In 1990, Springs published a quiz for springmakers to see just how expert they are. Readers had so much fun with it; we decided to create another one. So sharpen your pencils, and test your springmaking knowledge with the questions below. Many thanks to Terry Bartel, Elgiloy Specialty Metals; Loren Godfrey, Colonial Spring; Simon Fleury, Liberty Spring; Linda Froehlich, Ace Wire Spring & Form; Bob Herrmann, Newcomb Spring of Colorado; Institute of Spring Technology (IST) staff members, Sheffield, England; Ed Lanke, Wisconsin Coil Spring; Michael Limb, Spring Consultants; and Mark Overmyer, Rockford Spring, for contributing to this quiz.
Incidentally, if you would also like to try the 1990 quiz, you can find it here.

For each question below, click on the circle next to the correct answer. When you are finished with the test, push the 'Score my test' button at the bottom of the page. Good luck!

Question #1
To ensure a compression spring does not resonate, a rule of thumb to make sure the natural frequency of the spring is how much higher than the operating frequency?

A. 1½ times.
B. 3 times.
C. 7 times.
D. 13 times

Question #2
Which of the following spring materials would not be suitable for use at an operating temperature of -80°C where impact loading is a possibility?

A. Chromium vanadium valve-spring wire.
B. 302 type stainless steel.
C. Inconel X-750.

Question #3
The rate of a compression or extension spring will vary depending on the tensile variation within the raw material.

A. True
B. False

Question #4
The relationship between the Shear Modulus (G), the Elastic Modulus (E) and Poisson?s Ratio (n) of a material is defined by which of the following relationships:

A. G = E / (2 + n)
B. G = E / (1 + 2n)
C. G = 2 (1 + n) / E
D. G = E / 2 (1 + n)

Question #5
A customer requests that your company electroplate a spring made of ASTM A1000 grade D material. Is this a good practice?

A. Yes
B. No

Question #6
If a compression spring has two loads, the load tolerance when expressed as a percent (%) value would be the same for the two loads.

A. True
B. False

Question #7
A springmaker should calculate or assign a load tolerance for the 2nd load first, and then calculate the 1st load tolerance second, when preparing a quote or when a customer requests a practical and cost-effective load tolerance.

A. True
B. False

Question #8
In order to calculate two load tolerances that are proportional to each other for a compression spring, one method the springmaker could use is the following empirical equation:
P1 tolerance = (P2/P1) (P2 % load tolerance).
Example: P1 = 10#. P2 = 20#.
Springmaker selects 10% as the P2 +/- load tolerance.
P1 tolerance = (20#/10#) * 10% = +/- 20%.

A. True
B. False

Question #9
Facts:

• In 1999, your company quoted to manufacture a double torsion spring for a customer.
• Quantity: 1 million parts per year for five years.
• Material: Stainless.
• Price: $60 per thousand. FOB your premises.
• Prior to receipt of the order, your customer requests a long-term agreement with price-downs of 5% in years two and three, 4% in year four, and 3% in the final year.
• Profit margin per original quotation: 10%.
• Order received in 2001.
• You supply only 650,000 parts in year one based on releases.
• You supply only 580,000 parts in year two based on releases.
• You receive a request from your customer for a further reduction in price of 5% for the remainder of the "contract," advising that failing your acceptance, the customer will market-test the price or conduct a Web auction for the spring in question, as well as all the other parts you're making for them.
• Since your original quotation, labor rates have increased by 7% and plating costs by 5%, to say nothing of various increases in hydro, etc.
  

What should you do?

A. Tell the customer very politely to "go to hell."

Question #10
What are you actually going to do?

A. Thank the customer for all his business
B. explain just how much you value the relationship
C. try very hard over lunch to negotiate a decrease somewhat lower than requested
D. All of the above

Question #11
What is the proper heat treatment for Inconel 625 material?

A. 1000-1400°F for one hour and then air-cooled
B. 950-1200°F for two hours and then air-cooled
C. 800-950°F for one hour and then air-cooled

Question #12
The developed length of a compression spring = × mean diameter × number of coils. picture

A. True
B. False

Question #13
Chlorine is beneficial to the corrosion resistance of 302 stainless steel.

A. True
B. False

Question #14
Electroplating with zinc and de-embrittlement heat treatment is recommended for springs made from which of these materials?

