purchase cost of a vibrating screen

how to use a flash pass at six flags: 12 steps (with pictures)

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Using a Flash Pass at Six Flags is a convenient way to enjoy more rides during a trip to the amusement park. A Flash Pass usually comes in the form of a Q-Bot that you are supposed to make reservations on and keep with you as you enjoy the park. The cost of a Flash Pass is more than the regular admission, but park-goers who use the pass typically ride more attractions and wait in line for less time.

To use a Flash Pass at Six Flags, you'll need to buy it at the entrance, or book it online and collect it when you arrive. Your Flash Pass will come in the form of a Q-Bot, which is a small beeper that lets you reserve rides. Check online to see which rides your Flash Pass works for, although it usually covers all the major rides in the park. To make reservations, scan your Q-Bot on the scanning station in front of each ride, or do it directly from your Q-Bot. When your Q-Bot vibrates to notify you of your reservation, head to the Flash Pass entrance for the ride you booked. At the end of the day, make sure you return your Q-Bot so you dont get charged a fee. For more tips, including how to cancel a ride reservation using your Six Flags flash pass, read on! Did this summary help you?YesNo

flex-mat vibrating wire screens

FLEX-MAT vibrating wire screens will provide more spec product at a lower operating cost, while delivering more wear life and eliminating blinding, pegging and clogging issues.

When using static screening media (woven cloth, polyurethane or rubber panels, etc.), the only vibration is induced by the screen box which typically vibrates with a range of 500-1,000 strokes per minute. FLEX-MAT high-vibration wire screens have individual wires that vibrate independently at a high-frequency of between 6,000-10,000 strokes per minutes.

MAJOR ensures optimum wire quality and consistency at all times by developing, (through its own specifications and internal laboratory quality controls), the best recipe for a wires chemical content to optimize all factors, and by using the most advanced patented wire-making process, MAJOR also only uses the highest quality of stainless steel wires with the highest tensile strength, available in Type 304 and Type 316.

This process is the ultimate way of improving the molecular structure. The rod is heated first and then cooled at a controlled temperature to optimize the molecular structure before being drawn through a conic die.

Open area varies with the screening media type and affects the tonnage or volume of material that can be processed on a screen deck. On screen boxes with multiple decks, the relation of open area and material gradation between the decks is an important efficiency factor that needs to be balanced.

Its flat surface offers 100% of surface wear, compared to only the upper knuckles of woven screens, which results in the even wear of its wire, maintaining the opening within the given specification for a longer time. Polyurethane panels however, lose opening specification after a certain percentage of wear due to the slight V shape of the opening.

Designed to provide high-performance on all decks for a wide range of materials, FLEX-MAT screens provides the highest-efficiency level of self-cleaning capacity for higher throughput, reduced downtime as well as maintenance and replacement costs.

porta sifter screener - midwestern industries, inc

The Porta-Sifter is an inexpensive, versatile, go-anywhere vibrating screener, perfect for research, batch runs, or continuous production. Its simplistic design and few moving parts require minimal maintenance while providing top screening performance.

The vibrating action can be generated wherever electrical or pneumatic connections are available. The electric model is available with a 110-volt single phase or a 230/460-volt three-phase motor. Variable amplitude on the air model allows selection of the most efficient vibrating screening action for different meshes and materials.

Routine or continuous screening operations can benefit from the various mounting options. A rollaway stand allows for easy transitioning between different screening applications without the added expense of multiple screening units. In addition, the Porta-Sifter may be mounted using a swing-away wall mounting system or over an opening (on any level surface), without expensive measures for vibration control.

Midwesterns commitment to providing our customers with outstanding screening products continues with our full line of replacement round screens. Our screens are manufactured to fit all makes and models of round vibratory screeners.

vibrating screen working principle

When the smaller rock has to be classified a vibrating screen will be used.The simplest Vibrating Screen Working Principle can be explained using the single deck screen and put it onto an inclined frame. The frame is mounted on springs. The vibration is generated from an unbalanced flywheel. A very erratic motion is developed when this wheel is rotated. You will find these simple screens in smaller operations and rock quarries where sizing isnt as critical. As the performance of this type of screen isnt good enough to meet the requirements of most mining operations two variations of this screen have been developed.

In the majority of cases, the types of screen decks that you will be operating will be either the horizontal screen or the inclined vibrating screen. The names of these screens do not reflect the angle that the screens are on, they reflect the direction of the motion that is creating the vibration.

