34 in 34 adjustment will be made completely automatic operation is obtained over the widest range of conditions if the dotted extension of curve iia where the pressure trace would have gone if there had been enough restriction would reach a pressure of p 1 a little before the ram reaches position y and if p 4 is the lowest compaction pressure consistent with having a practicable operating zone between the curves iia and iiia the curve iiia represents the pressure trace of the no feed stroke following a maximum spring back condition with municipal refuse this maximum spring back condition probably occurs when the refuse is all dry paper or cardboard and the compacter is operating at its maximum compaction pressure it is also necessary to monitor excessive pressure i e pressure greater than p 2 to initiate an 34 out 34 adjustment of the restrictors this however is not as critical as the above and can be done at any point after the ram has passed point a in fig3 which corresponds approximately to point z in fig5 the pressure p 2 may be monitored for a possible 34 out 34 adjustment during the interval that the ram travels from x to b in fig5 or it may be monitored from y to b as in the case of p 1 this later monitoring avoids most undesirable adjustments that might be caused by the pressure spikes as shown by the dotted lines between m and n normal pressure settings for p 1.