English to Spanish Tech/Engineering Mechanics / Mech Engineering industria minera

Se trata de una perforadora de roca. Por el contexto deduzco que "make/break a joint" se refiere al proceso de conectar/desconectar herramientas o algo similar. ¿Pero qué es exactamente "joint" en este caso? ¿Se refiere a la unión de una pieza con otra? ¿Y qué significa exactamente "make/break" en este contexto?

Gracias de antenamo.

Contexto:

Adding a drill rod and making a joint
When adding a drill rod, ensure that the threads are properly engaged, by spinning the rod in one full turn by hand, before making the remainder of the joint with the machine.
To make the joint, move the rodrunning joystick (19) to the right. The chuck will close and the rotation head start to rotate clockwise.
At the same time the feed cylinder disengages so the rod ends can screw together without damage to the threads.

Rotate the chuck slowly when making the joint, with a maximum of about 250 to 300 rpm.

3.5 Breaking the joint
To break the joint, the rodrunning joystick (19) is moved to the left.
When the joystick is moved fast to left, the rotation unit will start to rotate counter-clockwise.
After a short delay the chuck will grip the drill rod and then break the joint with a dynamic effect. Thread compensation is automatically engaged to prevent damaging the threads.
Do not unscrew the joint fully.
Leave at least one turn of the thread engaged.
When the rod is lifted out, the last thread is screwed out by hand."