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STJ-PS4-630 soft insert jaws
STJ-PS4-630 soft insert jaws is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
At Krollit, we guarantee a safe and reliable shipping process. Orders are handled with the utmost care and traceability until delivery.
For international shipments, please send your request via the dedicated contact form.
Upon delivery, always sign the delivery note with the words “subject to inspection” to allow for proper handling of any irregularities or discrepancies in the product.
Our goal is to ensure you receive prompt service and a worry-free shopping experience.
Description
Soft top jaws Ø 630 mm for PS type 4-jaw chucks. Distributed in Italy by Krollit — official Bernardo distributor since 2007.
Logistics
Original spare parts available with 3-5 working day shipping. Customer service in Italian available.
Technical specifications
Technical specifications
Chuck size |
630 mm |
A |
160 mm |
B |
52 mm |
C |
82 mm |
d |
12.71 mm |
E |
34.4 mm |
F |
76.2 mm |
G |
19.04 mm |
h |
63 mm |
l |
6.3 mm |
J |
4 mm |
Bolt size |
M20 |
Warranty
Warranty terms and support procedures are available on the dedicated Krollit page.
View Krollit warranty termsFAQ / Frequently asked questions
Frequently asked questions
Soft top jaws Ø 630 mm — what distinguishes them from monoblock soft jaws?
Soft top jaws combine the top jaw construction (hardened base body + replaceable soft top insert) with the unhardened mild steel insert. Compared to monoblock soft jaws: the soft inserts are replaced separately when worn or when over-machined, without changing the base body. Compared to reversible hardened top jaws: the soft inserts allow in-situ turning for maximum concentricity on delicate workpieces.
For Ø 630 mm — when is it necessary to turn (bore) the soft inserts in situ?
In-situ boring of soft inserts is necessary whenever: new inserts are mounted, the chuck's clamping pressure is changed, or eccentricity is noticed in the workpiece. For machining parts that require concentricity better than 0.05 mm, in-situ boring is indispensable — it reduces runout to the minimum physically achievable with the chuck in use.
Can the soft inserts be reversed for internal/external gripping?
It depends on the model: DSTJ jaws have non-reversible soft inserts (internal grip only or external grip only); reversible STJ top jaws can have soft inserts mountable in both orientations. Check the specific model's specifications. Customer service in Italian available.
Delivery times?
Original spare parts available with 3-5 working day shipping. Customer service in Italian available.
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