Lock-pin and collar fastening system : final report.
-
1997-02-01
Details:
-
Creators:
-
Corporate Creators:
-
Corporate Contributors:
-
Subject/TRT Terms:
-
Publication/ Report Number:
-
Resource Type:
-
Geographical Coverage:
-
Corporate Publisher:
-
Abstract:In 1993, a steel girder I-beam deck was extended to cross a new on-ramp at the Marquam Bridge Interchange in Portland, Oregon. The steel members of this new structure were fastened together using the lock-pin and collar fastening system.
These fasteners are quicker and easier to install than the standard threaded ASM 325 bolts. While the lock-pin are about the same length and strength as the standard bolts, the collars are not threaded but rather are swaged onto the lock-pin by a special hydraulic installation tool. Once the collar is swaged on, no additional tightening with a torque wrench is required. A simple sound test by pinging it with a hammer verifies the tightness of fit. While reports of nuts working loose on standard bolts are common, the lock-pin collar fasteners remained tight after three years of service.
Costs can be reduced with less labor by using this system. Since the lock-pins do not need to be torqued, the second and third tightness checks are eliminated. Material costs are about the same when torque indicator washers are used with standard bolts.
-
Format:
-
Collection(s):
-
Main Document Checksum:
-
Download URL:
-
File Type: