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March 16, 2010 / apexprecitech


Rieter P3-1 is perhaps the most widely distributed top arm in the spinning industry today. It is a simple top arm to work with but a little complex to understand in its intricacies.

This top arm is supplied by both Lakshmi Machine Works Ltd and Rieter Textile Systems in their Ring Frames. Rieter considers this top arm so effective that the same arm is used in Rieter’s flagship ” ComforSpin” compact spinning frames with slight modifications.

This top arm is pneumatically loaded. A long hose runs through the hollow hexagonal arm bar that also doubles as a housing for this pressure hose. This hose is pressurized to around 1.4 to 1.8 bar to get desired loads at the rollers.

The top arm is loaded from the fulcrum. The fulcrum is loaded by the expanding hose inside the arm bar. When the arm engages with this fulcrum, the load is transmitted to the arm area.

In this area, there is a bridge which divides the applied load to the combines front and second rollers and to the third rollers. The division of load is varied by shifting the pivoting distance of division by simply altering the position of a locating pin. This is an ingenious setup whereby simply by changing the position of the pin, loading ratio is changed.

The load transmitted to the first and second roller is through another bridge which again splits the load between the fron and second (apron) rollers, Here again three pin positions are given by which the ratio of loading between them can be changed.

The recommended load setting values for cotton spinning in the P3-1 top arm is like this

As always, Apex Top Arm Load Gauges were the first   to measure the top arm loads in P3-1 successfully and accurately from the very beginning.  We were initially discouraged by the spinners in the measurement of P 3-1 saying this was a pneumatic system and measurement was not at all necessary even after cots regrinding.

But experience is a better teacher. When we demonstrated the possible variations with worker neglect, pneumatic hose wear, and top arm general wear, spinners quickly understood its value. One defective top arm can play as a black sheep and spoil the quality of a lot. Variations of even 5 to 10 % in top arm loads can alter CSP and USTER values. Yarn appearance is directly affected by variations in top arm loads.

Also one idle top arm is a potential loss to  the mill. The gauge may be small but its indispensability to a spinning mill is undisputed. Now, mills are buying these gauges right at the project stage.

You can read more about our Apex Top Arm Load Gauge (with video  demonstration) by clicking on this <link>

If you have found this article useful and would like to comment on it , please click on this <link>

J Venkatasubramanian


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