rock crusher for sale small

jaw crusher working principle

A sectional view of the single-toggle type of jaw crusher is shown below.In one respect, the working principle and application of this machine are similar to all types of rock crushers, the movable jaw has its maximum movement at the top of the crushing chamber, and minimum movement at the discharge point. The motion is, however, a more complex one than the Dodge motion, being the resultant of the circular motion of the eccentric shaft at the top of the swing jaw. combined with the rocking action of the inclined toggle plate at the bottom of this jaw. The motion at the receiving opening is elliptical; at the discharge opening, it is a thin crescent, whose chord is inclined upwardly toward the stationary jaw. Thus, at all points in the crushing chamber, the motion has both, vertical and horizontal, components.

It will be noted that the motion is a rocking one. When the swing jaw is rising, it is opening, at the top, during the first half of the stroke, and closing during the second half, whereas the bottom of the jaw is closing during the entire up-stroke. A reversal of this motion occurs during the downstroke of the eccentric.

The horizontal component of motion (throw) at the discharge point of the single-toggle jaw crusher is greater than the throw of the Dodge crusher at that point; in fact, it is about three-fourths that of Blake machines of similar short-side receiving-opening dimensions. The combination of favorable crushing angle, and nonchoking jaw plates, used in this machine, promotes a much freer action through the choke zone than that in the Dodge crusher. Capacities compare very favorably with comparable sizes of the Blake machine with non-choking plates, and permissible discharge settings are finer. A table of ratings is given.

The single-toggle type jaw crusher has been developed extensively. Because of its simplicity, lightweight, moderate cost, and good capacity, it has found quite a wide field of application in portable crushing rigs. It also fits into the small, single-stage mining operation much better than the slower Dodge type. Some years since this type was developed with very wide openings for reduction crushing applications, but it was not able to seriously challenge the gyratory in this field, especially when the high-speed modern versions of the latter type were introduced.

Due to the pronounced vertical components of motion in the single-toggle machine, it is obvious that a wiping action takes place during the closing strokes; either, the swing jaw must slip on the material, or the material must slip along the stationary jaw. It is inevitable that such action should result in accelerated wear of the jaw plates; consequently, the single-toggle crusher is not an economical machine for reducing highly abrasive, or very hard, tough rock. Moreover, the large motion at the receiving opening greatly accentuates shocks incidental to handling the latter class of material, and the full impact of these shocks must be absorbed by the bearings in the top of the swing jaw.

The single-toggle machine, like the Dodge type, is capable of making a high ratio-of-reduction, a faculty which enables it to perform a single-stage reduction of hand-loaded, mine run ore to a suitable ball mill, or rod mill, feed.

Within the limits of its capacity, and size of receiving openings, it is admirably suited for such operations. Small gravel plant operations are also suited to this type of crusher, although it should not be used where the gravel deposit contains extremely hard boulders. The crusher is easy to adjust, and, in common with most machines of the jaw type, is a simple crusher to maintain.

As rock particles are compressed between the inclined faces of the mantle and concaves there is a tendency for them to slip upward. Slippage occurs in all crushers, even in ideal conditions. Only the particles weight and the friction between it and the crusher surfaces counteract this tendency. In particular, very hard rock tends to slip upward rather than break. Choke feeding this kind of material can overload the motor, leaving no option but to regulate the feed. Smaller particles, which weigh less, and harder particles, which are more resistant to breakage, will tend to slip more. Anything that reduces friction, such as spray water or feed moisture, will promote slippage.

Leading is a technique for measuring the gap between fixed and moveable jaws. The procedure is performed while the crusher is running empty. A lead plug is lowered on a lanyard to the choke point, then removed and measured to find out how much thickness remains after the crusher has compressed it. This measures the closed side setting. The open side setting is equal to this measurement plus the throw of the mantle. The minimum safe closed side setting depends on:

Blake (Double Toggle) Originally the standard jaw crusher used for primary and secondary crushing of hard, tough abrasive rocks. Also for sticky feeds. Relatively coarse slabby product, with minimum fines.

Overhead Pivot (Double Toggle) Similar applications to Blake. Overhead pivot; reduces rubbing on crusher faces, reduces choking, allows higher speeds and therefore higher capacities. Energy efficiency higher because jaw and charge not lifted during cycle.

Overhead Eccentric (Single Toggle) Originally restricted to sampler sizes by structural limitations. Now in the same size of Blake which it has tended to supersede, because overhead eccentric encourages feed and discharge, allowing higher speeds and capacity, but with higher wear and more attrition breakage and slightly lower energy efficiency. In addition as compared to an equivalent double toggle, they are cheaper and take up less floor space.

