I am looking for a good Fisher Valve solution for a screen reject valve in a recycle mill that flows metal and glass particulate? Standard V-150 w/ HD seal only last a year in application. Need a valve that will have a longer mean time between failures.
All suggestions are appreciated.
Pulp from cooking always contains some unwanted solid material. Some of the chips may not have been fiberized properly, and some of the fibrous material may not be completely in the form of individual fibers. The main purpose of the pulp screening process is to separate harmful impurities from pulp with minimal fiber loss, and at an acceptable cost level. Bark, sand, shives, and rocks are typically found within the cooked chips and must be removed.
There are multiple ways to separate out the impurities. This can be done mechanically by screen plates where separation is based on particle size, whereas gravimetric or centrifugal force field is needed for weight-based particle separation. However, pressure screening in multiple stages is the preferred method for removal of impurities such as sand and shives from the pulp. These operate by separating the feed pulp into either acceptable and rejects. The acceptable pulp passes through the device, and the rejected pulp is removed for further processing. This is accomplished in stages since most pressure screens cannot sufficiently concentrate the impurities in only one screening stage due to thickening of the reject on the screen itself. The purpose of the rejects stages is to concentrate the impurities in the reject stream, and to return the good fibers to the main process line.
The Fisher® Slurry Vee-Ball rotary control valve is specifically designed for slurry or erosive service where the shearing action is required by its V-notch ball. This design offers longer service life with heavy section flow ring, ball, and body liner in a choice of erosion resistant materials ranging from high- chrome iron to PSZ ceramic. The outlet bore of the valve may also be machined in order to match the pipe bore in order to avoid flange face scouring.
To enhance the performance and service life of the valve, a patented, low-friction bearing system fully supports both drive and follower shafts without de-rating pressure. To reduce maintenance costs, this bearing system is designed to easily drop into place. Splined driveshaft coupled with clamped actuator lever helps ensure zero lost motion. A patented, taper key ball-to-shaft connection eliminates lost motion and minimizes deadband. During maintenance procedures, this arrangement proves to be more reliable and easier to assemble than conventional connections. Trim parts are retained without the use of press fits or screw threads, and are therefore easily replaced.