An eccentric shaft is used in the inclined vibrating screen. There is an advantage of using this method of vibration generation over the unbalanced flywheel method first mentioned. The vibration of an unbalanced flywheel is very violent. This causes mechanical failure and structural damage to occur. The four-bearing system greatly reduces this problem. Why these screens are vibrated is to ensure that the ore comes into contact will the screen. By vibrating the screen the rock will be bounced around on top of it. This means, that by the time that the rock has traveled the length of the screen, it will have had the opportunity of hitting the screen mesh at just the right angle to be able to penetrate through it. If the rock is small enough it will be removed from the circuit. The large rock will, of course, be taken to the next stage in the process. Depending upon the tonnage and the size of the feed, there may be two sets of screens for each machine.

The reason for using two decks is to increase the surface area that the ore has to come into contact with. The top deck will have bigger holes in the grid of the screen. The size of the ore that it will be removed will be larger than that on the bottom. Only the small rock that is able to pass through the bottom screen will be removed from the circuit. In most cases the large rock that was on top of each screen will be mixed back together again.

The main cause of mechanical failure in screen decks is vibration. Even the frame, body, and bearings are affected by this. The larger the screen the bigger the effect. The vibration will crystallize the molecular structure of the metal causing what is known as METAL FATIGUE to develop. The first sign that an operator has indicated that the fatigue in the body of the screen deck is almost at a critical stage in its development are the hairline cracks that will appear around the vibrations point of origin. The bearings on the bigger screens have to be watched closer than most as they tend to fail suddenly. This is due to the vibration as well.

In plant design, it is usual to install a screen ahead of the secondary crusher to bypass any ore which has already been crushed small enough, and so to relieve it of unnecessary work. Very close screening is not required and some sort of moving bar or ring grizzly can well be used, but the modern method is to employ for the purpose a heavy-duty vibrating screen of the Hummer type which has no external moving parts to wear out ; the vibrator is totally enclosed and the only part subjected to wear is the surface of the screen.

The Hummer Screen, illustrated in Fig. 6, is the machine usually employed for the work, being designed for heavy and rough duty. It consists of a fixed frame, set on the slope, across which is tightly stretched a woven-wire screen composed of large diameter wires, or rods, of a special, hard-wearing alloy. A metal strip, bent over to the required angle, is fitted along the length of each side of the screen so that it can be secured to the frame at the correct tension by means of spring-loaded hook bolts. A vibrating mechanism attached to the middle of the screen imparts rapid vibrations of small amplitude to its surface, making the ore, which enters at the top, pass down it in an even mobile stream. The spring-loaded bolts, which can be seen in section in Fig. 7, movewith a hinge action, allowing unrestricted movement of the entire screening surface without transmitting the vibrations to the frame.

One, two, or three vibrators, depending on the length of the screen, are mounted across the frame and are connected through their armatures with a steel strip securely fixed down the middle of the screen. The powerful Type 50 Vibrator, used for heavy work, is shown in Fig. 7. The movement of the armature is directly controlled by the solenoid coil, which is connected by an external cable with a supply of 15-cycle single-phase alternating current ; this produces the alternating field in the coil that causes the up-and-down movement of the armature at the rate of thirty vibrations per second. At the end of every return stroke it hits a striking block and imparts to the screen a jerk which throws the larger pieces of ore to the top of the bed and gives the fine particles a better chance of passing through the meshes during the rest of the cycle. The motion can be regulated by spiral springs controlled by a handwheel, thus enabling the intensity of the vibrations to be adjusted within close limits. No lubrication is required either for the vibrating mechanism or for any other part of the screen, and the 15-cycle alternating current is usually supplied by a special motor-generator set placed somewhere where dust cannot reach it.

The Type 70 Screen is usually made 4 ft. wide and from 5 to 10 ft. in length. For the rough work described above it can be relied upon to give a capacity of 4 to 5 tons per square foot when screening to about in. and set at a slope of 25 to 30 degrees to the horizontal. The Type 50 Vibrator requires about 2 h.p. for its operation.

The determination of screen capacity is a very complex subject. There is a lot of theory on the subject that has been developed over many years of the manufacture of screens and much study of the results of their use. However, it is still necessary to test the results of a new installation to be reasonably certain of the screen capacity.

