Combines heliecals

[tbran]

1- the factory offers 2 types, regular or 68" pitch. These are called steep pitch or edible bean helicals. The problem with steep pitch helicals is in certain conditions they are so aggressive that they cause shearing or shredding of crop at high cylinder RPM. They were designed for low rpm movement of the crop where seed crackage would happpen at higher RPM. In some instances this can result in higher rotor loss as well. I am a proponent of installing steep pitch over the thresher and transitioning them into the regular pitch bars. This setup along with the helical extention moves the crop to the left and prevents the second pass threshing that occurs on the lH side of the grate. We have run several units this way for 2 years in corn, wheat, and soft red winter wheat with great results. Works for us.

 

[NDDan]

The factory stock setup for all P3s (short and long ones) are the single pitch all the way threw. The pitch is the same on short and long P3s. The steep pitch (68")are a field installed option for the long P3s. Them same steep pitch bars can be used on the short P3s to prevent second pass over concave but won't be found in any short P3 parts manual. I hear what tbran is saying about shearing affect with steep pitch but hasn't been a problem for me. I don't think the steep pitch is any steeper than the thresher helicals on the old P1s. We have lots of different combos of steep pitch bars. Steep pitch bars don't seem to gain you any earth shaking capacity. Our number one objective lately is to come up with an arrangement of steep pitch helicals to prevent second pass over concave. Ends up not to hard to do. Catch you later