Screws and nuts
Table 1: Stainless steel, A2 and A4, torque Nm (ft-lbs)
Property
class
M4
M5
M6
M8
M10
M12
M16
M20
M24
M30
50
1.0 (0.74)
2.0 (1.5)
3.0 (2.2)
8.0 (5.9)
15 (11)
27 (20)
65 (48)
127 (93.7) 220 (162) 434 (320)
70, 80
2.7 (2)
5.4 (4)
9.0 (6.6)
22 (16)
44 (32)
76 (56)
187 (138) 364 (268) 629 (464) 1240 (915)
100
4.1 (3)
8.1 (6)
14 (10)
34 (25)
66 (49)
115 (84.8) 248 (183) 481 (355) —
—
Table 2: Steel, torque Nm (ft-lbs)
Property
class
M4
M5
M6
M8
M10
M12
M16
M20
M24
M30
8.8
2.9 (2.1)
5.7 (4.2)
9.8 (7.2)
24 (18)
47 (35)
81(60)
194 (143) 385 (285) 665 (490) 1310
(966.2)
10.9
4.0 (2.9)
8.1 (6)
14 (10)
33 (24)
65 (48)
114 (84)
277 (204) 541 (399) 935 (689) 1840
(1357)
12.9
4.9 (3.6)
9.7 (7.2)
17 (13)
40 (30)
79 (58)
136 (100) 333 (245) 649 (480) 1120
(825.1)
2210
(1630)
Hexagon screws with countersunk heads
For hexagon socket head screws with countersunk head, maximum torque for all property
classes must be 80% of the values for property class 8.8 above.
6.2 Service
Regular inspection and service of the pump ensures more reliable operation.
Type of service Purpose
Inspection interval
Inspection
To prevent operational interruptions and machine breakdown. Measures to
secure performance and pump efficiency are defined and decided for each
individual application. It can include such things as impeller trimming, wear
part control and replacement, control of zinc-anodes and control of the
stator.
Twice a year
Major overhaul To secure a long operating lifetime for the product. It includes replacement
of key components and the measures taken during an inspection.
Every year, under
normal operating
conditions
NOTICE:
Shorter intervals may be required when the operating conditions are extreme, for
example with very abrasive or corrosive applications or when the liquid temperatures
exceed 40°C (104°F).
6.2.1 Inspection
Regular inspection and service of the pump ensures more reliable operation.
Service item
Action
Visible parts on
the pump and
installation
1. Check that all screws, bolts, and nuts are properly tightened.
2. Check the condition of the pump casing, strainer, cover, lifting handles, eye bolts,
ropes, chains, and wires.
3. Check for worn or damaged parts.
4. Adjust and/or replace if necessary.
Pipes, valves, and
other peripheral
equipment
1. Check for worn or damaged parts.
2. Adjust and/or replace if necessary.
6 Maintenance
Flygt 2190, 2201 Installation, Operation, and Maintenance Manual
31
