F
OR
M
ODELS
: JGI, JGM, JGN, JGP
AND
JGQ
S
ECTION
1 - D
ESIGN
S
PECIFICATIONS
& D
ATA
PAGE 1-15
Fastener Tightening Torque
Listed in the following tables are fastener tightening torque values required for proper
assembly of Ariel JGI, JGM, JGN, JGP and JGQ compressors. Refer to the section concern-
ing a subject component for detailed assembly procedures.
Threads are to be clean and free of burrs.
Torque values are based on the use of petroleum type lubricants on both the threads and
seating surfaces. Use lubricating oil or Lubriplate 630, except for compressor piston rods,
crosshead-balance nuts and piston-nuts; and stainless steel fasteners which use Never-
Seez, Regular Grade (by Bostik, available from industrial suppliers, such as
www.neverseezproducts.com
), and except where Loctite is specified. Molybdenum disulfide
lubricants and Never-Seez are not otherwise to be used for fastener lubrication unless spec-
ified, or excessive stresses can result with the listed values. When anti-seize lubricants are
T
ABLE
1-11 P
ISTON
TO
B
ORE
C
LEARANCE
AND
P
ISTON
/R
IDER
R
ING
E
ND
G
AP
, I
N
.
(mm) - JG & SG C
LASS
C
YLINDERS
BORE
DIAMETER
a
a. Conventional piston rings are standard for JG Class Cylinders, except 2-1/2JG-FS-HE Class cylin-
ders with bore diameters of 2.25” (57mm) & 2.5” (64); 3JG-CE, 2.75” (70) & 3” (76); and 3-5/8JG-CE,
3.375” (86) & 3.625” (92), which use piston/rider rings. Piston/rider rings are optional for other JG
Cylinders, except for 1-3/4JG-FS-HE, which uses conventional rings and wear band.
PISTON TO BORE
CLEARANCE
PISTON/RIDER RING END GAP
New
Maximum
2.25 (57)
0.090 to 0.096 (2.29 to 2.44)
0.023 to 0.039 (0.58 to 0.99)
0.156 (3.96)
2.5 (64)
0.090 to 0.096 (2.29 to 2.44)
0.030 to 0.046 (0.76 to 1.17)
0.184 (4.67)
2.75 (70)
0.090 to 0.096 (2.29 to 2.44)
0.044 to 0.060 (1.12 to 1.52)
0.240 (6.10)
3 (76)
0.090 to 0.096 (2.29 to 2.44)
0.044 to 0.060 (1.12 to 1.52)
0.240 (6.10)
3.375 (86)
0.090 to 0.096 (2.29 to 2.44)
0.044 to 0.060 (1.12 to 1.52)
0.240 (6.10)
3.625 (92)
0.090 to 0.096 (2.29 to 2.44)
0.047 to 0.063 (1.19 to 1.60)
0.252 (6.40)
3.875 (98)
0.090 to 0.096 (2.29 to 2.44)
0.051 to 0.067 (1.30 to 1.70)
0.268 (6.81)
4.125 (105)
0.090 to 0.096 (2.29 to 2.44)
0.055 to 0.071 (1.40 to 1.80)
0.284 (7.21)
4.75 (121)
0.090 to 0.096 (2.29 to 2.44)
0.057 to 0.073 (1.45 to 1.85)
0.292 (7.42)
5.125 (130)
0.090 to 0.096 (2.29 to 2.44)
0.062 to 0.078 (1.57 to 1.98)
0.312 (7.93)
6.125 (156)
0.090 to 0.096 (2.29 to 2.44)
0.069 to 0.099 (1.75 to 2.51)
0.396 (10.06)
6.5 (165)
0.090 to 0.096 (2.29 to 2.44)
0.074 to 0.104 (1.88 to 2.64)
0.416 (10.57)
7.125 (181)
0.090 to 0.096 (2.29 to 2.44)
0.083 to 0.113 (2.11 to 2.87)
0.452 (11.48)
7.5 (191)
0.090 to 0.096 (2.29 to 2.44)
0.088 to 0.118 (2.24 to 3.00)
0.472 (11.99)
8.5 (216)
0.090 to 0.096 (2.29 to 2.44)
0.114 to 0.144 (2.90 to 3.66)
0.576 (14.63)
8.875 (225)
0.090 to 0.096 (2.29 to 2.44)
0.120 to 0.150 (3.05 to 3.81)
0.600 (15.24)
