Problem
10-3
A helical compression spring is wound using 2.5-
mm
-diameter music wire. The spring...
Problem
10-3
A helical compression spring is wound using 2.5-
mm
-diameter music wire. The spring has an outside diameter of
31
mm with plain ground ends, and 14 total coils.
(a) Estimate the spring rate.
(b) What force is needed to compress this spring to
closure?
(c) What should the free length be to ensure that when the
spring is compressed solid the torsional stress does not
exceed the yield strength?
(d) Is there a possibility that the spring might buckle in
service?
Solutions
Expert Solution
Solution:- The
given problem has been solved using the standard formulas and
principles used in the design of helical compression springs.
Standard data for spring wire material i.e. music wire has been
taken from standard textbooks.
A helical compression spring is wound using 1 mm-diameter music
wire. The outside coil diameter of the spring is 11 mm. The ends
are squared and there are 12 total turns.
(a) Estimate the torsional yield strength of the wire.
(b) Estimate the static load corresponding to the yield
strength.
(c) Estimate the scale of the spring.
(d) Estimate the solid length of the spring.
(e) Is there any possibility for buckling?
Q4 (a): A helical compression spring
made of music wire (ends are squared and ground) has mean coil
diameter 33.77 , wire diameter 5 , and the number of active coils
22. Assume no set removal.
a) Calculate the torsional yield strength, of the
spring wire (in units). Enter only numeric value upto
four places of decimal without units.
(b): A helical compression spring
made of music wire (ends are squared and ground) has mean coil
diameter 34.93 , wire diameter 5.87 , and...
An as-wound helical-coil compression spring with infinite
fatigue life is needed to resist a dynamic load that varies from
8.0 to 24.0 lbf at 45.0 Hz over a dynamic deflection of 0.3 in.
Because of assembly considerations, the solid length of the spring
cannot be more than 1.2 in. The spring should have squared and
ground ends and is to be made from peened music wire. Upon closure,
use a design factor of 1.2 guarding against yielding and a
fractional...
1. Evaluate a music wire spring with plain ends where the wire
diameter is 0.100” and the outer
diameter is 0.600”. The desired spring rate is 100 lbf/in and the
free length is 2.4”. Let the load
safety factor be 1.00.
a) What is the spring index, C?
b) What is the total number of coils, Nt?
c) What is solid length, Ls?
d) What is the maximum suggested load?
e) What is the maximum suggested deflection?
f) What is...
A compression spring has a diameter of 0.67 in and a coil
diameter of 0.067 in, with 30 total coils.
The spring is to be made of unpeened HD A227 wire and have squared
and ground ends. Find the
fatigue factor of safety when repeatedly cycled from 0 to 10.3 lbf.
Use the Gerber fatigue criterion
and the Zimmerli data.
10-35: A helical coil compression spring is needed for food
service machinery. The load varies from a minimum of 4 lbf to a
maximum of 18 lbf. The spring rate k is to be 9.5 lbf/in. The
outside diameter of the spring cannot exceed . The springmaker has
available suitable dies for drawing 0.080-, 0.0915-, 0.1055-, and
0.1205-in-diameter wire. Use squared and ground ends, and an
unpeened material. Using a fatigue design factor nf of 1.5, and the
Gerber-Zimmerli fatigue-failure...
A helical compression spring has 14 active coils and the free
length is 12.5in. The outside diameter is 7/16 in and the spring
has squared and ground ends. The end plates are constrained to be
parallel. The material is music wire with presetting. The wire
diameter is 0.042 in. Determine: (1) for static conditions compute
the spring index, the solid length, the stress when the spring is
compressed to the solid length. Check if static yielding occurs
while the spring...
1. If 55.1 cm of copper wire (diameter = 1.18 mm, resistivity =
1.69 × 10-8Ω·m) is formed into a circular loop and
placed perpendicular to a uniform magnetic field that is increasing
at the constant rate of 12.6 mT/s, at what rate is thermal energy
generated in the loop?
2. A rectangular loop (area = 2.7 m2) turns in a
uniform magnetic field, B = 3.2 T. When the angle between
the field and the normal to the plane...
3. Use oil-tempered 0.060” diameter wire to make a
spring with squared and closed ends, a
spring index of 4, and solid length of 1.25”. Use a load factor of
safety of 1.05 and make the free
length 1.75 inches.
e) What is the force to close to solid, Fs?
f) What is the critical frequency?
g) What is the factor of safety, solid, ns?
A current carrying gold wire has diameter of 0.84 mm.
the electric field in the wire is 0.49 V/m. What is
a The current carried by the wire?
b The potential difference between two points in the
wire 6.4 m apart?
c The resistance of a 6.4 m length of this wire.