Tapered twin-screw extruder is the main equipment for producing plastic profiles. In profile production, the twin-screw rotates outward in the barrel. Screw clearance not only affects the plasticizing effect of materials, but also affects the quality of products, sometimes leading to machine failure, and even leading to the scrapping of barrel, screw and other heart components. Screw clearance adjustment method is to start with the process and strictly control the process quality, thus ensuring the quality of the whole machine. \x0d\ 1。 Main technical parameters of screw clearance: \x0d\ 1, screw radial clearance: SJ z60/130-0.15 ~ 0.36mm; ? \x0d\2。 Axial clearance of screw: the front and rear clearance are equal; ? \x0d\3。 Rolling gap: small end: 1? 0mm, big end: 1? 5 mm.? \x0d\ II。 Operation method: \x0d\ 1. Pre-inspection: detect the axial clearance of the screws on the special fixture and find out the axial correspondence between the two screws. The main purpose of pre-inspection is to check and adjust the side clearance of adjacent threads in each section of the fixture, so that the minimum clearance on both sides is consistent, that is, one twin screw is fixed and the other advances in the central position, and the relative retreat is measured and recorded as the basis of the machine. Specific method: put the twin screw into the planed barrel, then install the double-hole flange and spacer, and start to adjust the clearance of the twin screw. \x0d\a, push the left screw (right-hand screw) to the bottom, and now step back 5mm, with the half key up, use 5? 3 1 distance ring locking screw; ? \x0d\b, slightly turn the right screw (left-handed screw) to carry interference, and use the magnetic seat of the dial indicator to find the middle position of left-right rotation; ? \x0d\c, then push forward and pull back the right screw to verify whether the middle position is consistent. \x0d\d, find the center position, using 5? 3 1 The locating ring is locked. ? \x0d\e, measure and record the clearance on both sides of each section (based on the left screw), and record the clearance on the front and rear sides. ? \x0d\f, Conclusion: When the screw is reasonable, the relative retreat "l" of the "center" position is measured, and the left-handed screw (right) is L-5 worse than the right-handed screw, so that this relative value can be kept in the barrel of the extruder, and x = 2 (l-5). ? \x0d\2。 Adjustment of screw clearance on main engine:? \x0d\ Measure on the checking fixture, put the twin screw into the barrel of the extruder, and adjust the small end gap on the left as required, d = 0. 15 ~ 0.36mm, excluding the receding amount, and only keep the d value. ? \x0d\a, use the distance ring to lock the left screw (half key up), measure the tool withdrawal amount and record it. ? \x0d\b, turn the right screw, use the magnetic seat and dial indicator to find out the center position, measure the difference between the backward L2 and the left and right screws, and record it. \x0d\ Note: L2-L 1 = L-5 indicates that the axial clearance of twin screws is equal. \x0d\c, with 5? 3 1 distance ring locking left-hand screw (the one on the right), the standard is made on two distance rings of twin-screw and double-hole flange. ? \x0d\d, axial scribing (drawing)? \x0d\e, corner mark (cross)? \x0d\f, check whether the results on the front and rear fixtures measured at the feed inlet are consistent, and record the front and rear backlash of the right screw in the center. ? \x0d\3。 Eliminate the gap at the rear end of the screw, adjust the thickness of the gasket \x0d\a, pull out the right screw (left-handed screw), install the adjusting gasket on the left screw (right-handed screw), push the cylinder straight, and lock the distribution box and the cylinder with four nuts. ? \x0d\b, press the screw head with the top screw flange, completely eliminate the gap of the distribution box, measure the amount of retreat, and calculate the difference according to the records. \x0d\c, in the same way. Pressing the right screw can eliminate the gap, measure the amount of tool withdrawal and calculate the thickness of the processing adjustment pad; ? \x0d\4。 Record the following data and store it in the product file:? \x0d\a, charging port side clearance (front and rear)? \x0d\b, small end clearance (left and right)? \x0d\c, small end retreat (left and right)? \x0d\ III。 Operation essentials: \x0d\ Keep the axial correspondence of the screw detected by the fixture in the normal production barrel.