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specified in 3.7.3 placed in the baskets, the derrick shall be operated through all attainable
positions. With the engine shut off, the baskets shall be lowered from maximum reach position
to not more than 32 inches for size 55 and 40 inches for size 70 above ground level. The test
shall be repeated, without baskets, with 1,350 pounds for size 55 and 1,700 pounds for size 70
suspended over the fiberglass extension head sheave. The unit shall then be tested with loads of
2,000 pounds for size 55 and 2,500 pounds for size 70, except the derrick shall not be lowered to
less than 45 degrees above horizontal. The unit shall then be tested at an angle of 75 degrees
(and above, if attainable) with the loads and with the telescoping section position restrictions
specified in table III. Stalling of the vehicle; inability to rotate, elevate, lower, extend or retract
into required positions; failure of the baskets to stay level; failure to lower at a safe rate with the
engine shut off; lifting of any vehicle wheel off the ground; part failure; or permanent set shall
constitute failure of the test.
4.4.3.3 Horizontal pull test. The derrick shall be placed in a horizontal position at right
angles to the longitudinal centerline of the vehicle. With the derrick fully retracted and the
winch line over the upper head sheave, a tension scale or dynamometer shall be placed in the
winch line, parallel to the longitudinal centerline of the vehicle and attached to a fixed object.
The derrick shall be rotated away from the fixed object and the winch line reeved in to take up
slack and maintain the derrick at right angles to the vehicle, until the horizontal component of the
force reading on the scale or dynamometer, at a right angle to the derrick, produces a torque of
not less than 21,000 foot-pounds for size 55 and 37,000 foot-pounds for size 70. The horizontal
component of the force is the scale or dynamometer reading times the cosine of the angle
between the winch line and the horizontal. Stalling of the vehicle; malfunction; evidence of part
failure or permanent set; operation of the turret hydraulic relief valve prior to reaching the
required torques; or failure of the hydraulic relief valve to operate prior to overload shall
constitute failure of the test.
4.4.3.4 Static tests. The vehicle shall be secured to the ground and the winch line rigged
to permit operation of the derrick with overloads. Using a tension scale or dynamometer and a
ground anchor, or measured weights, the derrick shall be subjected to twice the loads specified in
4.4.3.1 and 4.4.3.2 (without baskets). The derrick shall be extended and placed in its most
vertical position. A load of 13,000 pounds for size 55 and 16,000 pounds for size 70 shall be
suspended from the upper head sheave. Part failure or permanent set shall constitute failure of
the test.
4.4.3.5 Detection of failure. After completion of the tests specified in 4.4.2 through
4.4.4.4, dye penetrant or magnaflux shall be applied on the critical areas of welds. A
water-soluble penetrant shall be applied on all critical plastic areas. The water-soluble penetrant
or magnaflux shall provide a means to inspect for crack indications under dynamic and static
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