-12-
(5) Different tightening conditions
The tightening torque may vary in accordance with the bolt torque coefficients (depending on
manufacturing processes, and specified by bolt manufacturers), bolt grade and bolt length even though
the dimensions of the bolts are the same. The tightening torque may also vary depending on the surface
finishing state of tightening materials (steel, aluminum, etc.), and materials to be tightened. In addition, if
there is seal packing, clearance, etc. between tightening materials, the tightening torque is decreased.
(6) Wear and looseness of the socket
With extended use, the hexagonal portion of the socket which is fitted to the head of a bolt or drill bit,
and/or hexagonal portion of the driver chuck which is fitted onto the anvil in the main body will be worn
and loose. Wear and looseness will cause a proportionate loss of tightening torque. In addition, use of
an incorrect size socket (slightly larger than the bolt being tightened) will also result in decreased
torque.
(7) Bolt and nut rotate together
The tightening torque that can be achieved may be considerably decreased if the bolt and the nut rotate
together during the tightening operation. The customers should be advised to carefully observe the
operation and ensure this does not occur.
4. Precautions for efficient use of charger and battery
(1) Battery may not be rechargeable immediately after use.
If the battery is exposed to direct sunshine for an extended period or if the temperature of the battery is
high immediately after it has been used in the Model WH 14DCAL/WH 14DY, the pilot lamp may not
light up even though the battery is connected to the charger. The battery is rechargeable when the
battery temperature is within the range specified in the table below. The customers should be advised to
place the battery in a shaded area with a good airflow and allow sufficient cooling before recharging if
the temperature of the battery is high. The cooling time required before recharging can be accomplished
varies from a few minutes to about 10 minutes, depending on the load, duration of use and ambient
temperature.
<Rechargeable battery temperature range>
Battery temperature
Battery
Model UC 18YRL charger
Model UC 18YG charger
Type BCL 1430
0
°
C to 50
°
C
-
Type EB 14B
-5
°
C to 55
°
C
0
°
C to 40
°
C
