Disc Pack Couplings made by Power Tech Group Oy

1. DPC couplings 2018 05 28

2. TK-TAPPIKYTKIMET
DPC – Disc Pack Couplings
DPC metal discpack coupling is a torsionally rigid and backlash-free shaft
coupling, which can compensate for medium angular and radial
misalignments between the connected shafts. The all-metal construction
is not susceptible to heat, and is maintenance free, so the coupling is
especially well suited for drives where traditional rubber element
couplings can not be used due to heat or high drive torque. A correctly
installed and dimensioned discpack coupling's lifetime is at least as long
as that of the connected machines, and it requires no maintenance apart
from visual inspection.
Keyless desing with integrated clamping elements as well as extra short
model with split intermediate piece are both available

3. BASIC DPC MODELS
DPC – Normal lay-out, two sets of metal disc
packs and intermediate shaft.
Several modifications like brake disc, different
hub – shaft connections, ”Jumbo” hubs.
Single disc pack version available as well.
DPCC – Reversed hubs inside intermediate
piece, which can be split to help the replacment
of the disc packs > no need to remove motor or
driven device to change the discs.

4. ADVISORY DIMENSIONS
Torque transfer
capacity is given
for standard
material.
Dimension d is the
largest possible
hub diameter.
Dimensions
Ln1/Ln2 and L2,
and thus L, can be
tailored to fit the
customer’s drive
Larger shaft
diameters and / or
torque transfer
capacities are
available upon
request.
DPC disc pack coupling with shortest intermediate shaft
Type Tnom Tmax nmax d1/d2 max Lmin Ln1/Ln2 DBSEmin
105 3373 5 060 4 000 105 321 95 131
115 4774 7 161 3 800 115 368 105 158
120 6683 10 025 3 700 120 404 115 174
135 8911 13 367 3 600 135 450 130 190
DPCC disc pack coupling with reversed hubs
Tyyppi Tnom Tmax nmax d1/d2 max L Ln1/Ln2 DBSE
100 (105) 3373 5 060 4 000 100 209 95 19
110 (115) 4774 7 161 3 800 110 232 105 22
115 (120) 6683 10 025 3 700 115 254 115 24
120 (135) 8911 13 367 3 600 120 286 130 26

5. DISC PACK FEM ANALYZE EXAMPLE

6. MATERIAALIT
Standard materials for DPC couplings:
Hubs and spacers: S355
Discpack: AISI 301
Special materials for DPC couplings:
DPCRST AiSi304 / AiSI316
DPCHD 42CrMo4 QT
DPC couplings are normally supplied without
surface treatment. Available treatments
include:
Painting (Hubs are normally not painted)
Bluing and parkerizing
Zink plating
Available heat treatments:
Nitriding

7. DPC-only metric DIN/ISO standard hardware
is used in DPC couplings, except for
couplings fitted with jumbo hubs.
All hardware should be grade 8.8 or higher.
Standard hardware is either zinc plated or
parkerized. Special hardware, such as
stainless steel, is available on request.
All screws should be torqued according to
values given in table 2.
Hardware of lower
grade than the
originals must not
be used.
Fitted screws for
the discpack must
not be turned
during tightening.
Table 2: Tightening torques
Type Thread Torque [Nm]
DPC-20 M4 4
DPC-22 M5 8
DPC-30 M5 8
DPC-40 M6 15
DPC-52 M8 35
DPC-65 M10 67
DPC-80 M10 67
DPC-90 M12 120
DPC-105 M12 120
DPC-115 M16 274
DPC-120 M16 274
DPC-135 M20 520
Tightening Torques
Values given for lightly oiled threads
HARDWARE

8. LIITÄNNÄT AKSELEILLE
The most common attachment is a fitted bore
and one keyway.
Different attachments available for DPC
couplings:
– Fitted bore and 1 or more keyways
– MAV locking devices
– Fitted bore with oil release bores
– Conical bore
– DIN5480/5482 spline
– SAE / ANSI spline
– Form shafts
– Flange attachments
The required attachment may also serve as the
base for choosing the correct coupling size;
large bores and small torque, for example.

9. MISALIGNMENTS
1
maxmaxmax



+


+


a
atod
r
rtod
w
wtod
k
k
k
k
k
k
Alignment information for special versions can be found in the assembly drawing.
Values given are valid for a coupling rotating at maximum 1500 1/min. If one alignment value is
known, the other two can be calculated as follows:
1,70 1,53 1,36 1,19 1,02 0,85 0,68 0,51 0,34 0,17 0
1 - - - - - - - - - - 0
0,9 - - - - - - - - - 0 0,29
0,8 - - - - - - - - 0 0,29 0,58
0,7 - - - - - - - 0 0,29 0,58 0,86
0,6 - - - - - - 0 0,29 0,58 0,86 1,15
0,5 - - - - - 0 0,29 0,58 0,86 1,15 1,44
0,4 - - - - 0 0,29 0,58 0,86 1,15 1,44 1,73
0,3 - - - 0 0,29 0,58 0,86 1,15 1,44 1,73 2,02
0,2 - - 0 0,29 0,58 0,86 1,15 1,44 1,73 2,02 2,30
0,1 - 0 0,29 0,58 0,86 1,15 1,44 1,73 2,02 2,30 2,59
0 0 0,29 0,58 0,86 1,15 1,44 1,73 2,02 2,30 2,59 2,88
AngularMisalignment∆kw[°]
Axial Misalignment ∆ka [mm]
Radial Misalignment ∆kr [mm]

10. Effect of angular misalignment and rotation speed on torque transfer. (Values given are approximate).
MISALIGNMENTS

11. MISALIGNMENTS
Effect of spacer length on lateral critical speed. (Values given are approximate).

12. An incorrectly
tightened screw may
come loose and
damage the coupling
or other parts of the
drive.
Altering the coupling
by machining or
welding is strictly
prohibited.
INSTALLATION & MAINTENANCE
General installation instructions for a DPC coupling:
- Align the coupled machines according to the values
listed.
- Measure the shaft and the coupling bore to check the
fit.
- Heat the hub to max. 130 ⁰C if required, and cool the
shaft with liquid nitrogen.
- Slide the machines against each other while paying
attention to the required distance between shaft ends,
check DBSE
- Install the disc packs and spacer. Follow the
tightening torques given.
- The disc pack must remain straight, and free of
tension after installation. A bent disc pack is a sign of
too much axial misalignment.
- Double check screw tightness and install the coupling
cover.
Servicing a DPC coupling:
- A DPC coupling is normally maintenance-free,
requiring only visual inspection.
- Inspect the disc packs for broken discs or bending.
Damaged disc packs should be replaced.
Inaccurate alignment
will lead to premature
coupling failure.
Locking hardware,
such as lock nuts,
should be replaced if
removed.

13. 2
1
3
4
5
6
7
8
9
Diassembling a DPCC coupling
DPCC - INSTALLATION & MAINTENANCE

14. Fitted screws are
tigtened and opened
by turning the nut.
A DPCC coupling can be radially
disassembled to change the discpacks, as
long as the DBSE is at least equal to the
thickness of the disckpack, as follows:
1. DPCC Coupling assembled between the
machines
2. Remove the radial screws from the spacer
3. Remove one disc pack from the spacer
4. Remove the other disc pack from the spacer
5. Separate the spacer halves
6. Spacer half removed
7. Spacer removed
8. Remove the disc packs from the hubs
9. The disc packs may now be replaced
without moving the machines
DPCC - INSTALLATION
& MAINTENANCE

15. SOME DELIVERIES DONE