QUARTERLY NEWSLETTER APRIL 2006 ASI SEAL SENSE Advanced Sealing International The ASI Model 550 Heavy Duty Slurry Seal also in this issue... Seal Customization for Specific Applications Employee Profile: Peggy Van Veckhoven ASI Success Story: History of the Model 550 ASI Distributors: Top 5 in 2005 Spring Seal School: Highlights and Pics VOLUME 1, NUMBER 2 Distributor News Quarter 1, 2006 ASI Spring Seal School The spring 2006 seal school was held March 6th and 7th in Baton Rouge. It was an unqualified success! Attendees came from all over the country and as far away as Trinidad, down in the Caribbean. Once again interest in ASI seals and how and why seals work was foremost on everyone’s mind. After experiencing both class- room and “hands-on” training, everyone had a better under- standing about our seals and mechanical sealing. ASI will hold another seal school later this year and we encourage all interested to sign up and “im- prove your sales with convinc- ing product knowledge.” For information about future seal schools, contact an ASI sales representative at (225) 272-2155 or visit our website at www.advancedsealing.com Top Distributors in 2005 Once again, we are very proud of our distributors’ hard work in 2005, as many of our top accounts increased their sales efforts to higher levels. ASI is committed to helping our distributors to become even more successful in 2006 and looks forward to the many sales opportunities the upcoming year will bring. 1. AGI Industries New Orleans, Louisiana 2. Equipment Pro Bloomsdale, Missouri 3. Fluid Concepts Baton Rouge, Louisiana 4. Valley Equipment Jonesborough, Tennessee 5. Sealing Solutions Chattanooga, Tennessee ASI Model 550 Heavy Duty Slurry Seal: In Detail The Model 550 is ASI’s double slurry seal, designed for slurries with up to 80% solids. It is a custom-fitted seal that completely fills the pump stuffing box, preventing the product from entering the box while providing an increased amount of barrier fluid around the seal components. The Model 550 is built to handle heavy slurries that tend to dewater in the stuffing box or plate out onto the seal components. Because the seal completely fills the stuffing box, the product does not come into contact with any metal seal components. This design eliminates the need for special metallurgy as only the two inboard seal faces and o-rings (in the bottom of the stuffing box) will see product. The standard inboard face combination for the seal is siliconized graphite against silicon carbide; however, other combinations are available. Coupled with the appropriate o-ring material, all metal components in the seal are constructed of 316ss. The inboard rotary unit is also available with a circulation device or “pumper” feature. The Model 550 operates as a double seal, utilizing a single component seal driven by a single cartridge seal. The inboard seal arrangement is com- posed of an o-ring mounted stationary face, which is pressed into the bottom of the stuffing box. A component style rotary seal is then mated against the stationary face. Next, a cartridge seal is mounted on to the stuffing box, and engages the component seal with a set a pins. The spring compression for the inboard seal is set when the gland bolts are tightened. The outboard cartridge seal is then used to drive the inboard component seal. A pressurized barrier fluid system is required for operation of this seal. The barrier fluid is piped into the inlet port in the BOTTOM of the seal gland, and exits out of the flush inlet (lantern ring inlet) located on the TOP of the pump stuffing box (to vent any entrained air). As with any pump specific seal, exact equipment dimensions are re- quired to properly fit the seal and, unfortunately, the Model 550 may not adapt to every piece of equipment. However, for standard pumps, the Model 550 provides as an economic alternative to conventional double seals, not only for slurries, but for any application requiring special metallurgy. Technical Notes: Seal Customization for Specific Applications Although seal companies rarely admit it, constructing an economically- feasible, universal-style mechanical seal that is ideally suited for all applications and sealing environments is a somewhat impossible task. ASI realizes that attempting to create a completely “bulletproof” seal is impractical, so we incorporate a certain amount of adaptability or room for customization into our standard seal designs. This flexibility allows us to construct our seals with materials suited to a wide application range while providing the capacity to fine-tune our products for specialized applications. To assist our distributors, we’ve assembled a list of some common “tweaks” or seal enhancements that may, under certain conditions, significantly improve seal performance. In fact, in some cases, these minor adjustments can be the difference between sealing success and failure. Light Hydrocarbons The face balance in ASI’s seals has been calculated to deliver optimal closure without excess wear for the majority of all sealable applications. However, certain products, primarily those with a specific gravity of 0.7 or less, may require more closing force to the seal faces than our standard balance provides. Typically, these products, especially light hydrocarbons, require a “non-standard” face balance to prevent these lighter fluids from escaping. Under these circumstances, ASI recalculates the seal balance to accommodate the application requirements, then “reprofiles” our standard faces accordingly. Face reprofiling is a fairly simple procedure with a minimal charge that does not usually alter standard delivery when presented at the time of a seal order. High/Fluctuating Operating Temperatures On occasion, single or unpressurized double seals running in applica- tions with extreme temperature fluctuations may experience intermittent leak- age (especially when maximum temperatures reach over 300o F). This leakage can often be attributed to distortion occurring to the stationary unit as the standard 316ss holder expands and contracts (with the temperature fluctua- tions) at a rate that is different than the stationary face insert. Normally, after the temperature stabilizes, the stationary unit will “lap” itself back flat, which in turn, causes the leakage to cease. This process, however, can be somewhat lengthy for tungsten and silicon carbide stationary faces. Additionally, some applications may not have a stabilization period or may require zero leakage. Under these conditions, we recommend the use of a CEA (Controlled Expan- sion Alloy) holder. A CEA stationary holder is built from metal that is compat- ible with both the application’s chemical requirements as well as the stationary