Since the jaw crusher was pioneered by Eli Whitney Blake in the 2nd quarter of the 1800s, many have twisted the Patent and come up with other types of jaw crushers in hopes of crushing rocks and stones more effectively. Those other types of jaw crusher inventors having given birth to 3 groups:

Heavy-duty crushing applications of hard-to-break, high Work Index rocks do prefer double-toggle jaw crushers as they are heavier in fabrication. A double-toggle jaw crusher outweighs the single-toggle by a factor of 2X and well as costs more in capital for the same duty. To perform its trade-off evaluation, the engineering and design firm will analyze technical factors such as:

1. Proper selection of the jaws. 2. Proper feed gradation. 3. Controlled feed rate. 4. Sufficient feeder capacity and width. 5. Adequate crusher discharge area. 6. Discharge conveyor sized to convey maximum crusher capacity.

Although the image below is of a single-toggle, it illustrates the shims used to make minor setting changes are made to the crusher by adding or removing them in the small space between the crushers mainframe and the rea toggle block.

The jaw crusher discharge opening is the distance from the valley between corrugations on one jaw to the top of the mating corrugation on the other jaw. The crusher discharge opening governs the size of finished material produced by the crusher.

Crusher must be adjusted when empty and stopped. Never close crusher discharge opening to less than minimum opening. Closing crusher opening to less than recommended will reduce the capacity of crusher and cause premature failure of shaft and bearing assembly.

To compensate for wear on toggle plate, toggle seat, pitman toggle seat, and jaws additional shims must be inserted to maintain the same crusher opening. The setting adjustment system is designed to compensate for jaw plate wear and to change the CSS (closed side setting) of the jaw crusher. The setting adjustment system is built into the back frame end.

Here also the toggle is kept in place by a compression spring. Large CSS adjustments are made to the jaw crusher by modifying the length of the toggle. Again, shims allow for minor gap adjustments as they are inserted between the mainframe and the toggle block.

is done considering the maximum rock-lump or large stone expected to be crushed and also includes the TPH tonnage rate needing to be crushed. In sizing, we not that jaw crushers will only have around 75% availability and extra sizing should permit this downtime.

As a rule, the maximum stone-lump dimension need not exceed 80% of the jaw crushers gape. For intense, a 59 x 79 machine should not see rocks larger than 80 x 59/100 = 47 or 1.2 meters across. Miners being miners, it is a certainty during day-to-day operation, the crusher will see oversized ore but is should be fine and pass-thru if no bridging takes place.

It will be seen that the pitman (226) is suspended from an eccentric on the flywheel shaft and consequently moves up and down as the latter revolves, forcing the toggle plates outwards at each revolution. The seating (234) of the rear toggle plate (239) is fixed to the crusher frame; the bottom of the swing jaw (214) is therefore pushed forward each time the pitman rises, a tension rod (245) fitted with a spring (247) being used to bring it back as the pitman falls. Thus at each revolution of the flywheel the movable jaw crushes any lump of ore once against the stationary jaw (212) allowing it to fall as it swings back on the return half-stroke until eventually the pieces have been broken small enough to drop out. It follows that the size to which the ore is crushed.

The jaw crusher is not so efficient a machine as the gyratory crusher described in the next paragraph, the chief reason for this being that its crushing action is confined to the forward stroke of the jaw only, whereas the gyratory crusher does useful work during the whole of its revolution. In addition, the jaw crusher cannot be choke-fed, as can the other machine, with the result that it is difficult to keep it working at its full capacity that is, at maximum efficiency.

Tables 5 and 6 give particulars of different sizes of jaw crushers. The capacity figures are based on ore weighing 100 lb. per cubic foot; for a heavier ore, the figures should be increased in direct proportion to its weight in pounds per cubic foot.

The JAW crusher and the GYRATORY crusher have similarities that put them into the same class of crusher. They both have the same crushing speed, 100 to 200 R.P.M. They both break the ore by compression force. And lastly, they both are able to crush the same size of ore.

In spite of their similarities, each crusher design has its own limitations and advantages that differ from the other one. A Gyratory crusher can be fed from two sides and is able to handle ore that tends to slab. Its design allows a higher-speed motor with a higher reduction ratio between the motor and the crushing surface. This means a dollar saving in energy costs.

