Correct and reliable connection of the indicator to the engine is a basic requirement for accurate measurement. This can only be achieved by using the right indicator valves between the engine and the indicator.
The indicator valves are available with two-part spring loaded spindles or alternatively with servo-operated spindles. Both types are equipped with a back seat. The valves can be opened and closed in all temperatures without using brute force. The spring loading of the indicator valve spindle cone prevents any unwanted opening of the valve, even by unfavorable vibration frequencies. Therefore a counter nut on the spindle is not necessary.