A general rule of thumb for good screening is that: The bed depth of material at the discharge end of a screen should never be over four times the size opening in the screen surface for material weighing 100 pounds per cubic foot or three times for material weighing 50 pounds per cubic foot. The feed end depth can be greater, particularly if the feed contains a large percentage of fines. Other interrelated factors are:

Vibration is produced on inclined screens by circular motion in a plane perpendicular to the screen with one-eighth to -in. amplitude at 700-1000 cycles per minute. The vibration lifts the material producing stratification. And with the screen on an incline, the material will cascade down the slope, introducing the probability that the particles will either pass through the screen openings or over their surface.

Screen capacity is dependent on the type, available area, and cleanliness of the screen and screenability of the aggregate. Belowis a general guide for determining screen capacity. The values may be used for dried aggregate where blinding (plugged screen openings), moisture build-up or other screening problems will not be encountered. In this table it is assumed that approximately 25% of the screen load is retained, for example, if the capacity of a screen is 100 tons/hr (tph) the approximate load on the screen would be 133 tph.

It is possible to not have enough material on a screen for it to be effective. For very small feed rates, the efficiency of a screen increases with increasing tonnage on the screen. The bed of oversize material on top of the marginal particlesstratification prevents them from bouncing around excessively, increases their number of attempts to get through the screen, and helps push them through. However, beyond an optimum point increasing tonnage on the screen causes a rather rapid decrease in the efficiency of the screen to serve its purpose.

Two common methods for calculating screen efficiency depend on whether the desired product is overs or throughs from the screen deck. If the oversize is considered to be the product, the screen operation should remove as much as possible of the undersize material. In that case, screen performance is based on the efficiency of undersize removal. When the throughs are considered to be the product, the operation should recover as much of the undersize material as possible. In that case, screen performance is based on the efficiency of undersize recovery.

These efficiency determinations necessitate taking a sample of the feed to the screen deck and one of the material that passes over the deck, that is, does not pass through it. These samples are subjected to sieve analysis tests to find the gradation of the materials. The results of these tests lead to the efficiencies. The equations for the screen efficiencies are as follows:

In both cases the amount of undersize material, which is included in the material that goes over the screen is relatively small. In Case 1 the undersize going over the screen is 19 10 = 9 tph, whereas in Case 2 the undersize going over is 55 50 = 5 tph. That would suggest that the efficiency of the screen in removing undersize material is nearly the same. However, it is the proportion of undersize material that is in the material going over the screen, that is, not passed through the screen, that determines the efficiency of the screen.

In the first cases the product is the oversize material fed to the screen and passed over it. And screen efficiency is based on how well the undersize material is removed from the overs. In other cases the undersize material fed to the screen, that is, the throughs, is considered the product. And the efficiency is dependent on how much of the undersize material is recovered in the throughs. This screen efficiency is determined by the Equation B above.An example using the case 1 situation for the throughs as the product gives a new case to consider for screen efficiency.

Generally, manufacturers of screening units of one, two, or three decks specify the many dimensions that may be of concern to the user, including the total headroom required for screen angles of 10-25 from the horizontal. Very few manufacturers show in their screen specifications the capacity to expect in tph per square foot of screen area. If they do indicate capacities for different screen openings, the bases are that the feed be granular free-flowing material with a unit weight of 100 lb/cu ft. Also the screen cloth will have 50% or more open area, 25% of total feed passing over the deck, 40% is half size, and screen efficiency is 90%. And all of those stipulations are for a one-deck unit with the deck at an 18 to 20 slope.

As was discussed with screen efficiencies, there will be some overs on the first passes that will contain undersize material but will not go through the screen. This material will continue recirculating until it passes through the screen. This is called the circulating load. By definition, circulating load equals the total feed to the crusher system with screens minus the new feed to the crusher. It is stated as a percentage of the new feed to the crusher. The equation for circulating load percentage is:

To help understand this determination and the equation use, take the example of 200 tph original or new material to the crusher. Assume 100% screen efficiency and 30% oversize in the crusher input. For the successive cycles of the circulating load:

The values for the circulating load percentages can be tabulated for various typical screen efficiencies and percents of oversize in the crusher product from one to 99%. This will expedite the determination for the circulating load in a closed Circuit crusher and screening system.

Among the key factors that have to be taken into account in determining the screen area required is the deck correction. A top deck should have a capacity as determined by trial and testing of the product output, but the capacity of each succeeding lower deck will be reduced by 10% because of the lower amount of oversize for stratification on the following decks. For example, the third deck would be 80% as effective as the top deck. Wash water or spray will increase the effectiveness of the screens with openings of less than 1 in. in size. In fact, a deck with water spray on 3/16 in. openings will be more than three times as effective as the same size without the water spray.

