Break-off bolt with torque-limiting section
A break-off bolt for securing a conductor within a connector includes a first thread section, a second thread section and a torque-limiting section arranged between the first thread section and the second thread section. The first thread section and the second thread section comprise the same external thread having a minor diameter. The torque-limiting section has at least one of no thread with an outer diameter larger than the minor diameter of the external thread or an external thread having a minor diameter larger than the minor diameter of the external thread of the first and second thread sections.
1. A break-off assembly, comprising:
a break-off bolt, comprising:
(a) a first thread section and a second thread section, the first and the second thread section comprising the same external thread having a minor diameter; and
(b) a torque-limiting section arranged between the first and second thread section and having no thread with an outer diameter larger than the minor diameter of the external thread; and
a nut having internal threads,
wherein a length of the torque-limiting section from the first thread section to the second thread section is less than a thickness of a nut threaded onto the first thread section or the second thread section,
whereby the internal threads of the nut cut into the torque limiting section as the nut travels from the first thread section to the second thread section, a torque for breaking the break-off bolt is lower than a torque for overcoming the torque-limiting section.
2. The break-off bolt according to claim 1 , wherein the torque-limiting section has an outer diameter smaller than a major diameter of the external thread of the first and second thread sections.
3. The break-off bolt according to claim 1 , wherein the external thread of the second thread section is a continuation of the external thread of the first thread section.
4. The break-off bolt according to claim 1 , wherein the torque-limiting section, the first thread section and the second thread section are formed integrally with one another as a monolithic component.
5. The break-off bolt according to claim 4 , wherein the break-off bolt is hollow and defines an internal cavity.
6. The break off bolt according to claim 5 , wherein the cavity defines an internal thread.
7. The break-off bolt according to claim 6 , wherein the internal thread of the cavity is formed at least partially at the second thread section.
8. The break-off bolt according to claim 6 , wherein the internal thread extends opposite to the external thread.
9. A break-off assembly, comprising:
a break-off bolt, including:
a first thread section and a second thread section, the first and the second thread section comprising the same external thread with a minor diameter; and
a torque-limiting section arranged between the first and second thread section and having no thread with an outer diameter larger than the minor diameter of the external thread; and
a nut engaging the external thread, and having internal threads,
wherein a length of the torque-limiting section from the first thread section to the second thread section is less than a thickness of the nut,
whereby the internal threads of the nut cut into the torque limiting section as the nut travels from the first thread section to the second thread section, a torque for breaking the break-off bolt is lower than a torque for overcoming the torque-limiting section.
10. The break-off assembly according to claim 9 , wherein the torque-limiting section has an outer diameter smaller than a major diameter of the external thread of the first and second thread sections.
11. The break-off assembly according to claim 9 , wherein the external thread of the second thread section is a continuation of the external thread of the first thread section.
12. A contact assembly, comprising:
a pipe-shaped connector having at least one bore extending through a wall of the connector;
a break-off bolt sized to be installed through the at least one bore, including:
a first thread section and a second thread section, the first and the second thread section comprising the same external thread with a minor diameter; and
a torque-limiting section arranged between the first and second thread section, the torque-limiting section having a length along a longitudinal axis, and no thread with an outer diameter larger than the minor diameter of the external thread; and
a nut having a thickness and internal threads,
wherein the length of the torque limiting section is smaller than the thickness of the nut,
whereby the internal threads of the nut cut into the torque limiting section as the nut travels from the first thread section to the second thread section, a torque for breaking the break-off bolt is lower than a torque for overcoming the torque-limiting section.
13. The contact assembly of claim 12 , wherein the nut is a unitary metal nut.