vibrations per minute
Air consumption83 to 675 l/min
Pneumatic circuitFilter, flow control valve, lubricator and 3/2 way valve N.C.
Air supply qualityClass 5.4.4, lubricated
Working temperature−20 to 150 °C
Noise levelNo more than 90 dB(A) at maximum speed
ATEXII2G Ex h IIB Tx Gb and II2D Ex h IIIC Tx Db, as standard
MaterialBlue anodised aluminium body, Ixef® covers, hardened and ground steel track
MountingFoot with four fixing points, bolted on the outside
Connection1/8″, 1/4″ or 3/8″ BSPP
Weight0.13 to 1.34 kg
The dimensions

Eight sizes

The frequency is given as the span from 2 to 6 bar, because the pressure moves it. The force is given at both ends. A is the width of the body and its overall height including the foot, B is the length of the foot, and both are dimensioned on the drawing in step 02.

Frequency in vibrations per minute at 2 to 6 bar, centrifugal force in kilograms, air consumption in litres per minute, dimensions in millimetres
ModelFrequencyForce 2 barForce 6 barAir 2 barAir 6 barABConnectionWeight
S 825,500–35,00013 kg36 kg83 l/min195 l/min50 mm86 mm1/8″ BSPP0.13 kg
S 1022,500–34,00025 kg71 kg92 l/min200 l/min50 mm86 mm1/8″ BSPP0.13 kg
S 1315,000–22,50032 kg87 kg94 l/min225 l/min65 mm113 mm1/4″ BSPP0.26 kg
S 1613,000–19,50045 kg110 kg122 l/min280 l/min65 mm113 mm1/4″ BSPP0.30 kg
S 2010,500–16,50072 kg172 kg130 l/min340 l/min80 mm128 mm1/4″ BSPP0.53 kg
S 259,200–14,00093 kg205 kg160 l/min425 l/min80 mm128 mm1/4″ BSPP0.63 kg
S 307,800–12,500151 kg321 kg215 l/min570 l/min100 mm160 mm3/8″ BSPP1.13 kg
S 367,300–10,000206 kg405 kg260 l/min675 l/min100 mm160 mm3/8″ BSPP1.34 kg

The number in the model name follows the size of the body: the S 8 is the smallest and the S 36 the largest. The sizes go in pairs on the dimensions — the S 8 and S 10 share A, B, C and D, as do the S 13 and S 16, the S 20 and S 25, and the S 30 and S 36 — but the two in each pair are not the same inside, and neither the frequency, the force nor the air consumption is. A is both the width of the body and the overall height of the unit including the foot, and B is the length of the foot. The four remaining letters are dimensioned on the drawing in step 02 and given as figures on the component card: C is the distance between the two slots, D the thickness of the foot, E its depth and F the width of the slot. The connection is a BSPP thread, and in and out share the same size on all eight. The force is the maximum centrifugal force, given in kilograms.

Components

Four things worth looking at before ordering

It is the same mechanism in all eight: a steel ball in a hardened track. What changes with the size is the dimensions and the thread. What they all share is that no hole is drilled in the wall.

Close-up of one end of the foot on a blue anodised ball vibrator: on the left a round through hole with a chamfered edge, on the right an open slot running right out to the end of the foot. The machining marks are clearly visible in the surface.

The foot A · B · C · D · E · F

The foot has four fixing points, not two. The outer two are open slots running out to the end, and the inner two are round holes. The foot sits against whatever it is bolted to, and the body stands perpendicular to that face.

Foot length, B86 to 160 mm
Slot spacing, C68 to 130 mm
Foot thickness, D12, 16 and 20 mm
Foot depth, E20 to 50 mm
Slot width, F7, 9 and 11 mm
  1. An open slot means the unit can be dropped over two bolts that are already in place, rather than having to be threaded onto them.
  2. We do not have the spacing between the two round holes. If you need it in order to pre-drill, say so and we will measure a unit.
The top face of a blue anodised ball vibrator with two threaded ports with bright rings, one at each end. An arrow is cast into the front face under each port: the left one points down, the right one up. At the bottom the edge of the dark cover is visible.

The two ports IN · OUT

There are two ports in the top face, an inlet and an outlet, and they share the same thread. The air comes in through one, drives the ball round and leaves the body through the other.

Thread, S 8 and S 101/8″ BSPP
Thread, S 13 to S 251/4″ BSPP
Thread, S 30 and S 363/8″ BSPP
In and outSame size
  1. The outlet has the same thread as the inlet, so a silencer or an exhaust hose can be screwed into it.
  2. If the air has to be taken away from the area around the unit, tell us where it should go and we will find the right arrangement.
Close-up of the round, almost black cover on a blue ball vibrator. In the middle of the cover sits a recessed screw with a hex socket in a metal ring, and at the bottom of the picture the edge of a round hole in the foot is visible.

The cover Ixef®

The track is closed by a round cover on each side. The covers are Ixef®, a fibre reinforced plastic that stands up to weather and hard working conditions, and the body around them is blue anodised aluminium.

