Short answer: ZSK 92 elements are defined by six dimensions — outside diameter, root diameter, axial length, pitch or disk width, stagger angle and shaft spline. Measure those from the worn part and any competent supplier can match the geometry without a Coperion part number.
Coperion's ZSK series is named by screw diameter in millimetres, which makes the model number a useful starting point but not a specification. ZSK 58, ZSK 70, ZSK 92 and ZSK 133 refer to nominal diameters of roughly 58, 70, 92 and 133 mm.
| Model | Nominal screw diameter | Typical duty |
|---|---|---|
| ZSK 58 | 58 mm | Masterbatch, engineering compounds, pilot to mid scale |
| ZSK 70 | 70 mm | General compounding, high-volume masterbatch |
| ZSK 92 | 92 mm | High-throughput compounding, filled and reinforced systems |
| ZSK 133 | 133 mm | Very high throughput, bulk commodity compounds |
The nominal diameter is not the number you machine to. Actual outside diameter, root diameter and the centreline distance between the two screws are what determine whether a part fits, and they must be measured from the existing part or from the barrel bore.
New elements on a worn shaft will not hold tolerance, and the failure is quiet: the elements sit slightly loose, the load distribution shifts, and wear accelerates from the first run. Before ordering a set, inspect the spline for fretting, measure the shaft diameter at several stations, and check for straightness.
If the shaft needs replacing, order it with the elements. Matching a new element set to a new shaft costs less than doing the job twice, and it lets the supplier hold the clearance relationship between the two parts.
A ZSK 92 barrel that has run with worn elements will have an oversized bore. Fitting new elements into it means starting life with excessive clearance, which is the single most common reason a replacement set underperforms. Measure the bore and either refurbish it — re-boring and re-lining restores nominal — or replace the affected segments at the same time.
Thirty to forty-five days with material available and drawings confirmed is our normal lead time for standard geometries; standard Chinese machines such as Giant, Jieya, Chuangbo, Chengmeng, Meizhilong, Jinwei, Useon and Kerke are normally held in stock and ship immediately. To quote accurately we need the six dimensions, the machine model, the element position on the shaft, and photographs of the worn part with a rule in frame.
For a mixed set — some conveying, some kneading — a shaft layout drawing or a photograph of the assembled shaft with each position numbered is the fastest way to avoid mismatched parts.
Choose the grade at the same time: nitrided vs PM vs HIP-clad compares the four options. Because ZSK 92 elements come from imported-machine stock, spare parts inventory planning is worth reading before the next shutdown.
Yes. Element geometry is defined by measurable dimensions, not by the OEM part number. Supply outside diameter, root diameter, axial length, pitch or disk width, stagger angle and shaft spline, and the part can be matched.
Nominally 92 mm. The actual outside diameter of a new element and the bore diameter of the barrel should still be measured, because the nominal figure alone does not define the fit.
If the bore is worn beyond tolerance, yes, or refurbish it. New elements in a worn bore start with excessive clearance, which is the most common reason a replacement set fails to restore performance.
ZSK 92 elements are made to order: 30-45 days once material is available and drawings are confirmed. Non-standard geometries or special steel grades can take longer, and the shaft should be inspected before the order is placed.
No. Diameter, centreline distance and spline differ between models. Elements are matched to a specific machine size and cannot be swapped between them.