For efficient wet or dry screeningHi-capacity, 2-bearing design. Flywheel weights counterbalance eccentric shaft giving a true-circle motion to screen. Spring suspensions carry the weight. Bearings support only weight of shaft. Screen is free to float and follow positive screening motion without power-consuming friction losses. Saves up to 50% HP over4- bearing types. Sizes 1 x 2 to 6 x 14, single or double deck types, suspended or floor mounted units.Also Revolving (Trommel) Screens. For sizing, desliming or scrubbing. Sizes from 30 x 60 to 120.

TheVibrating Screen has rapidly come to the front as a leader in the sizing and dewatering of mining and industrial products. Its almost unlimited uses vary from the screening for size of crusher products to the accurate sizing of medicinal pellets. The Vibrating Screen is also used for wet sizing by operating the screen on an uphill slope, the lower end being under the surface of the liquid.

The main feature of the Vibrating Screen is the patented mechanism. In operation, the screen shaft rotates on two eccentrically mounted bearings, and this eccentric motion is transmitted into the screen body, causing a true circular throw motion, the radius of which is equivalent to the radius of eccentricity on the eccentric portion of the shaft. The simplicity of this construction allows the screen to be manufactured with a light weight but sturdy mechanism which is low in initial cost, low in maintenance and power costs, and yet has a high, positive capacity.

The Vibrating Screen is available in single and multiple deck units for floor mounting or suspension. The side panels are equipped with flanges containing precision punched bolt holes so that an additional deck may be added in the future by merely bolting the new deck either on the top or the bottom of the original deck. The advantage of this feature is that added capacity is gained without purchasing a separate mechanism, since the mechanisms originally furnished are designed for this feature. A positivemethod of maintaining proper screen tension is employed, the method depending on the wire diameter involved. Screen cloths are mounted on rubber covered camber bars, slightly arched for even distribution.

Standard screens are furnished with suspension rod or cable assemblies, or floor mounting brackets. Initial covering of standard steel screen cloth is included for separations down to 20 mesh. Suspension frame, fine mesh wire, and dust enclosure are furnished at a slight additional cost. Motor driven units include totally-enclosed, ball-bearing motors. The Vibrating Screen can be driven from either side. The driven sheave is included on units furnished without the drive.

The following table shows the many sizes available. Standard screens listed below are available in single and double deck units. The triple and quadruple deck units consist of double deck units with an additional deck or decks flanged to the original deck. Please consult our experienced staff of screening engineers for additional information and recommendations on your screening problems.

An extremely simple, positive method of imparting uniform vibration to the screen body. Using only two bearings and with no dead weight supported by them, the shaft is in effect floating on the two heavy-duty bearings.

The unit consists of the freely suspended screen body and a shaft assembly carried by the screen body. Near each end of the shaft, an eccentric portion is turned. The shaft is counterbalanced, by weighted fly-wheels, against the weight of the screen and loads that may be superimposed on it. When the shaft rotates, eccentric motion is transmitted from the eccentric portions, through the two bearings, to the screen frame.

The patented design of Dillon Vibrating Screens requires just two bearings instead of the four used in ordinary mechanical screens, resulting in simplicity of construction which cuts power cost in half for any screening job; reduces operating and maintenance costs.

With this simplified, lighter weight construction all power is put to useful work thus, the screen can operate at higher speeds when desired, giving greater screening capacity at lower power cost. The sting of the positive, high speed vibration eliminates blinding of screen openings.

The sketches below demonstrate the four standard methods of fastening a screen cloth to the Dillon Screen. The choice of method is generally dependent on screen wire diameters. It is recommended that the following guide be followed:

Before Separation can take place we need to get the fine particles to the bottom of the pile next to the screen deck openings and the coarse particles to the top. Without this phenomenon, we would have all the big particles blocking the openings with the fines resting atop of them and never going through.

We need to state that 100% efficiency, that is, putting every undersize particle through and every oversize particle over, is impossible. If you put 95% of the undersize pieces through we in the screen business call that commercially perfect.

optimised vibrating screens boost family business - quarry

A third-generation family quarrying business is maintaining its commitment to quality across changing seasons through its decades-long preference for sophisticated and optimised vibrating screens and their screen media.

The Peace River region of northeastern British Columbia, in Canada, is often associated with rich soils and moderate temperatures, making it an ideal agricultural environment. But there is also plenty of income to be made just below the surface. An aggregates producer recognised this in the mid-1960s and decided to take action.

