PRESSURE DIFFERENTIAL PRODUCTS 2008 TRICO CORPORATION. ALL RIGHTS RESERVED.
TYPES OF VENTS Expansion chambers Some equipment by design needs to breath Majority of equipment will come with some type of breather vent on the top of the housing Breather filler caps Spin-on filters Vent plugs Desiccant breathers Open vents
PRESSURE DIFFERENTIAL PRODUCTS Maintains a constant atmospheric pressure within the equipment it is installed on Two types of products are available depending on application requirements Breather Vents Equalizer Expansion Chamber
BREATHER VENTS Assures pressure equalization within housing by exchange of air Minimizes bearing seal blowout Reduces vacuums created by abnormally tight bearing seals Brass construction FEATURES 6 thread sizes for a wide range of equipment Available in NPT and BSPT threads Maximum operating temperature 240ºF 6 micron porous bronze filter available Minimizes contamination coming into the equipment
BREATHER VENT - APPLICATION Breather Vent installed on a centrifugal pump
VENTING CONSIDERATIONS Should only be installed in environments that contain minimal contaminants In highly contaminated environments Use non-vented oilers Remove vent and replace with either an: 1) Expansion chamber 2) Desiccant Breather 3) Spin on filter 4) Plug Consider seal type before selecting venting types Breathing action allows debris, dirt and moisture to enter the equipment Reduces lubricant life Reduces component life Bearings Gears
EQUALIZER EXPANSION CHAMBER Designed to prevent pressure increases in bearing and gearbox housings due to differential pressures with atmosphere caused by temperature fluctuations Prevents contamination ingression Replaces breather vents to close the equipment Ideal for use with closed system oilers when contacting shaft seals are used on the equipment
EXPANSION CHAMBER OPERATION Rolling diaphragm provides variable volume in the sump housing As pressure starts to build the diaphragm rolls or expands to accommodate the air expansion When pressure drops, diaphragm relaxes to its original position Prevents the exchange of air from the outside surrounding atmosphere into the sump housing Maintains air pressure in the sump housing at zero PSI when properly sized
EXPANSION CHAMBER - FEATURES Full 25 cubic inch air expansion capability Available in 3/8, 1/2 and 3/4 NPT Corrosion resistant stainless steel body Unlike competitors Viton diaphragm
EXPANSION CHAMBER - SIZING Three pieces of information need to be gathered to size an expansion chamber Amount of oil in sump oz High and low temperature range of housing - ºF Total volume in housing oz Numbers can be inserted into worksheet on Trico s website or using chart on page 13 of current catalog www.tricomfg.com/worksheet-exp_chamber.asp Expansion Chamber at a brewery
SIZING CHART
APPLICATION VARIATIONS
CONSIDERATIONS ON VARIATIONS Some equipment by design needs to breath, and installing a closed system oiler could cause pressure build-up Bearing Housing Seals Contact Lip seals are not designed to handle high pressures and will leak if closed off with no expansion chamber installed Magnetic seals are a true hermetic seal adding a closed system is an option and an expansion chamber is recommended Bearing Housing Seals Non-Contact Rotating labyrinth/bearing isolators provide pressure equalization through the gap between the stator and rotor so adding a closed system is an option, as well as expansion chamber to help prolong the life of the seal