A Jaw crusher on the other hand requires an Ely wheel to store energy. The box frame construction of this type of crusher also allows it to handle tougher ore. This design restricts the feeding of the crusher to one side only.

The ore enters from the top and the swing jaw squeezes it against the stationary jaw until it breaks. The broken ore then falls through the crusher to be taken away by a conveyor that is under the crusher.Although the jaws do the work, the real heart of this crusher is the TOGGLE PLATES, the PITMAN, and the PLY WHEEL.

These jaw crushers are ideal forsmall properties and they are of the high capacity forced feed design.On this first Forced Feed Jaw Crusher, the mainframe and bumper are cast of special alloy iron and the initial cost is low. The frame is ribbed both vertically and horizontally to give maximum strength with minimum weight. The bumper is ruggedly constructed to withstand tremendous shock loads. Steel bumper can be furnished if desired. The side bearings are bronze; the bumper bearings are of the antifriction type.

This bearing arrangement adds both strength and ease of movement. The jaw plates and cheek plates are reversible and are of the best-grade manganese steel. The jaw opening is controlled by the position of an adjustable wedge block. The crusher is usually driven by a V-to-V belt drive, but it can be arranged for either V-to-flat or fiat belt drive. The 8x10 size utilizes a split frame and maybe packed for muleback transportation. Cast steel frames can be furnished to obtain maximum durability.

This second type of forced feed rock crusher is similar in design to the Type H listed above except for having a frame and bumper made of cast steel. This steel construction makes the unit lighter per unit of size and adds considerable strength. The bearings are all of the special design; they are bronze and will stand continuous service without any danger of failure. The jaw and cheek plates are manganese steel; and are completely reversible, thus adding to their wearing life. The jaw opening is controlled by the position of an adjustable wedge block. The crushers are usually driven by V-to-V but can be arranged for V-to-flat and belt drive. The 5x6 size and the 8x10 size can be made with sectionalized frame for muleback transportation. This crusher is ideal for strenuous conditions. Consider a multi jaw crusher.

Some jaw crushers are on-floor, some aboveground, and others underground. This in many countries, and crushing many kinds of ore. The Traylor Bulldog Jaw crusher has enjoyed world wide esteem as a hard-working, profit-producing, full-proof, and trouble-free breaker since the day of its introduction, nearly twenty years ago. To be modern and get the most out of your crushing dollars, youll need the Building breaker. Wed value the privilege of telling you why by letter, through our bulletins, or in person. Write us now today -for a Blake crusher with curved jaw plates that crush finer and step up production.

When a machine has such a reputation for excellence that buyers have confidence in its ability to justify its purchase, IT MUST BE GOOD! Take the Type G Traylor Jaw Crusher, for instance. The engineers and operators of many great mining companies know from satisfying experience that this machine delivers a full measure of service and yields extra profits. So they specify it in full confidence and the purchase is made without the usual reluctance to lay out good money for a new machine.

The success of the Type G Traylor Jaw Crusheris due to several characteristics. It is (1) STRONG almost to superfluity, being built of steel throughout; it is (2) FOOL-PROOF, being provided with our patented Safety Device which prevents breakage due to tramp iron or other causes of jamming; it is (3) ECONOMICAL to operate and maintain, being fitted with our well-known patented Bulldog Pitman and Toggle System, which saves power and wear by minimizing frictionpower that is employed to deliver increased production; it is (4) CONVENIENT to transport and erect in crowded or not easily accessible locations because it is sectionalized to meet highly restrictive conditions.

Whenever mining men need a crusher that is thoroughly reliable and big producer (which is of all time) they almost invariably think first of a Traylor Type G Jaw Crusher. By experience, they know that this machine has built into it the four essentials to satisfaction and profit- strength, foolproofness, economy, and convenience.

Maximum STRENGTH lies in the liberal design and the steel of which crushers parts are made-cast steel frame, Swing Jaw, Pitman Cap and Toggles, steel Shafts and Pitman rods and manganese steel Jaw Plates and Cheek Plates. FOOLPROOFNESS is provided by our patented and time-tested safety Device which prevents breakage due to packing or tramp iron. ECONOMY is assured by our well-known Bulldog Pitman and Toggle System, which saves power and wear by minimizing friction, the power that is used to deliver greater productivity. CONVENIENCE in transportation and erection in crowded or not easily accessible locations is planned for in advance by sectionalisation to meet any restrictive conditions.

