nordberg c series jaw crushers - metso outotec
Nordberg C Series jaw crushers have proven to be reliable and productive in thousands of mining, quarrying, recycling and industrial applications with up to 11,000 jaw crusher installations since 1975.
The core of Nordberg C Series jaw crusher is a pinned and bolted, non-welded frame construction that provides excellent fatigue strength.All the frame components are casted using an alloy developed in-house especially for jaw crushers.
A larger feed opening increases material intake and ensures that the rocks enter the jaw crushers cavity without restrictions. A steeper nip angle decreases operating costs by reducing wear on jaw dies and speeds up material flow down in the cavity.
The stroke is amplified from top to bottom, leading it being longest in the bottom of the cavity. This increases the capacity as well as the reduction ratio, resulting in high production in all kinds of operations.
The jaw crushers can be upgraded with crusher automation that enable monitoring and adjusting the settings of a feeder, crusher, and conveyor remotely. This way the crusher can be controlled from a distance making it easier and yet safer to operate.
Based on long experience and comprehensive testing at customer sites, the critical areas of jaw crushers are protected against wear. The components and parts that require renewal from time to time are engineered to be easily accessible and replaceable when needed.
Nordberg C Series jaw crushers are customizable with options for any application. Safe flywheel and drive guards protect operators from moving objects. An optional integrated motor base allows installing the crusher drive motor directly to the back of the crusher.
Get the maximum potential out of your size reduction process to achieve improved crushing performance and lower cost per ton. By using our unique simulation software, our Chamber Optimization experts can design an optimized crushing chamber that matches the exact conditions under which you operate.
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.
jaw crushers | mclanahan
Jaw Crushers are used to reduce the sizeof many different types of materials in many applications. The Jaw Crusher was first introduced by Eli Whitney Blake in 1858 as a double-toggle Jaw Crusher. Introduced in 1906, McLanahans Universal Jaw Crusher was one of the first modern era overhead eccentric Jaw Crushers. On the overhead eccentric style Jaw Crusher, the moving swing jaw is suspended on the eccentric shaft with heavy-duty double roll spherical roller bearings.
The swing jaw undergoes two types of motion: one is a swing motion toward the opposite chamber side (called a stationary jaw die due to theaction of a toggle plate), and the second is a vertical movement due to the rotation of the eccentric. These combined motions compress and push the material through the crushing chamber at a predetermined size.
More than 110 years of engineering and customer service experience keep customers running to McLanahan tomeet their production goals. McLanahan Jaw Crushers are proudly made in the USA and have imperial designs. With our grass roots design coupled with listening to customer needs for product enhancement over the years, McLanahan offers traditional hydraulic-shim adjustment Jaw Crushers as well asH-Series Jaw Crushers that featurehydraulic discharge setting adjustment, adjust-on-the-fly chamber clearing in the event the site loses power (once power is restored) and hydraulic relief for overload events with auto-reset.
Whether the traditional hydraulic-shim adjustment or the H-Series Jaw Crushers, both machines have an aggressive nip angle that providesconsistent crushing throughout the entire crushing chamber, which leads to increased production and less downtime on maintenance.
A Jaw Crusher uses compressive force for breaking material. This mechanical pressure is achieved by the crusher'stwo jaws dies, one of which is stationary and the other is movable. These two vertical manganese jaw dies create a V-shaped cavity called the crushing chamber, where the top of the crushing chamber is larger than the bottom. Jaw Crushers are sized by the top opening of the crushing chamber. For example, a 32 x 54 Jaw Crusher measures 32" from jaw die to jaw dieat the top opening or gape opening and54 across the width of the two jaw dies.
The narrower bottom opening of the crushing chamber is used to size the discharge material. A toggle plate and tension rods hold the pitman tight near the bottom of the moving swing jaw. The toggle plate is designed to perform like a fuse and protect the crusher in the event that an uncrushable materialenters the crushing chamber. As a rule, Jaw Crushers have a 6:1 or 8:1 ratio for crushing material. Still using the 32 x 54 Jaw Crusher example, the top size of thefeed entering the crushing chamber has to follow the F80 rule that 80% of the top size feed material is smaller than the gape opening. Using the F80 rule with the 32 x 54 Jaw Crusher, the32 gape opening equals a26 top sized feed, and with the 6:1 ratio of reduction, the discharge setting would be around 4.
