ASME STP-PT-086:2017 pdf free download

ASME STP-PT-086:2017 pdf free download

When the rivet achieved the temperature and lime requirements above. it was removed from the heat source with tongs and placed in the hole. The riveter on the head end seated the rivet with the gun off and then started that gun first to ensure that the head is seated properly on the sheet and there is no chance of the rivet being pushed out of the hole any distance. Once the head gunner was up and running the gunner on the shank end turned his gun on and began to form the head. Upon completely forming the head, the shank gunner stopped his gun but maintained bucking pressure on the rivet. The head gunner stopped his gun after the shank gunner. This process ensured that the rivet was not hammered without bucking on the other side. Typically, when the guns arc removed from the rivet, the very center of the head will be a dull red color. The plates were not prc-heatcd prior to driving the rivets.
The rivets in the 118-inch (3.2 min oversiied holes were longer than rivets for a 1/16—inch (1.6 mm) oversi,ed hole by the almunt necessary to ensure filling the hole and having enough material to fnnn a full head on the shank end. Because more material needed to be moved in this test, the rivets were mostly devoid of any red heat color when riveting was completed.
In the plates that were made to spring back, the first rivet driven was furthest from the fulcrum (9 inches) and the plates were spread approximately 116-inch (1.6 mm) to 3/32-inch (2.4 mm), A fit-up like this would be an extrenw case in a normal riveting job and would be considered nearly unacceptable practice Typically, this rivet drew the plates together on the end as the rivets were formed. The next two rivets were driven in holes located between the first rivet and the fulcrum, with a plate spread of 1/32-inch (0.8 mm to 1/16-inch (1.6 mm). The plate would have been less free to bounce than with the first rivet, however it would have rebounded more positively albeit a shorter distance, Both these rivets drew the plates closer together.
Test 3 was performed todeterntine if extended soak times adversely alTected the rivet, and was done in the same manner as Test 2 except that the rivets were healed in a gas fired forge, and had extended soak times of 10 minutes and 20 minutes at temperature before driving.
Test 4 had been in the original test program where hand riveting is accomplished using hand hammers with no pneumatic or hydraulic assistance. While this may he done on a very limited basis for historical purposes. the scope of its usc in Test 4 did no seem relevant enough to justify the expenditure given limited budget constraints.