Many operators focus on reducing craps quantity and reduce the clearance between extrusion wheel and chamber. It works obviously and will lead to another result: extrusion wheel and chamber life time shortened. 
E.g.

People always think in a different way, so here we would like to remind you one thing. Think it over and calculate the actual cost of per ton, you reduce the craps quantity but shorten the life time of extrusion tools at the same time.
According to years experience and customers’ feedback, here we would like to offer our advice on clearance adjustment for your reference.

Measurement value should be comply with following guidance:
Lead wire measurement method is a simple but good solution.

1.1 lead wire thickness on A should between 0.30-0.40mm
1.2 lead wire thickness on B should be equal or bigger than A, the deviation should not exceed 0.06mm
1.3 from A to B, the lead wire should be aequilatus or change evenly
1.4 the lead wire thickness deviation of left and right sides at same position should not exceed 0.03mm

If any discrepancy appeared, make adjustment to get a reasonable working clearance

Remarks: the detail clearance value rely on product cross section size. Generally speaking, the bigger the cross section size, the bigger the clearance value.

Leave the clearance little bigger after changing all new parts, add or reduce spacer accordingly after running for 1 day!

SHIJIAZHUANG ZAIXI TRADING CO., LTD.
RENQIU CITY JINGKE DIES & MOLDS MANUFACTURING CO., LTD.
MR.CLARK LEE
+86-13503333408 (whatsapp)
Clark.lee@163.com 
www.chinacornerbead.com www.dubetterinc.com