Since the crushing of the material is not performed in one stroke of the eccentric shaft, massive weighted flywheels are attached to the eccentric shaft andpowered by a motor. The flywheels transfer the inertia required to crush thematerial until it passes the discharge opening.
While Jaw Crushers are mostly used as the first stage of material reduction in systems that may use several crushers to complete the circuit, the Jaw Crusher has also been used as a second-stage crushing unit. Depending on the application requirements, Jaw Crushers can be used in stationary, wheeled portable and track-mounted locations. The Jaw Crusher is well suited for a variety of applications, including rock quarries, sand and gravel, mining, construction and demolitionrecycling, construction aggregates, road and railway construction, metallurgy, water conservancy and chemical industry.
F100 is the maximum gape opening on a Jaw Crusher. F80 is the feed size to the Jaw Crusher, calculated by taking 80 times the gape opening divided by 100. P80 is the percent passing the closed side setting in tph.
A best practice, if possible, is to blend the material arriving from the source. This will ensure a constant and well-graded feed to the crushing chamber. In turn, this will produce a steady rate of tph andpromote inter-particle crushing that helps break any flat or elongated material. It also aids in equal work hardening the manganese jaw dies and prolonging the life of the jaw dies.
Usually a Jaw Crusher is in an open circuit, but it can be used in a close circuit if the return load is not greater than 20% of the total feed and the raw feed is free of fines smaller than the closed side setting.
Efficiency can be defined by the ratio of the work done by a machine to the energy supplied to it. To apply what this means to your crusher, in your reduction process you are producing exactly the sizes your market is demanding. In the past, quarries produced a range of single-size aggregate products up to 40 mm in size. However, the trend for highly specified aggregate has meant that products have become increasingly finer. Currently, many quarries do not produce significant quantities of aggregate coarser than 20 mm; it is not unusual for material coarser than 10 mm to be stockpiled for further crushing.
jaw crushers for sale
The jaw crushers we offer for sale include Superior, Type B Blake, Fine-Reduction, and Dodge sizes, 4 by 6 to 84 by 66 inches. A reciprocating machine, the crushes material in a straight line between jaws without grinding or rubbing surfaces.
As you compare this jaw crusher feature for feature with other makes youll see how this modern crusher lowers principal costspower consumption; lubrication; jaw plate, toggle plate, and bearing wear youll understand why we say the crusher promises you a new low cost per ton of material crushed!
Firstthose who have rock or ore tougher and more abrasive than most material. Secondthe operators whove had difficulty with other designs of crushers. And finallythe operators who naturally buy the bestexpecting their added investment to be written off in comparatively short time through lower operating and maintenance costs!
Compare the dimensions with those of conventional jaw crushers. It measures up to 20% longer; has up to 35% deeper crushing chamber! And while you naturally expect to pay more for this bigger,deluxe crusher, it follows that you get more too! For example:
You get a crushing chamber with a full-width receiving opening increased capacity! You get an acute crushing chamber that minimizes slippage very important with hard, tough materials. You cut down crushing power required through longer pitman and front toggle. You reduce packing, get closer setting through the longer jaw, non-choking plates. You lower maintenance cost, get longer jaw plate, toggle, and bearing life through lower structural stresses, simplified design.
Frames of these crushers are built for maximum rigidity designed to prevent distortion during operation. Side members are heavy steel plate, reinforced by steel ribbing. End members are cast steel, of box section design, to provide maximum strength.
The side frames are deep-welded and then stress-relieved in thehuge annealing furnaces to eliminate possible failure adjacent to welds. The result is a uniformly strong frame that will remain true during the long service life of the crusher.
A jaw crusher frames are of sectionalized construction to facilitate handling. This design minimizes heavy lifts makes the crusher suitable for installations where parts must be passed down a shaft or through a tunnel. End members are attached between side members with vertical tongue and groove joints and held together with fitted bolts. Long-bearing surfaces prevent angular distortion.
