opens at 20° before top dead center and closes at 35° after the bottom dead center

opens at top dead center and closes at bottom dead center

opens at 10° after top dead center and closes 20° before the bottom dead center

may open or close anywhere

4 - 6 kg/cm2 and 200 - 250°C

6 - 12 kg/cm2 and 250 - 350°C

12 - 20 kg/cm2 and 350 - 450°C

20 - 30 kg/cm2 and 450 - 500°C

6 kg/cm

35kg/cmz

20 kg/cmz

27.5 kg/cmz

500- 1000°C

1000- 1500°C

1500-2000°C

2000-2500°C

increase

decrease

be independent

may increase or decrease depending on other factors