Many of the worlds greatest mining companies have standardized upon the Traylor Type G Jaw Crusher. Most of them have reordered, some of them several times. What this crusher is doing for them in the way of earning extra dollars through increased production and lowered costs, it will do for you! Investigate it closely. The more closely you do, the better youll like it.

rock crushers at kellyco | gold prospecting equipment

In order to crush rocks and extract gold, you will need the right equipment that can achieve this quickly and efficiently. That being said, utilizing rock crushers will help prevent you from missing the opportunity of hitting paydirt. Portable rock crushers will change the way you prospect for gold and with several options available, making sure that you select the correct product will be invaluable.

The term itself is pretty self-explanatory. These machines are designed to crush any type of stone from quartz to limestone and everything in between. How much is able to be processed per hour will depend on the model you purchase.

The intention of small rock crushers, such as those we have here at Kellyco, is to allow you to extract more gold instead of leaving any paydirt behind. The amount of gold that can be contained within rocks in areas you didnt know were there may surprise you. However, without a rock crusher in your arsenal, you will never be aware of what was left behind.

Portable rock crushers use a very simple approach, power. With various sized engines available depending on the model, these machines are designed to take small rocks and, thanks to a huge amount of pressure and power, crush them down and allow you to process them through your sluice box.

The aim of any small rock crusher for sale is to be able to break that rock down into a fine powder. In doing so, it will be able to pass through a classifier before going through the sluice box and any gold can then be separated. Even relatively small pieces of rock that are left intact could lead to you missing out on some gold, and when you know you have hit paydirt then you hardly want to leave anything behind.

Most models, including the Keene G-Force rock crusher, will use a hopper box with gravity to move the rocks through the crusher. The rock is fed into the hopper box and then moves into the central compartment of the crusher. A huge amount of force effectively smashes the rock at high speed and the greater the force then the finer the powder. With that in mind, the power of the engine contained within the rock crusher will be important.

With several options available, knowing which are the best rock crushers for sale will make your job of identifying the right product for you easier. Of course, budget may play a part but Kellyco does have a number of small portable rock crushers for sale across a wide price range.

There are several key points to consider when looking at purchasing a portable rock crusher. First, there is the volume of rock that can process for up to an hour. With some capable of producing over 2 tons of powder, also known as grind, this should be more than adequate for the majority of treasure hunters.

Another point to remember is the size of rock that the crusher can handle. These kinds of rock crushers for sale are not designed to take large boulders and break them down on an industrial scale. Instead, we are talking about rocks that are around one inch in size that can be effectively smashed in seconds. Once again, we recommend that you check the maximum size that the model you are looking at can take before making your purchase.

The best rock crushers for sale will contain a large hopper box, be capable of crushing a substantial amount of rock in one hour, and break things down into an easy to manage powder. As long as those points are met, then you should not have any problem extracting as much gold as possible from your expedition.

There are several additional features that deserve to be mentioned with a rock crusher. For example, you need to examine how a particular model is powered. With both gas and electric available as options, it should be easy for you to get things started. As a side-note, the gas version is often regarded as being cheaper to operate. Also, we have to think about transportation. These machines are not the lightest around which is why there are lighter models, such as the Keene trailer mounted crusher, on the market. This does make it easier to get to those more remote areas that you may wish to venture to on your expeditions.

You may wish to consider looking at the process that the rock crusher uses in order to deliver the powder. Different models may put the rock through various processes with each stage resulting in something even finer than before.

Finally, there has to be the question of replacing parts even when you are out there in the wild. Cleaning the machine and clearing it of debris is important or it may result in becoming clogged. However, models that have been manufactured by Keene will all be easy to adjust and maintain so this shouldnt be a problem.

If rock crushers are something of interest to you, but you are unsure of what to do next, then feel free to reach out to our customer service team. Contact us directly via our customer care department and our team of expert gold prospectors will be able to advise you on the best rock crusher for your needs and answer any questions that you may have.

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crushing plants for sale

As the name implies, a portable crusher or crushing plant is capable of breaking down almost type of material, organic or otherwise, from simple debris to complex ores and minerals. A concrete crusher, for example, can crush rocks and mix them with concrete and asphalt for roadside construction projects. Whether you need a used rock crusher for sale, a concrete crusher, or something for iron ore, sandstone, and other similar materials, the expert sellers at My Little Salesman have got you covered.