In 1966, Nels Ostero established a sand and gravel operation in the Peace River Region Nels Ostero Ltd. Since then, the company has grown significantly but has always remained humble and family-orientated. Nels Osteros son Tom Ostero took over the plant in 1982, and in 2007, his grandson Nilson Ostero assumed the manager position where he remains today.

The plant, which resides on 130 hectares of land, supplies sand and gravel for residential and commercial needs in the Peace River regional district. The companys products are used in concrete applications, asphalt plants, oil fields and highways. With a capacity of more than one million tonnes per year, the equipment on-site plays a huge role in the plants success.

To keep up with the demand of sand and gravel products, the quarry requires top level machinery. There are 11 vibrating screens, two crushers and dozens of loaders, trucks and excavators on-site, all of which need to be performing efficiently.

Haver & Boecker Niagara has been delivering dependable equipment to Nels Ostero for decades. In fact, the Canadian-based screen manufacturer has been Nels Osteros go-to since the quarrys first years of establishment, back when the manufacturer was known asWSTyler.

The first piece of Haver & Boecker Niagara equipment the company purchased was a Ty-Rock (today known as an F-class vibrating screen) installed in 1966. Since then, they have added a number of technologies from themanufacturer.

My father chose the company because of the reliability of the equipment, Nilson Ostero said. I have tried some different equipment and screen media brands over the years, but nothing compares to Haver & Boecker Niagara.

Most recently, Nilson Ostero replaced his two 4.8m x 2.1m machines, which were situated at the finishing end of the operation. They were supplied by another manufacturer and had been running since the 1980s. The equipment was outdated, inefficient and required more maintenance than the value they offered. He turned to Haver & Boecker Niagara which evaluated his operation and recommended implementing two Niagara T-class machines. The new screens have proven themselves a good fit, increasing capacity and requiring little to no maintenance.

The T-class machines are on their third season with us, and we havent had a single issue, Nilson Ostero said. They allow us 20 per cent more capacity than our old screens, but more importantly they are stronger andmore reliable.

Haver & Boecker Niagara characterises the T-class machines as highly efficient and durable, which is important to the success of any screening business. This is especially true for this particular operation, which runs year-round and sees the effects of cold weather on material and screening equipment.

The British Columbia winter weather averages about four degrees Celsius but can dip down as low as -40oC. While some screen plants shut down their whole operation in the winter, Nilson Osteros high performing equipment allows him to performcrushing and screening year-round. When temperatures remain steadily below -3o C, they pause aggregate washing. However, even with a portion of the operations process shut down, they are still able to produce more than an operation that has to completely shut down for several months.

The colder it gets outside, the stickier the material becomes, Nilson Ostero said. The extra moisture can lead to blinding and pegging, resulting in downtime for maintenance to clear out the material. That doesnt happen with the T-class machines.

At the end of the day, if the guys are working with good equipment, they are happier and perform better, Nilson Ostero said. Safety is obviously a big deal, but another thing is providing efficient, top-notch machines that dont require unnecessary maintenance.

Maintenance is required on all jobsites, but unexpected maintenance and subsequent shutdowns can equate to a significant loss of money for any company. Scheduled maintenance activities are only possible with thorough analysis and planning as well as quality equipment and screen media. Nilson Ostero consistently found that any attempt to cut corners only resulted in lost profits. Each time he experimented with lower-cost screen media, he would watch as unexpected downtime and lost revenue skyrocketed.

Until the operation implemented the Haver & Boecker PROdeck method, the standard screen media required attention after every eight shifts, and a complete change-out every two weeks. PROdeck evaluates the screening process to effectively blend screen media for the highest production with the least amount of unscheduled downtime. Markus Kopper, general manager of Haver & Boecker Niagara Rocky Mountains, and Dave Warden, Haver & Boecker Niagara sales manager, worked with the company to determine the optimal screen media combination for the operation. This included a combination of Ty-Max, Ty-Wire and traditional woven wire, as well as Majors Flex-Mat.

Haver & Boecker Niagara partners with each customer and thoroughly evaluates an operation before making recommendations, Kopper said. For Nels Ostero, they were able to achieve a 70 per deck increase in wear life with our PROdeck approach.

Nilson Ostero also consulted with Haver & Boecker Niagara to determine if any additional upgrades for his vibrating screens could reduce the time required for maintenance and screen change-outs. Hefound a time saver in the companys Ty-Rail quick-tensioning system. The new T-class machines are equipped with this system, which combines the tension rail and all hardware together in one assembly. Ty-Rail has simplified the process and saves his team at least three hours each time a change-out is needed, as well as helping to eliminate losing nuts and bolts into the hoppers below.

