Clarke CHT 141 User manual

1/2" SQUARE DRIVE
TORQUE WRENCH
MODEL CHT 141
OPERATING & MAINTENANCE
INSTRUCTIONS
Part No. 1800141
0606
1/2" SQUARE DRIVE
TORQUE WRENCH

Thank you for purchasing this CLARKE Automatic Torque Wrench.
This torque wrench is designed to tighten nuts with precision. It should NOT be used for UNDOING
nuts, as severe damage could occur. With correct use, this tool will produce an accuracy of
plus or minus 3%, and you can hear and feel when the desired torque setting has been
reached. With careful and considerate use, it will give years of reliable service.
GUARANTEE
This product is guaranteed against faults in manufacture for 12 months from purchase date.
Keep your receipt as proof of purchase. This guarantee is invalid if the product has been
abused or tampered with in any way, or not used for the purpose for which it is intended. The
reason for return must be clearly stated. This guarantee does not affect your statutory rights.
OPERATION
A. Torque Setting Adjustment
Example: To set the torque to 6.2 kilogram metres (kgm)
1. Ensure the lock nut (1) is loosened, by turning it anti-clockwise. Turn the knurled handle
until the zero mark on the chamfered scale (3) is in line with the next lowest graduation
on the linear scale (4). In this case it would be 5.7.
2. Continue to turn the knurled handle, five more graduations. (1 graduation equals
0.1kgm). The wrench is now set at 6.2kgm.
3. Tighten lock nut (1) to secure the setting.
B. Method of Use
Note: Preferably, DO NOT use knuckle or universal joints, as these could result in incorrect
torque settings.
1. Place the square drive on to the socket or extension bar, perpendicular to the nut/bolt
to be tightened.
2. Gripping the knurled handle with the right hand, whilst steadying the 1/2” square drive
end with the left, gently but firmly, pull the handle (i.e. in a clockwise direction) until a
click is heard, and a slight ‘break’ in the handle is felt. DO NOT turn any further.
IMPORTANT
1. Do not jerk the torque wrench in any way to tighten a nut. Apply even pressure
throughout theoperation.
2. Release the wrench immmediately the click is heard/felt.
3. It should be noted that the ‘click’ becomes weaker with the lower torque settings.
ACCESSORIES
1. 1/2" Square Drive, x 5" Extension bar.
2. 1/2" x 3/8" Square Drive adaptor.
3. Carrying Case

CONVERSION FORMULAE
1kg cm = 13.887in oz 1Nm = 14.161in oz
1kg cm = 0.08677in lbf 1Nm = 8.8507in lbf
1kgm = 7.233ft lbf 1Nm = 0.73756 ft lbf
1kg cm = 0.098Nm 1kgm = 9.80665 Nm
MAINTENANCE
Foot Kilogram Newton Newton Foot Kilogram Kilogram Newton Foot
Pounds Metres Metres Metres Pounds Metres Metres Metres Pounds
(ft.lbf) kgm Nm Nm (ft.lbf) kgm kgm Nm (ft.lbf)
5 0.69 6.78 10 7.38 1.02 1 9.81 7.23
10 1.38 13.56 20 14.75 2.04 2 19.61 14.47
15 2.07 20.34 30 22.13 3.06 3 29.42 21.70
20 2.76 27.12 40 29.50 4.08 4 39.23 28.93
25 3.46 33.90 50 36.88 5.10 5 49.04 36.17
30 4.15 40.68 60 44.26 6.12 6 58.84 43.40
35 4.84 47.46 70 51.63 7.14 7 68.65 50.63
40 5.53 54.24 80 59.01 8.16 8 78.46 47.87
45 6.22 61.02 90 66.38 9.18 9 88.26 65.10
50 6.91 67.80 100 73.76 10.20 10 98.07 72.33
55 7.60 74.58 110 81.14 11.22 11 107.88 79.57
60 8.29 81.36 120 88.51 12.24 12 117.68 86.80
65 8.98 88.14 130 95.89 13.26 13 127.49 94.03
70 9.67 94.92 140 103.26 14.28 14 137.30 101.27
75 10.37 101.70 150 110.64 15.30 15 147.11 108.50
80 11.06 108.48 160 118.02 16.32 16 156.91 115.74
85 11.75 115.26 170 125.39 17.34 17 166.72 122.97
90 12.44 122.04 180 132.77 18.36 18 176.53 130.20
95 13.13 128.82 190 140.14 19.38 19 186.33 137.43
100 13.82 135.60 200 147.52 20.40 20 196.14 144.67
105 14.51 142.38 210 154.90 21.42 21 205.95 151.90
110 15.20 149.16 220 162.27 22.44 22 215.75 159.13
115 15.89 155.94 230 169.65 23.46 23 225.37 166.37
120 16.58 162.72 240 177.02 24.48 24 235.37 173.60
125 17.28 169.50 250 184.40 25.50 25 245.18 180.84
130 17.97 176.28 260 191.78 26.52 26 254.98 188.08
135 18.66 183.06 270 199.15 27.54 27 264.79 195.30
140 19.35 189.84 280 206.53 28.56 28 274.60 202.54
145 20.04 196.62 290 213.91 29.58 29 284.41 209.77
150 20.73 203.40 300 221.29 30.60 30 294.22 217.00
155 21.42 210.18 310 228.67 31.62 31 304.03 224.23
160 22.11 216.96 320 236.05 32.64 32 313.84 231.46
CONVERSIONTABLES
Each torque wrench has been lubricated before leaving the factory. If the torque wrench
has not been used for some time, operate it several times allowing the lubricant to re-coat
the internal working parts.
• After use, keep adjustment at lowest torque setting.
• Do not turn handle below lowest torque setting.
• Clean wrench by wiping. Never immerse in any type of cleaning fluid.
• The wrench may occasionally require servicing/recalibration in order to ensure accurate
readings, in which case, contact your CLARKE dealer