Essential reading: SPINČIĆ, A., PRITCHARD, B, An English Textbook For Marine Engineers 2, Pomorski fakultet, Rijeka 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- usisni ventil, v. usisnog zraka exhaust valve- ispušni ventil working stroke- radni takt furthermore- osim toga, nadalje considerably higher- znatno viši consideration (n.)- obzir, razmatranje give rise to- biti uzrokom, dati povod rocker arm- klackalica, pregibna ručica, otpirač ventila, balanser push (v.)- pritisnuti pull (v.)- 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 = $ ) 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.