Transcript Valves

Tomislav Skračić, MA
Undergraduate English
Course for
MARINE ENGINEERS
4th Semester
Essential reading:
SPINČIĆ, A., PRITCHARD, B, An English Textbook For Marine
Engineers 2, Pomorski fakultet, Rijeka 2009.
LUZER, J., SPINČIĆ, A., Gramatička vježbenica engleskog
jezika za pomorce, Pomorski fakultet, Rijeka 2003.
LESSON 7
INLET AND EXHAUST VALVES
Lesson 7
Inlet and Exhaust Valves
KEY WORDS
inlet valve
exhaust valve
working stroke
furthermore
considerably higher
consideration (n.)
give rise to
rocker arm
push (v.)
pull (v.)
- usisni ventil, v. usisnog zraka
- ispušni ventil
- radni takt
- osim toga, nadalje
- znatno viši
- obzir, razmatranje
- biti uzrokom, dati povod
- klackalica, pregibna ručica, otpirač
ventila, balanser
- pritisnuti
- povući
Lesson 7
Inlet and Exhaust Valves
PARTS OF A VALVE
spring (n.)
- opruga; također: proljeće, izvor vode
stem (n.)
- loza / vreteno / struk ventila
guide (n.)
- vodilica, klizna staza
valve rides in removable guide
- ventil klizi u zamjenjivoj
vodilici
seat (n.)
- sjedište
valve head
- glava ventila, pladanj
flame plate
- plamena ploča
valve rotator
- rotator ventila
ratcheting mechanism- zaporna naprava, zaustavni mehanizam
vane (n.)
- krilce, lopatica
valve cage
- skidljivo kućište ventila
annular passage
- prstenast / kružni prolaz
rocker gear - polužje klackalice, sustav poluga balansera
Lesson 7
Inlet and Exhaust Valves
pitting (n.)
- rupičasta korozija
extend (v.)
- produžiti
life of an exhaust valve
- vijek trajanja ispušnog ventila
reconditioned by grinding-in - ponovo repariran / obnovljen
brušenjem
(reconditioning = $ 4.000, new valve = $ 10.000)
particles of carbonaceous matter - čađa, čestice ugljikovih tvari
get trapped
- zaglaviti, zapeti, hvatati se, zaustaviti se
index (v.)
- zakretati (do određenog stupnja)
momentum (n.)
- moment, zakretna sila
scrape off
- ostrugati, otirati
deposit (n.)
- naslaga (bank deposit – štednja)
provision is made
- postoji mogućnost
clodged
- začepljen
Lesson 7
Inlet and Exhaust Valves
identation (n.)
- rupičasta korozija (= pitting)
dismantle (v.)
- rastaviti, demontirati, rasklopiti
engine indicator = pressure indicator - pokazivač, indikator
guide pulley
- kolut za vođenje, kolutna vodilica
cord (n.)
- uže, konopac
drum (n.)
- bubanj
stylus (n.)
- pisač, pisaljka indikatora
calibrated spring
- kalibrirana opruga
coupling nut
- spojna matica, matica steznog vijka
flange (n.)
- prirubnica, "flanđa" (npr. na košuljici)
accurately
- precizno, točno
aperture (n.)
- otvor, rupa
feed line
- cjevovod napojne vode
1. DEFINITION
Valve is a device used to regulate or control the flow of
fluids (liquid, air or gas), in pipings, systems and in
machinery.
2. VALVE OPERATING GEAR
 Cam
 Roller
 Tapet
 Push rod
 Rocker arm / lever
 Valve spring
 Valve
3. PARTS
 Valve cage - valve housing.
 Valve stem / valve spindle – the rod by means of which
the disk or plug is moved to open or close a valve.
 Valve head / valve lid – disk part of the valve that gives a
tight closure on the valve seat.
 Valve seat – the circular metal ring on which the valve
head / valve disk / valve plug of a valve rests when closed.
3. PARTS
 Valve cage - valve housing.
 Valve stem / valve spindle – the rod by means of which
the disk or plug is moved to open or close a valve.
 Valve head / valve lid – disk part of the valve that gives a
tight closure on the valve seat.
 Valve seat – the circular metal ring on which the valve
head / valve disk / valve plug of a valve rests when closed.
 Valve guide – a channel which supports the stem of a
valve for maintanance and alignment.
3. PARTS
 Valve cage - valve housing.
 Valve stem / valve spindle – the rod by means of which
the disk or plug is moved to open or close a valve.
 Valve head / valve lid – disk part of the valve that gives a
tight closure on the valve seat.
 Valve seat – the circular metal ring on which the valve
head / valve disk / valve plug of a valve rests when closed.
 Valve guide – a channel which supports the stem of a
valve for maintanance and alignment.
 Valve rotator – a device rotating the valve stem.
Adjusting valve
clearance
POPPET VALVE – is a cam-operated or spring loaded
reciprocating engine mushroom-type valve used for control of
admission and exhaust of working fluid. Its direction of
movement is at right angle to the plane of its seat.
OHV engine means overhead valve engine, i.e. an engine
having valves in the head.
4. MATERIALS
 Valve stem / valve spindle – of heat resistant steel
 Valve seat – steel with stellite welded on it (65% cobalt,
32% chromium, 3% tungsten)
stellite ['stelait] - special material resistant to high
temperatures. It forms a thin layer between the
seat and head. Damage or burnout of stellite
may result in a major failure of valves and other
engine parts.

Valve cage – cast iron
5. STRESSES
High pressure and temperature due to combustion.
6. REQUIREMENTS
 Strong, sturdy construction / manufacture.
 Carefully cooled
7. COOLING
Is executed by F.W. circulation, as excessive
temperature may give rise to damage by cracking.