2
FORM NO. L-20203-H-0822
EXAMPLE:
The required differential engagement speed
using a Model 5H45P-E clutch at 60 psi is 150 RPM
(Clutch rotating at 1250, machine component at 1100).
The referred inertia is 3 Lb. • Ft
2
. The differential RPM limit
for the clutch is:
1.4(10
4
)
N =
= 213 RPM
(60‑22) 3
150 RPM is within the limit of the 5H45P-E operating at
60 psi with a load of 3 Lb. • Ft
2
.
INTRODUCTION
Nexen 5HP-E Multi Position Tooth Clutches are designed
for applications that require a high starting torque without
slipping.
Tooth clutches are normally engaged when stationary. In
certain circumstances, such as low RPM, tooth clutches
can be engaged at differential speeds up to 150 RPM. The
allowable engagement speed depends on the rotational
inertia of the mass being accelerated and the air pressure
applied.
If the tooth clutch is to be engaged in other than static
conditions, solve the following Differential Speed Formula
to make sure the application’s speed is within the limits of
the selected clutch.
DIFFERENTIAL SPEED FORMULA
Use the Differential Speed Formula to find the allowable
engagement speed (
N
) at a specific air pressure setting (
P
)
with a given inertia load (
WK
2
). This formula expresses the
relationship of the variables involved that effect the impact
of the face teeth during engagement. Tooth damage can
occur when tooth velocity and air pressure settings are
too high (i.e., a smaller clutch has a lower tooth velocity at
any given RPM and a small clutch has less driver inertia).
V(10
4
)
N =
(P‑22) WK
2
Where
N
= Differential RPM Limit Clutch
V
= Constant for Clutch (See Table 1)
P
= Operational Pressure P.S.I.
WK
2
= referred Inertia Lb. • Ft
2
CAUTION
If differential speed exceeds the clutch
limitations, ratcheting of the teeth can occur
and shorten clutch life.
Clutch
Constant
Clutch
Constant
5H30P-E
2.10
5H50P-E
1.26
5H35P-E
1.80
5H60P-E
1.05
5H40P-E
1.57
5H80P-E
0.78
5H45P-E
1.40
NOTE
The Differential Speed Formula does not estimate:
• RPM which prevents ratcheting.
• acceleration time.
• tooth stress after engagement.
TABLE 1 CONSTANTS FOR CLUTCHES
