While Choosing Butterfly Valve We Should Pay Attention to the Five Major Parts

lug butterfly valve   mainly by : handle, valve, valve seat , the valve plate and stem components. Selection of valve when the valve is adapted according to the environment , pressure, temperature and media to matching that in the end what it optional , here to tell you about :
First, the handle: handle material is generally cast steel and aluminum , aluminum alloy strength is relatively lower than steel, but the former is relatively light weight , corrosion better.
Second, the Body: Body main material is : UPVC, gray iron , ductile iron, carbon steel and stainless steel.
  UPVC: that is, we often say that the plastic , it is about 50 degrees temperature , pressure 10 kg or less, if the diameter is greater than 300 , then it can only withstand the pressure of 6 kg less ;
  Gray cast iron : It temperature between -50 to 200 , the pressure of 16 kg, the over the water and gas ;
Iron : It is a kind of cast iron , is an iron , carbon and silicon alloys. It Temperature -30 ~ 350 ℃;
  Steel : It Temperature -29 ~ 450 ℃, for medium and high-pressure environment , and more for the chemical industry .
  Stainless steel: Stainless steel is 304 , it is resistant to corrosion, temperature is 550 ℃, generally over water , sanitary grade requirement must be stainless steel .
Third, Seat: Seat of the more common materials : NBR, EPDM, PTFE, PPL
NBR: Also known as ( Dingqing ) its temperature about 80 degrees , generally used over oil.
  EPDM: Also known as ( EPDM ) which temperature around 120 , is generally used too acidic and basic media ;
  PTFE: Also known as ( PTFE ) which temperature 180 degrees Celsius, which is an inert material , corrosion resistance is better, generally used over acid and alkali .
  PPL: it belongs to the high temperature , generally used for high-temperature environment , temperature 300 ℃
Fourth, Stem: valve plate materials commonly used 2Cr13, 304 and 316 , which are a kind of stainless steel , but the choice is 2Cr13, I discovered...