Common sense and flushing of mechanical seals1

Common sense and flushing of mechanical seals 1. Common sense of mechanical seals Working principle of mechanical seals Mechanical seals rely on a pair or several pairs of end rock wool boards that are perpendicular to the shaft as relative sliding mechanical seals under fluid pressure and compensate for the elastic force of the mechanical seal compensation mechanism A shaft seal device that keeps fit under the action of (or magnetic force) and is matched with an auxiliary seal to prevent leakage. 2. The selection of common materials for mechanical seals is clean water; normal temperature; (dynamic) 9CR18, 1CR13 surfacing cobalt-chromium-tungsten, cast iron; (static) resin-impregnated graphite, bronze, phenolic plastic. River water (including sediment); normal temperature; (dynamic) tungsten carbide, (static) tungsten carbide seawater; normal temperature; (dynamic) tungsten carbide, 1CR13 surfacing cobalt chromium tungsten, rock wool cast iron; (static) impregnated resin graphite, carbonized Tungsten, cermet; superheated water 100 degrees; (dynamic) tungsten carbide, 1CR13 surfacing cobalt-chromium-tungsten, cast iron; (static) impregnated resin graphite, tungsten carbide, cermet; gasoline, lubricating oil, liquid hydrocarbons; normal temperature; ( Dynamic) tungsten carbide, 1CR13 surfacing cobalt chromium tungsten, cast iron; (static) immersion resin or tin-antimony alloy graphite, phenolic plastic. Gasoline, lubricating oil, liquid hydrocarbons; 100 degrees; (dynamic) tungsten carbide, 1CR13 surfacing cobalt chromium tungsten; (static) dipped bronze or resin graphite. Gasoline, lubricating oil, liquid hydrocarbons; containing particulates; (dynamic) tungsten carbide; (static) tungsten carbide. The purpose of flushing is to prevent the accumulation of impurities, prevent the formation of air pockets, maintain and improve lubrication, etc. When the temperature of the flushing liquid is low, the rock wool board also has a cooling effect. The main methods of flushing are as follows: 1. Internal flushing 1. Positive flushing (1) Features: Using the sealed medium of the working host, the rock wool insulation board is introduced into the sealing cavity from the outlet end of the pump through the pipeline. (2) Application: used for cleaning fluid, P1 is slightly larger than P, when the temperature is high or there are impurities, coolers, filters, etc. can be installed on the pipeline 2. Backwash The medium is introduced into the sealing chamber from the outlet end of the pump, and flows back to the inlet of the pump through the pipeline after flushing. (2) Application: for cleaning fluids, and P enters 3. full flush