Fixing jig, steel material holding device, and steel material holding method

A fixing jig configured to press and fix a steel material, comprising:

• a nut provided on a predetermined attaching base;
• a screw shaft screwed to the nut;
• a handle attached to the screw shaft, the handle being configured to rotate the screw shaft;
• and
• a contact portion relatively rotatably attached to the handle and configured to contact the steel material or a first extension member,
• wherein the first extension member is attachable to and detachable from the contact portion,
• the first extension member includes:
• a long cylindrical portion;
• an extension side contact portion provided at a tip end portion of the cylindrical portion;
• and
• a connecting portion provided at a base end portion of the cylindrical portion and connected to the contact portion,
• a second extension member is connected to the extension side contact portion of the first extension member via a hinge such that, in a first position, the extension side contact portion of the first extension member is connected to a connecting portion of the second extension member and, in a second position, the extension side contact portion of the first extension member is configured to contact the steel material, and
• the second extension member includes an extension side contact portion configured to contact the steel material at a tip end portion of the second extension member.

A steel material holding method using a steel material holding device,

• wherein the steel material holding device includes:
• a holding portion, which is formed in an annular shape and provided upright along a vertical direction, the holding portion being configured to accommodate a steel material therein and hold the steel material;
• and a rotating portion that rotatably supports the holding portion,
• the holding portion is openable and closable,
• the holding portion includes four fixing jigs provided on each inner surface of the holding portion, the fixing jigs being configured to press and fix the steel material in a first direction along a radial direction of the holding portion, and a second direction orthogonal to the first direction and along the radial direction of the holding portion, and
• the four fixing jigs each include:
• a nut attached to the holding portion;
• a screw shaft screwed to the nut;
• a handle attached to the screw shaft, the handle being configured to rotate the screw shaft;
• and a contact portion relatively rotatably attached to the handle and being configured to contact the steel material,
• the steel material holding method comprising:
• a pre-mounting rotating step of rotating the holding portion by the rotating portion to make the first direction coincide with the vertical direction before the steel material is mounted on the steel material holding device;
• an opening step of opening the holding portion;
• a height adjusting step of rotating the handle of the fixing jig positioned on a lower side in the vertical direction to adjust a height of the fixing jig positioned on the lower side in the vertical direction depending on a size of the steel material to be mounted;
• a jig avoidance step of rotating the handles of the fixing jig positioned on an upper side in the vertical direction and the two fixing jigs positioned in a horizontal direction to adjust positions of the fixing jig positioned on the upper side in the vertical direction and the two fixing jigs positioned in the horizontal direction so that the fixing jigs do not interfere with the steel material to be mounted;
• a placing step of placing the steel material on the fixing jig positioned on the lower side in the vertical direction;
• a closing step of closing the holding portion;
• and
• a clamping step of rotating the handles of the fixing jig positioned on the upper side in the vertical direction and the two fixing jigs positioned in the horizontal direction to clamp and fix the steel material.