Important differences in design show up visually when a cross-section of the crushing chamber of a conventional crusher is superimposed over that of the crusher. Now you can see the advantages of the 1 /3 deeper chamber using non-choking jaw plates. Its more acute crushing angle is carried to the very top of the chamberpermits nipping the largest material that can enter the receiving opening!
Lower plates on the swing and stationary jaws are suspended from projections on jaws. These plates also support the upper plates. This exclusive feature permits the free expansion of manganese steel jaw plates greatly minimizes the possibility of buckling or warping prevents costly shutdowns!
SWING AND STATIONARY JAWS on the jaw crusher are annealed cast steel box section construction designed for maximum rigidity. The jaw swings on a sturdy shaft that is clamped to the crusher frame. This shaft also serves as a reinforcing tie across the top of the frame. The entire design facilitates lubrication and replacement of shaft bearings.
Jaw plates are constructed of manganese steel and have corrugated crushing surfaces which reduce the power required for fracturing material. The jaw plates are built into two pieces to jaw. Those on the swing jaw are interchangeable. Plates on the stationary jaw are the non-choking type, not interchangeable. Lower plates on both jaws are suspended from jaw projections and support upper plates. The main advantage of this construction (see above) is to permit the free flow of manganese steel. All four plates are held in place by large through-bolts equipped with springs to prevent bolt breakage.
Heres still another feature youll find on the jaw crusher! Renewable wearing plates between the cast manganese steel jaw plates and swing and stationary jaws provide a firm backing for the jaw plates. If, for any reason, looseness develops in the jaw plates, these wearing plates, not the jaws, take the wear! By protecting expensive jaw castings, these wearing plates increase crusher life simplify maintenance minimize causes for shutdowns.
The heavy, two-piece corrugated manganese steel jaw plate is designed to fracture the toughest kinds of rock or ore with a minimum of power. The unobstructed clearances above, between, and below the plate sections permit free flow of manganese steel.
This construction eliminates the need for extra holding pieces, greatly minimizes the shearing of bolts. The amply designed shaft not only supports the swing jaw but reinforces the frame, serving as a tie between sides.
Notice the extra length of this jaw as compared to conventional types. Designed up to one-third longer, it exerts greater pressures in the upper portion of the crushing chamber, distributes crushing action more evenly. The result is a gradual reduction of ore to the choking point, and increased capacity!
Another, southern iron ore mining company, chose this 48 by 42-inch crusher to replace a conventional design that had failed. They explained, In our process, weve got to have a ruggedly designed crusher capable of continuous operation!
CRUSHERSin sizes from 36 by 25 to 60 by 48 inchesare giving these and other operators more for their money more capacity; more crusher life; more satisfaction! It can pay you too, to know more about this great crusher! Why not call in your use today!
All sizes of crushers feature a three-piece toggle plate construction. Worn ends may be replaced no need to discard the entire toggle. Bronze toggle ends fit into replaceable hardened steel toggle seats in swing jaw. Properly lubricated, this assembly materially reduces maintenance.
Toggle plates for these jaw crushers are of three-piece construction, consisting of an iron center section (2) to which are bolted two replaceable bronze ends (1 and 3). Toggle seats are carefully machined and equipped with protecting shields that deflect dust and dirt.
A toggle block, arranged for both vertical and horizontal adjustment, is provided at the rear of the frame. By inserting shims above the toggle block, the crushing stroke can be adjusted. Insertion of shims behind the toggle block adjusts the size of the discharge opening. Parallel alignment is assured and unnecessary strain in the crushing machine is avoided.
The pitman in any jaw crusher is essentially a tension member. However, because it also has a vertical reciprocating movement, it is desirable to keep its weight as low as possible, consistent with maintaining the required strength.
In the crusher this is accomplished by designing the pitman as a skeleton member, first to provide the necessary strength for tension and with stiffness against overturning thrust provided for by deep integral webs.
The pitman is designed with only four large-cap bolts, and the pitman cap is ribbed for proper distribution of the load to these bolts. The pitman is swung on the eccentric shaft which is supported by removable, water-cooled bearings on the frame.
