This customer is the leading enterprise in the international three-pin joint industry. Customer's originally used chuck was fully imported Japanese chuck, which has very high requirements for stability, positioning precision and repeatability precision of the indexing chuck. Now all the chucks used by this customer office have been replaced by our chucks. At present, the customer is using more than 30 sets of chucks of our company. Four sets of them are used for turning work-hardened machining after heat treatment, i.e. replacing grinding with turning.