DOC AIRBUS | AMM A320FThe Procedure to Use Torque Wrenches and Power Tools [IAE]
TASK 70-23-11-911-012-A
The Procedure to Use Torque Wrenches and Power Tools
1. Reason for the Job
This task gives instructions on the use of torque wrenches. If the component to be torque loaded includes self locking fasteners then a check must be made to make sure that the fastener can be used again (Ref. TASK 70-23-11-911-011-A).
2. Job Set-up Information
A. Referenced Information
3. Job Set-up
Subtask 70-23-11-869-051-A ** ON A/C NOT FOR ALL
Subtask 70-23-11-911-050-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 02:19:33 UTC
The Procedure to Use Torque Wrenches and Power Tools
1. Reason for the Job
This task gives instructions on the use of torque wrenches. If the component to be torque loaded includes self locking fasteners then a check must be made to make sure that the fastener can be used again (Ref. TASK 70-23-11-911-011-A).
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
Flexible Beam Torque WrenchSubtask 70-23-11-869-051-A ** ON A/C NOT FOR ALL
A. Not Applicable
4. ProcedureSubtask 70-23-11-911-050-A ** ON A/C NOT FOR ALL
A. Use Torque Wrenches and Power Tools
(1) Hand Torque Wrenches
1 To get the correct torque indication, the handle must be held lightly with one hand. The wrench must be pulled at right angles (90 degrees) to the center line of the wrench. The handle must be free to move on the pivot-point. This will make sure that the concentration of the force or load is at the correct position
The position of the hand must not be changed to a position that will change the concentration of the force from the pivot-point to a different position on the handle.
2 Do a test on wrenches on a setting rig at regular times to make sure they give an accurate torque indication. Interchangeable sockets, adapters and extension bars are supplied with all wrenches.
3 Use a torque wrench which will show the necessary torque value in the higher range of the scale; this will make sure of an accurate torque indication. The first and last quarter of the scale must not be used for mandatory loads. This is because the torque value shown for small loads cannot be read accurately in the first and last quarter. Some flexible beam type wrenches do not show the first and last quarter of the scale. Wrenches must be set to zero before they are used.
(b) Screwdriver type
1 Hold the tool the same as a screwdriver handle: this will make sure of an accurate torque indication. The handle must be turned smoothly until the necessary torque value is shown
2 Do a test on screwdriver type wrenches to make sure they give an accurate torque indication. When the screwdriver type wrenches are not used they must read zero on the scale. If necessary, adjust the wrenches as specified in the applicable instruction book.
(2) Power Wrenches
(a) Power wrenches must only be used to initially tighten nuts and bolts. The power wrenches must be set to give 50 percent of the correct torque value. An approved hand torque wrench must be used to tighten nuts and bolts to the correct torque value.
(3) Torque Multiplier
(a) The torque multiplier is a mechanical gearbox or hydraulic unit and must be used with a torque wrench. Higher torque values are possible with a torque multiplier than are possible with the usual range of torque wrenches. The torque wrench must have the correct scale for the ratio of the unit that is used. The torque multiplier must be calibrated at regular times and kept serviceable as specified in the applicable instructions.
(4) Torque Wrenches and Extensions
The procedure to calculate the corrected torque value that is necessary on the torque wrench is given as follows:
T = Specified torque for a part
E = Length of extension or adapter
L = Length of torque wrench
A = Distance through which force is given to a part
R = Corrected torque value
(b) Example
A specified torque of 1440 pound-inches (163 Nm) is necessary on a part. An extension of 3 inches (76 mm) from center to center of its holes is used. The torque wrench used has a length of 15 inches (381 mm) from center of handle or handle swivel pin to center of its square adapter. The extension or adapter and torque wrench are used in a straight line.
Then:
To get the specified torque (T) of 1440 pound-inches (163 Nm) the corrected torque value (R) that is necessary is 1200 pound-inches (136 Nm).
(1) Hand Torque Wrenches
CAUTION:
UNIVERSAL JOINTS MUST NOT BE USED WITH TORQUE WRENCHES BECAUSE INCORRECT TORQUE VALUES CAN BE SHOWN.
HANDLE EXTENSION MUST NOT BE USED ON TORQUE WRENCHES.
(a) Flexible beam type 1 To get the correct torque indication, the handle must be held lightly with one hand. The wrench must be pulled at right angles (90 degrees) to the center line of the wrench. The handle must be free to move on the pivot-point. This will make sure that the concentration of the force or load is at the correct position
The position of the hand must not be changed to a position that will change the concentration of the force from the pivot-point to a different position on the handle.
2 Do a test on wrenches on a setting rig at regular times to make sure they give an accurate torque indication. Interchangeable sockets, adapters and extension bars are supplied with all wrenches.
3 Use a torque wrench which will show the necessary torque value in the higher range of the scale; this will make sure of an accurate torque indication. The first and last quarter of the scale must not be used for mandatory loads. This is because the torque value shown for small loads cannot be read accurately in the first and last quarter. Some flexible beam type wrenches do not show the first and last quarter of the scale. Wrenches must be set to zero before they are used.
(b) Screwdriver type
1 Hold the tool the same as a screwdriver handle: this will make sure of an accurate torque indication. The handle must be turned smoothly until the necessary torque value is shown
2 Do a test on screwdriver type wrenches to make sure they give an accurate torque indication. When the screwdriver type wrenches are not used they must read zero on the scale. If necessary, adjust the wrenches as specified in the applicable instruction book.
(2) Power Wrenches
(a) Power wrenches must only be used to initially tighten nuts and bolts. The power wrenches must be set to give 50 percent of the correct torque value. An approved hand torque wrench must be used to tighten nuts and bolts to the correct torque value.
(3) Torque Multiplier
(a) The torque multiplier is a mechanical gearbox or hydraulic unit and must be used with a torque wrench. Higher torque values are possible with a torque multiplier than are possible with the usual range of torque wrenches. The torque wrench must have the correct scale for the ratio of the unit that is used. The torque multiplier must be calibrated at regular times and kept serviceable as specified in the applicable instructions.
(4) Torque Wrenches and Extensions
NOTE: The length of extensions, adapters and wrenches must be shown on the tools, or measured correctly before they are used.
(a) When an extension is used with a torque wrench it will change the length that has an effect on the load. The corrected torque value that is necessary to give a specified torque value for a part must be calculated when extensions are used The procedure to calculate the corrected torque value that is necessary on the torque wrench is given as follows:
T = Specified torque for a part
E = Length of extension or adapter
L = Length of torque wrench
A = Distance through which force is given to a part
R = Corrected torque value
| L x T L x T |
| R = ----- = ----- |
| A L + E |
(b) Example
A specified torque of 1440 pound-inches (163 Nm) is necessary on a part. An extension of 3 inches (76 mm) from center to center of its holes is used. The torque wrench used has a length of 15 inches (381 mm) from center of handle or handle swivel pin to center of its square adapter. The extension or adapter and torque wrench are used in a straight line.
Then:
| L x T 15 x 1440 |
| R = ----- = --------- = 1200 |
| L + E 15 + 3 |
To get the specified torque (T) of 1440 pound-inches (163 Nm) the corrected torque value (R) that is necessary is 1200 pound-inches (136 Nm).