face’s thermal expansion rate. What this means is that the face and holder heat up and cool down simultaneously, which will limit any face distortion that may occur. ASI also recommends our CEA holder for applications with con- stant temperatures in excess of 300o F. Not only does this holder limit distor- tion caused by the differing thermal expansion rates, it also prevents the face insert from slipping or loosening in the stationary holder in extreme tempera- ture conditions. Basically, if the seal application requires high temperature o- rings, it probably requires a CEA holder as well. CEA holders are stocked, standard delivery-time items for our universal seals; however, there is an addi- tional cost (varying by size and model) for this holder. In cases where cost is a primary issue or when distortion is excessive, the ASI Models 730 and 525, which have monolithic seal faces (i.e., no stationary holder), may be a more viable option for the application than the Model 585. Sticky or High Viscosity Fluids For universal style seals, ASI generally prefers the superior chemical compatibility and application versatility of silicon carbide as our standard ro- tary face material. Viscous or “sticky” products, however, present a few is- sues with silicon carbide material. When a pump is stopped and these prod- ucts are allowed to thicken or harden, they often “glue” the seal faces together or, at a minimum, impede their rotation. Once the pump is restarted, the breakaway torque required to free the faces occasionally damages the silicon carbide rotary face. In such applications, ASI recommends the use of a tung- sten carbide rotary face (once product compatibility has been established). The added tensile strength of the tungsten carbide material provides superior breakage resistance, especially in intermittent services where the pump is fre- quently restarted. For the most part, ASI stocks tungsten carbide in ANSI sizes and supplies it at a slightly added cost. TC is considered “our standard” rotary face for our larger, high-motion style seals and is usually stocked and available at no additional cost for these models. In Our Next Issue... Seal Customization for Hot Oils ASI Success Story The Model 550: A History of Outstanding Performance This success story actually began in 1987, when a local distributor presented ASI with the challenge of sealing a problem application that had been plaguing a nearby plant. The application product, phosphoric acid, operated at various temperatures and concentrations, including a highly concentrated form called “super- phosphoric acid.” The variances in the operating parameters yielded a product consistency that ranged from a thick syrup to solid crystals. Additionally, the product’s highly corrosive nature normally required the use of expensive alloy metals in any mechanical seal provided. At the time, the plant was unhappy with the high cost of its present seal and the poor performance that it provided. ASI decided that the only way to eliminate the need for exotic metal alloys was to fill the entire stuffing box with the seal, preventing the product from coming in contact with any metal. To achieve the ideal “inboard” seal face combination at an economic price, we coupled our component-style Model SD-1 (with its standard siliconized graphite face material) and a silicon car- bide o-ring mount. We then completed the “outboard” end of the double seal by “locking” the SD-1 unit to our Model 525, utilizing its cartridge-mounting to drive and set the inboard seal. This new seal arrangement resulted in what we now call our Model 550. For over 18 years, the Model 550 has provided unsurpassed perfor- mance in its original application, and is still used today by the same plant. And, over time, ASI has found the Model 550 ideally suited for many other slurry applications. Additionally, it has been sealing various forms of HTH paste and other bleaching materials, as well as higher concentration caustic products. More recently, we have discovered how well it lends itself to hazardous waste applications. For several plants, the 550 (supplied with a tungsten carbide “pumper” version of the SD-1) has been the only seal to overcome the large abrasives, varying chemicals and occasional dry-run scenarios typically found in hazardous waste service. As for this success story, ASI believes this is just the beginning; we are confident there will be many more applications and many more years of successful seal performance by the Model 550. Employee Spotlight: Peggy Van Veckhoven For this issue, our spotlight falls on Peggy Van Veckhoven, ASI’s superintendent of seal assembly operations. Peggy began her tenure with ASI in November 1993 as an assembly technician. Working her way along, she quickly moved into the repair service area and eventually became the repair operations manager before assuming her present duties. It is, perhaps, this extensive knowledge in all facets of both seal assembly and seal repair that provides her with the necessary skills to perform her job so well. At present, her crew is the most efficient and productive group of technicians that has ever worked for ASI. This crew’s superior competence level hasn’t evolved by accident; Peggy’s steady hand, people skills and knowledge of ASI mechanical seals make our assembly operations’ performance second to none. Peggy is married to Clay Van Veckhoven, a maintenance supervisor with the East Baton Rouge Parish Department of Public Works. She has a daughter, Sarah, who (you guessed it) also works for ASI as an assembly technician. They live close to the small town of Livingston, where they enjoy a country lifestyle in a beautiful rural setting. For leisure, Peggy and Clay spend their time camping and fishing, as well as maintaining the grounds on their property. As part of her job duties, Peggy oversees the training and manage- ment of all assembly personnel. She also coordinates quality inspections, purchasing activities, inventory management, shipping/receiving, equipment maintenance, warehousing and housekeeping. Additionally, it should be noted that her department’s safety record over the last five years is superlative. Several people and operations are involved in preparing just one seal to ship out the door, and Peggy orchestrates the entire process. So, next time you send in an order or rush a seal through the system, appreciate the timely service and flawless quality that Peggy and her assembly crew deliver on a daily basis. And, if you are visiting ASI, make it a point to say hello to Peggy and all of her talented employees. Of course, don’t plan on spending too much time; our assembly department is a very busy place.
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