User's Manual

20
G970 G976 G990
Circle
Pitch diameter
in (mm)
64 (1 626) 64 (1 626) 64 (1 626)
Thickness in (mm) 1.25 (32) 1.25 (32) 2.0 (51)
Adjustable guide shoes - standard / optional 3 / 5 3 / 5 5 / -
Adjustable clamp plates - standard / optional 3 / 5 3 / 5 5 / -
Upper circle wear plates - standard / optional 3 / 5 3 / 5 5 / -
Circle to drawbar support is provided by DURAMIDE™ wear plates and bearings at the clamp and guide shoes. DURAMIDE™ prevents metal-to-metal contact
and provides maximum service life.
Circle drive
The Volvo dual gear Circle Drive System uses direct acting hydraulic power for exceptional turning and holding capability under full load. Circle Drive System uses
two hardened drive pinions and is protected against impact damage by an overload relief valve as standard equipment.
Rotation degrees 360º 360º 360º
Drawbar
Dimensions of box section
in
(mm)
6.5 x 6.5
(165 x 165)
6.5 x 6.5
(165 x 165)
6.5 x 6.5
(165 x 165)
Plate thickness in (mm) 1 & .75 (25 & 19) 1 & .75 (25 & 19) 1.5 & .75 (38 & 19)
Cab & controls
Low profile cab with ROPS/FOPS
Interior height in (mm) 64 (1 625) 64 (1 625) 64 (1 625)
An optional full height cab is available with an inside height of 72.5” (1 842 mm).
All Volvo Grader cabs and canopies are designed to meet or exceed SAE J/ISO 3471-1:2004 and EN 13510:2000 ROPS requirements and SAE J/pr EN ISO
3449:2002 Level 2 FOPS requirements.
The retractable seatbelt is 3” (76 mm) wide and meets SAE J386 NOV. 97 and EN ISO 6683:1999. Industry standardized control lever arrangement.
Interior operator noise levels average 75 dB(A) per ISO 6394:1998 (enclosed cab).
Implement hydraulics
Circuit type: Closed center, load sense Proportional Demand Flow (PDF) Hydraulic System, with O-ring face seal hose connections.
Main implement pump type Axial piston type Axial piston type Axial piston type
Maximum pressure psi (Bar) 3,000 (207) 3,000 (207) 3,000 (207)
Output 2100 RPM
gpm (lpm) 55 (208) 55 (208) 55 (208)
Stand by pressure psi (Bar) 350 (24) 350 (24) 350 (24)
Filtration
Large capacity, replaceable in-tank filter. Filters both system and re-fill oil. With low level and high temperature operator warning.
Hydraulic fan drive pump
Type
Axial piston pump dedicated to the variable speed cooling fan. Reversible cooling fan optionally available.