Choosing the right portable crusher largely depends on the type of industry youre in for example, you dont need a used stone crusher if you are going to be handling softer materials. No matter what you need to have crushed, however, there are three portable crusher types to choose from:

If you go with an impact crusher, you will have to choose between vertical and horizontal shafts. A vertical shaft impactor has a higher speed than a horizontal shaft impactor, which causes the materials to be busted into evenly-shaped cubes (which is good for handling uneven rock and ores). A horizontal shaft impactor uses hammers to do the job, and is therefore better for softer materials such as limestone and phosphate.

rock crusher - eastman rock crusher

Granite is not easy to crush to sand, main equipment has PE-7501060 jaw crusher (coarse crusher), HP300 cone crusher (fine crusher), bin, 490110 vibrating feeder, B1000x22 conveyor belt, B1000x30m conveyor belt, B800x31 conveyor belt, 4YK2460 vibrating screen, etc. contact us!

In this case, we recommend the use of a PCZ1308 heavy hammer crusher with a feed size of 930x650mm, the feed particle size is less than 600mm, the motor power is 4P 132Kw, and the processing capacity of the equipment is 100-180t/h.

Eastman is a typical direct selling enterprise with green and standardized production plants. All the delivery of the equipment will be completed within the delivery period signed by the contract to ensure the smooth commissioning of the equipment.

Rock crushers have a wide range of suitable material to choose from, whether its soft or hard, or even very hard, rock crushers can reduce those large rocks into smaller rocks, gravel, or even rock dust.Here are some typical materials that break or compress by industry crushers, such as Granite, quartz stone, river pebble, limestone, calcite, concrete, dolomite, iron ore, silicon ore, basalt and other mines, rocks and slag.

Understanding the stages of crushing process and the types of crushers that best fit each stage can simplifies your equipment selection. Each type of crusher is different and used to achieve a certain end result.

Similarly, a certain output is expected at the end of each crushing stage for the next phase of the process. Aggregate producers who pair the correct crusher to the correct stage will be the most efficient and, in turn, the most profitable.

A jaw crusher is a compression type of crusher. Material is reduced by squeezing the feed material between a moving piece of steel and a stationary piece. The discharge size is controlled by the setting or the space between those two pieces of steel. The tighter the setting, the smaller the output size and the lower the throughput capacity.

As a compression crusher, jaw crushers generally produce the coarsest material because they break the rock by the natural inherent lines of weakness. Jaw crushers are an excellent primary crusher when used to prepare rock for subsequent processing stages.

Although the chamber is round in shape, the moving piece of steel is not meant to rotate. Instead, a wedge is driven around to create compression on one side of the chamber and discharge opening on the opposite side. Cone crushers are used in secondary and tertiary roles as an alternative to impact crushers when shape is an important requirement, but the proportion of fines produced needs to be minimized.

An impact crusher uses mass and velocity to break down feed material. First, the feed material is reduced as it enters the crusher with the rotating blow bars or hammers in the rotor. The secondary breakage occurs as the material is accelerated into the stationary aprons or breaker plates.

Impact crushers tend to be used where shape is a critical requirement and the feed material is not very abrasive. The crushing action of an impact crusher breaks a rock along natural cleavage planes, giving rise to better product quality in terms of shape.

Most aggregate producers are well acquainted with the selection of crushing equipment and know it is possible to select a piece of equipment based solely on spec sheets and gradation calculations. Still, theoretical conclusions must always be weighed against practical experience regarding the material at hand and of the operational, maintenance and economical aspects of different solutions.

The duty of the primary crusher is, above all, to make it possible to transport material on a conveyor belt. In most aggregate crushing plants, primary crushing is carried out in a jaw crusher, although a gyratory primary crusher may be used. If material is easily crushed and not excessively abrasive, an impact breaker could also be the best choice.

The most important characteristics of a primary crusher are the capacity and the ability to accept raw material without blockages. A large primary crusher is more expensive to purchase than a smaller machine. For this reason, investment cost calculations for primary crushers are weighed against the costs of blasting raw material to a smaller size.

A pit-portable primary crusher can be an economically sound solution in cases where the producer is crushing at the quarry face. In modern plants, it is often advantageous to use a moveable primary crusher so it can follow the movement of the face where raw material is extracted.

The purpose of intermediate crushing is to produce various coarser fractions or to prepare material for final crushing. If the intermediate crusher is used to make railway ballast, product quality is important.

In other cases, there are normally no quality requirements, although the product must be suitable for fine crushing. In most cases, the objective is to obtain the greatest possible reduction at the lowest possible cost.

In most cases, the fine crushing and cubicization functions are combined in a single crushing stage. The selection of a crusher for tertiary crushing calls for both practical experience and theoretical know-how. This is where producers should be sure to call in an experienced applications specialist to make sure a system is properly engineered.