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CSL428AL

Imperial Structural Locking Crownserts

CSL Series / Locking Type / AL / Structural

Installed using the Crownserts Hand-Installation Tool:  CSTL428

CSL428AL CS Series is a locking imperial Crownserts® threaded insert for durable thread reinforcement. 17-4PH stainless steel with IVD aluminium coating; specified with 1/4-28 UNF internal thread and 5/16-24 UNF installation thread.

Crownserts can offer you the part CSL428AL with Certificate of Quality, Certificate of Conformity and Certificate of Origin on request.

Thread & Dimensions

A internal thread (Class 3B) 1/4-28 UNF
B external thread (Class 3A) 5/16-24 UNF
Ø max minor special .2785
Ø C (+.008/-.002) .252
D (+.015/-.000) .095
E .210
G (±.010) .380
J (±1) 24
Through-hole preparation Min. full THD depth .519; Min. full depth .415
Blind-hole preparation Min. full THD depth .519; Min. full depth .415
CSL428AL schematic

Material & Finish

Material 17-4PH, Cond H1025 per AMS 5643
Finish IVD ALUMINIUM coating per MIL-DTL-83488 type 2, Class 3 & SFL per SAE AS5272, Type I
Temperature range Up to 600°F
Heat treat RC 35-42
Magnetic YES

Tooling & Preparation

Hand-installation tool part number CSTL420
Step drill part number CSD0281
Tap through tool part number TTI0312
Blind tap tool part number TBI0312
Removal tool part number CSRT420

Crownserts is offering part CSL428AL as factory new.