CoverIxef®
BodyBlue anodised aluminium
TrackHardened and ground steel
Outdoor useYes
  1. The aluminium body and the anodised surface are what make the range resistant to oxidation and suitable for sitting outside.
  2. We do not have a replacement interval for the cover from OLI. If the unit has to go into a preventive maintenance plan, say so and we will ask.
Close-up of the nameplate on a ball vibrator, stuck to the blue body. It reads Batch No 29/20, Type S13, the CE mark, OLI® Medolla (MO)-Italy, www.olivibra.com, the Ex hexagon and the lines II2G Ex h IIB Tx Gb and II2D Ex h IIIC Tx Db.

The nameplate ATEX

ATEX is standard on the whole range, not an option. The marking covers both gas and dust in category 2, that is zone 1 and 21, and it sits on the unit that is delivered.

GasII2G Ex h IIB Tx Gb
DustII2D Ex h IIIC Tx Db
Category2, as standard
Zone1 and 21
  1. The temperature class is given as Tx, that is without a figure. If the unit has to sit in a zone with a requirement for a particular class, tell us which and we will come back with the answer.
  2. Zone 20, that is the inside of a vessel containing dust, is not covered by category 2.

There are no options for the S: no timer, no solenoid, no ATEX kit and no mounting plate. There is one version of each size, and ATEX comes as standard.

Application

Where the S belongs

Silo, hopper, chute and pipeThe units bolt on the outside, and the vibration runs through the steel and on into the material. No hole is drilled in the wall, so the range can also go onto a plant that is already running.
Screen and vibrating tableThis is where the two words friction and separation come from. The high frequency and small amplitude keep the material moving on the surface, so it gets sorted instead of settling.
Dry material, not dampThe range is meant for dry powders and granules: plastics, sand, ashes, cement and lime. If the material is hygroscopic, that is it draws moisture, the roller vibrator OR is the right one: it is meant for exactly that.
Filter sleeve cleaningOf the three rotary ranges the S is the only one also meant for shaking filter sleeves clean. It is the same property that makes it right on a screen: a high frequency that shakes a layer free without moving the structure.
Not for continuous runningThe duty is discontinuous. Where running has to be continuous, the pneumatic piston vibrators K and F are built for it, and they sit at 80 dB(A) against the S's 90.
FlexCore

Getting the air to every unit

A ball vibrator is nothing without compressed air at the connection. The hoses come from our own range.

Blue polyurethane hose, coiled. ARIAFORM/TPULight polyurethane hose for tools and reel systems. The softest of the three, and the one that suits the smallest 1/8″ connections. Black TPE air hose, coiled. ARIAFORM/15TPE air hose for industry and workshop. Handles water, air and oil-laden compressed air, which is exactly what the S needs. Yellow EPDM compressed air hose, coiled. ARIACORD/YELLOWRugged EPDM hose for compressed air and water, 25 bar. Weather and UV resistant, so it can live outdoors alongside a range that is itself built for outdoor use.

See the full hose range →

Blue polyurethane hose, coiled.

FlexCore

ARIAFORM/TPU

Light polyurethane hose for tools and reel systems. The softest of the three, and the one that suits the smallest 1/8″ connections.

Material
TPU
Inner diameter
6–13 mm
Working pressure
20 bar
Temperature
-30 to +80 °C

See the full product page on FlexCore →

Black TPE air hose, coiled.

FlexCore

ARIAFORM/15

TPE air hose for industry and workshop. Handles water, air and oil-laden compressed air, which is exactly what the S needs.

Material
TPE
Inner diameter
16–25 mm
Working pressure
15 bar
Temperature
-30 to +80 °C

See the full product page on FlexCore →

Yellow EPDM compressed air hose, coiled.

FlexCore

ARIACORD/YELLOW

Rugged EPDM hose for compressed air and water, 25 bar. Weather and UV resistant, so it can live outdoors alongside a range that is itself built for outdoor use.

Material
EPDM
Inner diameter
32–76 mm
Working pressure
25 bar
Temperature
-30 to +80 °C

See the full product page on FlexCore →
Further

Related

Roller vibrators · OR

The closest sibling, and the right one when the material is hygroscopic: cement, concrete, sand and foundry sand. The same mechanism, more force and 200 degrees against the S's 150.

Turbine vibrators · OT

The third rotary range. It runs without lubrication and is the one to use where oil mist is not allowed. It is also the only one of the three documented for food.

Cushioned piston vibrators · K

For continuous running and where 90 dB(A) is too much: the K is continuous duty and sits at 80. It also comes in a version that runs without lubrication.

Adjustable piston vibrators · F

When force and frequency have to be adjustable afterwards, and when the steel is hotter than 150 degrees. The F reaches 200.

Pneumatic hammers · PS

When vibration is not enough. One blow against a welded plate, where the material has set hard.

Bin aerators · VBS

For fine, dry powder in a silo, where air underneath the material is the right answer rather than a vibration in the wall.

When the powder stops

Nine chapters on why material hangs up, and what gets it flowing again.
Portrait of a technical adviser at Particulair.

Technical advice

Which size, and how many?

Tell us what the silo, hopper or screen is made of, how thick the steel is, what you handle, and how long it has to run at a time. We come back with a size, a number and a price, not with a catalogue.

Contact us Try the product selector

Download the datasheet Dimensions, specifications and all variants PDF · 4 pages · 109 kB