The pitman is a two-piece annealed cast steel construction, with a cap designed for water cooling. Bearing surfaces on both pitman and cap are babbitted and are joined together by four large forged steel bolts. The elimination of excess bolts inherently found in conventional design results in a more uniform distribution of load.
The pitman (eccentric) shaft is heat-treated, forged steel constructionof ample diameter so that stress, even under the shock of suddenly clogged jaws, is low. The shaft is carried in removable, water-cooled, babbitted bearings designed to permit quick removal or replacement without having to strip the crusher.
Heres a typical toggle plate for jaw crushers. It is constructed in three pieceswith the center section of iron, two ends of bronze, designed for quick bolting to the center section. This unique construction materially reduces replacement and maintenance costs makes it unnecessary to discard toggles when ends alone are worn!
A critical point in the operation of large jaw crushers is the arrangement of the swing jaw and its supporting shaft. While in most crushers the jaw is pressed on the shaft and the latter swings in frame, in the jaw crusher the opposite principle is usedshaft is clamped in frame and jaw swings on the shaft!
Another point has been lubrication. In operation, the actual movement of the swing jaw is relatively small. The result is difficulty in proper lubrication of bearing surfaces. The crusher uses a special means of lubrication and in addition is designed with the new replaceable, graphite-impregnated Scor-proof bushings which greatly reduce wear on the expensive shaftssince these bushings, and not the shaft, now take the wear!
Very careful attention is required in the lubrication of heavy mechanical units like the jaw crusher. A thorough study made of existing types of lubrication systems resulted in the selection of a pair of systems that assure positive delivery of lubricant to point of maximum pressure.
The 48 by 42-inch jaw crusher and smaller sizes are force-fed by an automatic high-pressure lubricator to the swing jaw, pitman, and main bearings as illustrated in Figure 1. A motor-driven pump forces the lubricant through pressure buildup cylinders and out to distributors which dispense a precise amount to each of the points on the bearings. No oil return is provided.
The 60 by 48-inch jaw crusher and larger sizes are lubricated by a closed circuit oiling system to the pitman and main bearings, as illustrated by the solid lines in Figure 2, and by high-pressure lubrication fittings connected to the swing jaw bearings, as illustrated by the dotted lines in Figure 2. A motor-driven gear pump forces the oil through pressure-type filters and a condenser-type cooler to a distribution manifold mounted on the crusher. The oil flows through the bearings, lubricating and cooling, and back to the reservoir for recirculation. The swing jaw bearings require servicing by portable grease equipment.
The capacity of the jaw crusher is greater than that of conventional jaw crushers. One reason is its uniform-wear crushing chamber with full-width receiving opening. Another reasonits a more acute crushing angle.
Slippage is reduced packing and choking are prevented by a more even distribution of crushing action throughout the entire length of the crushing chamber. The result is a gradual reduction of material to the choking point increased capacity!
Capacities given below are approximate and are based on standard speeds, jaw motions, and jaw plates, with a feed of quarry or mine run material weighing 100 lb per cu ft crushed. Most stone and low-grade ores are considered weighing 100 lb per cu ft crushed.
The table is based on continuous feeding. Reserve for normal interruption of feeding should be provided. A heavy-duty apron feeder is recommended for most installations, particularly where large cars or trucks are used in the quarry or mine.
When feed to crushers is scalped over grizzlies or screens the number of rejections, or material that will have to be crushed should be determined in establishing the tonnage to be handled by the crusher. The number of fines received from mine or quarry will vary widely depending on each application and should be taken into consideration in determining the overall capacity.
Whatever equipment you operate, you can be certain of careful, considerate handling of orders for repair or replacement parts. In most cases parts are shipped directly from stockyoure assured of fast delivery. The view at left shows a small portion of crushing, cement, and mining equipment parts normally carries.
Repair parts temporarily depleted or not carried in stock will be furnished in time to meet requirements whenever possible. Anticipation of future needs, placing orders in advance, will greatly aid in avoiding unforeseen delays. Genuine parts are exact duplicates or improvements of original components of your machinery, not makeshift substitutes.