With two-cylinder compounds used in railway work, the pistons are connected to the cranks as with a two-cylinder simple at 90° out of phase with each other (quartered). When the double expansion group is duplicated, producing a 4-cylinder compound, the individual pistons within the group are usually balanced at 180°, the groups being set at 90° to each other. In one case (the first type of Vauclain compound), the pistons worked in the same phase driving a common crosshead and crank, again set at 90° as for a two-cylinder engine. With the 3-cylinder compound arrangement, the LP cranks were either set at 90° with the HP one at 135° to the other two, or in some cases all three cranks were set at 120°.[citation needed]
At what angle were the groups of pistons set in relation to one another in a 4-cylinder compound?
90 90° to each other 90°
When the double expansion group is duplicated, producing a 4-cylinder compound, the individual pistons within the group are usually balanced at 180°, the groups being set at 90° to each other.
When the double expansion group is duplicated, producing a four-cylinder compound, the individual pistons within the group are usually balanced at one hundred eightydeg, the groups being set at ninetydeg to each other.
At what angle were the groups of pistons set in relation to one another in a four-cylinder compound?