A complete screen change-out, on one screen, would have normally taken us five or six hours, Ostero said. But with Ty-Rail, we can do it in as few as three hours. And guys arent dropping bolts every 15 seconds, so thats anadded bonus.

The three-hour time savings, coupled with increased throughput, resulted in an overall production increase over the first year. On top of that, it saved an estimated eight to 10 days of downtime per season, which equates to an increase of thousands of dollars.

However, Ty-Rail wasnt the only time-saving option Nilson Ostero discovered. After years of frequently replacing worn out cross-beams, he opted to add Zip-Guard to his T-class machines. The 13mm-thick polyurethane liner is designed to reduce the impact of passing material by protecting the cross beams from wear. This results in increased equipment longevity and minimised downtime formaintenance.

All of the technologies on-site are supported by an ongoing service program, which gives Nels Ostero an added level of confidence in the products. Haver & Boecker Niagara begins every service visit with its signature Pulse vibration analysis. The advanced vibration analysis technology is designed to help customers, like Nilson Ostero, examine the health of their vibrating screen. Haver & Boecker Niagara technicians use the technology and analysis to help detect irregularities that could translate into diminished performance, decreased efficiency, increased operating costs and imminent breakdowns.

Markus and his team used Pulse to help me spot issues that our team wouldnt have normally been able to find, Nilson Ostero said. Haver & Boecker Niagara first ran it on my machines right after they installed them, and now they run it once a year. It has caught problems that may have cost me money down the road, including a twisted frame on one of my screens. We knew there was a problem with the unit, but with Pulse, Haver & Boecker Niagarasservice technician determined exactlywhat was wrong.

Since the companys inception, Nels Ostero has grown to become one of the largest sand and gravel producers in the area employing more than 30 people, several of whom have been with the company for more than 15 years. With a constant focus on relationships and quality, the Ostero family built a longstanding business on enduring whatever the economy throws at them, all while maintaining their reputation for consistently providing quality product that meets the demands of theircustomers.

Looking toward the future, Nilson Ostero hopes to continue to grow the business by increasing output year over year, continue retaining and adding employees, and perhaps most importantly keep the businessin the family and one day pass it on to his children tocontinue the family tradition.

ebay

When concrete is poured into forms to make a horizontal surface, air bubbles and excess water may be trapped inside. Vibration is used to remove the bubbles and water to ensure a smooth, flat surface once the concrete dries. Screeds are a commonly used type of concrete vibrator.

There are basically four categories of concrete vibrators with specific applications: Internal, Form, Surface, and Tables. Screeds are in the Surface category. They can smooth surfaces for depths of concrete up to twenty centimeters and are utilized for long, horizontal surfaces of concrete poured into forms, such as sidewalks and other types of pavement.

Because of their speed relative to other types, screed vibrators are the preferred type for larger job sites. For depths of concrete greater than twenty centimeters, screeds can be used in conjunction with internal vibrators to remove the deeper air bubbles.

Screed concrete vibrators are available on eBay at reasonable prices. Youll want a configuration that matches the needs of the jobs that you will be using it for. Some of the configuration choices to consider are:

The blade, also known as a bar, is the part of the screed vibrator that makes contact with the concrete surface, and as such it must be durable and lightweight, with aluminum and magnesium the most common fabrication materials. Screed vibrator blades are detachable and can also be purchased separately.

Larger blades cover more area in a shorter time, while smaller blades are easy to handle and can be used in tight areas. Be sure that the model of screed vibrator you buy accommodates the blade size you wish to utilize. This information can be found in the product specifications at the manufacturers site.

heavy duty vibrating wire piezometer - soil instruments

The heavy duty design prevents case stresses from aecting readings in extreme installations (dams and high ground stresses). The transducer is tted with either a low air entry sintered steel or a high air entry ceramic lter. A cone shaped nose piece is available for push in installations.

The Heavy Duty Vibrating Wire Piezometer incorporates an over voltage surge arrestor to oer protection from an indirect lightning strike. The piezometer is also available with a thermistor for temperature monitoring.

Piezometers are used in geotechnical, environmental, and hydrological applications. They can be installed in boreholes, placed in ll materials or in open wells to measure water levels or porewater pressures to enable engineers to verify design assumptions and control placement of ll. With a nose cone tted the piezometer can also be pushed into soft ground with a CPT rig.