Pump Seals - Face Materials
Pump Seals come in a wide range of designs however the most important factor when determining how long a seal is going to last, is deciding on the right seal face materials. The old adage "pay me now or pay me later" applies to seals. You must consider the environment the seal will be exposed to. Abrasive environments require seal faces that will hold up to the wear and tear of abrasive environments. It makes little sense to save money on the seal only to have to spend more money to replace the seal later. On the other hand if you are pumping very clean fluid that has a lubricating quality such as machine oil or Ethylene Glycol, save your money for better quality bearings.
The most common types of seal faces are: Carbon, Ceramic, Ni-resist, 17-4, Silicon Carbide, Tungsten Carbide, GFPTFE (glass filled PTFE.... often called Teflon (R)). Another group of seal faces would be those of coated seal faces. The coatings are "plasma coatings" and are generally a form or silicon or tungsten carbide sprayed onto a stainless steel seal head. They have been sold by various trade names by the major pump seal companies but in our opinion are not worth the money. We have found the coating will always eventually wear and once it has will need to be completely recoated. In contrast, if a Silicon Carbide or Tungsten Carbide seal face is worn, it can generally be re-lapped and polished , bringing it back to "like new" condition and allowing a second, third or even fourth use of the same seal head.
Ceramic - Generally a 99.5% aluminum oxide offering excellent wear characteristics due to it's hardness. It is chemically inert and can be applied to nearly any product. Ceramic cannot however handle the thermal shocks that Ni-resist or 17-4 seats can. They will also shatter like a plate if dropped on concrete.
If you have any questions please contact us at: E-Mail about your pump seals applications