Vermeer Navigator D7 11 Series User Manual

D7x11 Series II Navigator Directional Drill Supplemental Operations 55-13
Portable Breakout System True Torque
Since tongs rotate while being used, actual torque applied to a joint is affected by the
change in geometry during use. For most applications, torque table provided in this
manual or on pump unit will be sufficiently accurate. However, if it is desirable to
obtain True Torque, use the following formula:
1. For ft-lb use the following formula: True Torque (ft-lb) = Pressure on gauge
(psi) x Effective Piston Area (1) x Moment Arm Length (ft)
2. For Nm use the following formula: True Torque (Nm) = 10 x Pressure on gauge
(bar) x Effective Area (1) (cm
2
) x Moment Arm Length (m)
Moment Arm Length (x) = Distance from drill rod joint center (2) to the center of the
line between pin locations (3).
Effective Piston Area Table:
Tong Effective Area
2.6 K 2.15 in
2
(13.9 cm
2
)
7.5 K 3.91 in
2
(25.2 cm
2
)
15 K 8.39 in
2
(54.1 cm
2
)
1
x
2
3
TONGS

Vermeer Navigator D7 11 Series Specifications

General

Brand	Vermeer
Model	Navigator D7 11 Series
Category	Drill
Language	English