Wednesday, October 13, 2010

Centrifugal Pump Troubleshooting

You have four opportunities to trouble shoot centrifugal pumps and each opportunity can offer you a clue as to what is wrong with the pump...

A Little Bit More About Cavitation

Cavitation means different things to different people. It has been described as:

  • A reduction in pump capacity.
  • A reduction in the head of the pump.
  • The formation of bubbles in a low pressure area of the pump volute.
  • A noise that can be heard when the pump is running.
  • Damaged that can be seen on the pump impeller and volute.
  • Just what then is this thing called cavitation? Actually it is all of the above. In another section of this series I described the several types of cavitation, so in this paper I want to talk about another side of cavitation and try to explain why the above happens.

Cavitation implies cavities or holes in the fluid we are pumping. These holes can also be described as bubbles, so cavitation is really about the formation of bubbles and their collapse. Bubbles form when ever liquid boils. Be careful not to associate boiling with hot to the touch. Liquid oxygen will boil and no one would ever call that hot.

Fluids boil when the temperature of the fluid gets too hot or the pressure on the fluid gets too low. At an ambient sea level pressure of 14.7 psia (one bar) water will boil at 212°F. (100°C) If you lower the pressure on the water it will boil at a much lower temperature and conversely if you raise the pressure the water will not boil until it gets to a higher temperature. There are charts available to give you the exact vapor pressure for any temperature of water. If you fall below this vapor pressure the water will boil...

Tuesday, August 10, 2010

Jadwal Puasa Cepu

JADWAL IMSAKIYAH
ROMADLON 1431 H.
11 Agustus 2010 - 10 September 2010
cepu : 7°10'0"LS 111°35'0"BT Arah Qiblat: 294°16'37" Time zone : 7 Tinggi : 10 meter
Sudut Irtifak : Dhuha 4.5° Isya' 18° Shubuh 20° Ihtiyat waktu Dhuhur 4 menit
Dihisab oleh : Ibnu Zahid Abdo el-Moeid

Kuprit...jadi boss..

Met ultah prit..dan terima kasih atas jamuannya kemarin..meski awalnya ada acara poling pilih menu..dan masing2 sudah menentukan menu paporitnya..ternyata ada beberapa kaum dhuafa yang mendapatkan tidak sesuai dengan pilihannya..tapi itu semua tidak mengurangi keiklasan doa kita semua..

Tuesday, July 27, 2010

Kolesterol...oh..Kolesterol

Hampir dua bulan terakhir semenjak dokter kita mengumumkan hasil check up, kolesterol menjadi kata yang paling banyak di sebut di WP kita tercinta ini. Sebetulnya apa sih kolesterol itu..? dari mana datangnya..? seberapa burukkah dia..?.
dr. Samuel Oetoro, MS, Sp.GK dari Departemen Gizi Fakultas Kedokteran Universitas Indonesia, Jakarta, menjelaskan, "Kolesterol adalah suatu jenis lemak yang ada dalam tubuh dan dibagi menjadi LDL, HDL, total kolesterol dan trigliserida."

Wednesday, July 21, 2010

Happy birthday...

Hi..Bro..berdua yang ada di gambar itu, bulan ini adalah bulan yang paling menggembarikan dan penuh berkah buat bro.. berdua pastinya.. karena selain bulan ini bro.. berdua merakan hari jadi juga terbuka lebar kesempatan bro..berdua mendapatkan pahala yang besar.. ada sepuluh anak jalanan yang siap menerima santunan dari bro..berdua... Kalau kolesterol mereka sudah berlebih tapi untuk urusan "rasa" mereka sangat miskin..terserahlah bagi bro..berdua mengartikan... anyway.. happy birthday bro..berdua wish u all the best...