Wear plates

The face of the wear plate should be checked periodically and remachined if necessary. A whistling noise during operation is an indication the wear plate Is worn out or the valve spring requires tensioning. 

The wear plate of the main valve for erosion since its large diameter makes it vulnerable to a loss of vacuum... 

The twisting rubber hoses or o ringed elbows which connect the rotating pan necks with pipe and the wear plate to the face of the stationary valve The condition of the high impact nozzles mounted on the cloth wash manifold and, for wet cake discharge, the sluicing manifold The support rollers which take the vertical load of the entire machine and the horizontal thrust rolls that maintain the rotating frame concentric The toothed rim and sprocket which drives the pan filter... 

The factors Uiat enter into tlie design of vessels include type of material, configuration, inetliod of construction, design stresses, and tliickness of Uie metal. As with any equipment, design pressures and temperatures should take into consideration Uie most severe combination of conditions anticipated. Vessels must be completely drainable. Liners and wear plates may be required to prevent corrosion. 

Wearing plates With open type impellers or end clearance wearing fits, these perform the same purpose as wearing rings do with radial clearances. 

Figure 12-123B-2. Wear strip construction on induced draft fan for dirty gases. The inertia of suspended dust particles carries them toward the backplate or centerplate where the wear plate withstands the abrasion normally affecting the blade. (Used by permission Bui. 2-5100. The Howden Fan Co.)...

Erosion corrosion of pump impellers, casings and wear plates can be very troublesome. Positive-displacement pumps create much less turbulence than centrifugal or axial-flow pumps and should be used where possible in critical... 

The saddles must be designed to withstand the load imposed by the weight of the vessel and contents. They are constructed of bricks or concrete, or are fabricated from steel plate. The contact angle should not be less than 120°, and will not normally be greater than 150°. Wear plates are often welded to the shell wall to reinforce the wall over the area of contact with the saddle. 

UHMWPE—battery separators, light-weight fibers, permanent solid lubricant materials in railcar manufacture, automobile parts, and truck liners liners to hoppers, bins, and chutes farm machinery as sprockets, idlers, wear plates, and wear shoes sewage-treatment bearings, sprockets, wear shoes lumbering-chute, sluice, and chain-drag liners neutron shield... 

Mining and Ore processing Abrasion resistant linings for hoppers, chutes, cyclones, slurry pipelines, separators etc. Also bolt-in rubber wear plates for chutes and hoppers and conveyor rollers. Soft natural rubber for abrasion resistance. Hardness range 40 to 70°A... 

For higher pressure drops, a more erosion-resistant metal is recommended for the slide and seat. Depending upon the particular material employed, the vulnerable parts may be made entirely of this material or merely faced with it. A supported castable wear plate is usually installed on the inside of the body downstream of and opposite the slide. Erosion of slide valves in flue-gas service is usually not a problem if pressure drop does not exceed 6 to 8 p.s.i. (97). A dual-slide valve is normally used in order to maintain center-line flow, and the stack or line downstream of the valve is sized for a maximum velocity of about 100 ft./second to avoid excessive impingement as the gas expands upon leaving the valve restriction. When more than one valve is used in the stack, they should be spaced about 5 line-diameters apart to prevent the discharge from the upstream valve from impinging directly on the internals of the downstream valve. 

Cheek plates are wear parts and, therefore, must be replaced or repaired in regular intervals. Often, exchangeable hard-metal wear plates are provided at the point of highest pressure and wear (Figure 282). In particular, larger modern machines are equipped with cheek plates that can be easily replaced without dismantling other parts of the machine and are adjustable from the outside of the frame " to correct, within limits, wear. 

In each test, a sample of 4 kg coal (minus 4.75 mm in size) is processed in specially designed apparatus developed by Yancey and co-workers61. It consists of a pot 8 in (203 mm) in diameter and 9 in (229 mm) deep with a four-arm stirrer fitted with wearing plates. The stirrer rotates with a small clearance of 5 mm from the sides and bottom of the pot. In the test, the coal is placed in the pot and the stirrer rotated for 12000 revolutions at a speed of 1500 rpm. The wearing plates are weighed before and after the test, and the loss of mass in milligrams determines the abrasiveness index. 

Jaw crushers consist of a fixed jaw and one that moves see Figure 4.7. When the moving jaw is driven toward the fixed jaw, it crushes the ore in contact with both jaws. When the jaw moves backward, then the ore moves downward. The top feed size of the ore is limited by the opening at the top of the unit, while the crushed size is determined by the gap setting at the lower edge of the jaws. The crushing surfaces are lined with manganese steel wear plates. Reduction ratios of 4 1 to 6 1 are obtainable with this type of crusher. 

Figure 5.3. A gyratory crusher (by courtesy of Nordberg, UK, Ltd.) (a) mantle (b) shell (c) wear plates (d) spider...

Arrangement h is similar to g, but a wear plate is added on the outside wall of the downcomer and a horizontal impingement baffle is added below the nozzle to prevent entrainment. This arrangement is recommended for high-velocity feeds. Other advantages and recommended dimensions for this arrangement are similar to those for arrangement g above. 

High-velocity two-phase and vapor feeds should be avoided. Although wear plates can protect column internals from damage, there have been cases (61) when high-velocity vapor feeds cut holes through wear plates as thick as Vi in. 

Figure 9-. Schematic showing the experimental arrangement used to wear cartilage on cross-linked cartilageo The bottom plug fit into the holders. These were secured to the wearing plate with C clamps.

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