A. Drawn carbon steel.
B. 302 stainless steel.
C. Oil-tempered silicon chromium.

Question #15
The fatigue life of torsion springs (operated in the wind-up direction) could be reduced by which of these factors?

A. Wear from contact with a mandrel or tightening onto the mandrel.
B. Impact loading.
C. Use of external radial legs.
D. All of the above.

Question #16
A plot of % relaxation vs. log time will give a straight line and is more likely to give an accurate prediction.

A. True
B. False

Question #17
"My electroplating process is 100% efficient and so there is no need to de-embrittle your springs," says your sub-contract plater.

A. True
B. False

Question #18
Quench cracks are most likely to be caused by:

A. Raw material surface defects.
B. Heating for too long prior to hot coiling.
C. Water in the quench oil.
D. Delay between quench and temper.

Question #19
A high dew point in the protective atmosphere used in austempering will result in:

A. Complete decarburization.
B. Incomplete hardening.
C. Hydrogen embrittlement.

Question #20
Stress relief of music wire coil springs will cause which of the following?

A. Strain age hardening and an increase in elastic limit.
B. Relief (but not elimination) of residual forming stresses.
C. Stabilization of spring dimensions.
D. All of the above.

Question #21
90% of residual stress in a music-wire coil spring is relieved by stress relieving the springs at:

A. 400°F (200°C).
B. 660°F (350°C).
C. 540°F (280°C).

Question #22
Duplex peening consists of peening using a normal size shot and then re-peening using a much smaller shot.

A. True
B. False

Question #23
Which of the following statements is not true of alloys that have low Elastic (E) and Torsion (G) Moduli:

A. Using materials with low moduli values means that the same spring will have fewer active coils when compared with more common materials having higher moduli values.
B. There is an added benefit with low-moduli materials in that they all have lower densities.
C. Lower-moduli materials can withstand greater deflections than those with higher moduli without suffering permanent deformation.
D. In tensile tests, high moduli materials will have proportionally greater strengths for the same amount of elastic deformation than do low-moduli materials.

Question #24
Can an on-line oven be used to process springs made of 17-7PH material?

A. Yes
B. No

Question #25
The minimum tensile strength of music wire is higher than the minimum tensile strength of chrome silicon.

A. True
B. False

Question #26
Which makes a better spring? One made cold-wound or hot-wound? Why?

A. Cold-wound
B. Hot-wound

Question #27
Stress relieving has no effect on wire forms made of basic wire (1008).

A. True
B. False

Question #28
In order to improve the relaxation performance of 302 stainless, should you increase or decrease the normal stress relieving temperature?

A. Increase
B. Decrease

Question #29
Which of the following parameters influence relaxation performance: stress, time, temperature or wire size?

A. Stress
B. Time
C. Temperature
D. Wire size
E. All of the above

Question #30
If it is predicted a spring will relax 10% over 10 years, what is the estimated relaxation over 10% of that time?

A. 1%
B. 5%
C. 8%
D. 9%

Question #31
If you have a wire that gives inconsistent results during coiling, could this have been predicted by: Fracmat testing, chemical composition, tensile testing, cast or ovality?

A. Fracmat testing
B. Chemical composition
C. Tensile testing
D. Cast
E. Ovality

Question #32
The strain-gauge-type load cells in load-testing machines deflect when they are under load.

A. True
B. False

Question #33
In most cases, the positioning of a spring on the platen of a load tester will influence the recorded axial load.

A. True
B. False

Question #34
Which tester has the better accuracy: one with ±10% of reading or ±10% full scale?

A. one with ±10% of reading
B. ±10% full scale

Question #35
Should the torque of a torsion spring be measured during the loading cycle, the unloading cycle, the average of both, a replication of the application, or what it says on the drawing?

A. The loading cycle
B. The unloading cycle
C. The average of both
D. A replication of the application
E. What it says on the drawing

Question #36
When a compression spring is compressed, which of the following forces in addition to the axial force are induced: lateral force, rotating moment or tilting moment?

A. Lateral force
B. Rotating moment
C. Tilting moment
D. All of the above

Question #37
When a compression spring is compressed, it wants to unwind, which creates a torque. Is it possible to change the magnitude of this torque by altering the spring design?

A. Yes
B. No

Question #38
What is the main purpose for carrying out a chromate passivation treatment on electroplated coatings?

A. To color the surface for identification.
B. To provide a good keying surface for subsequent treatment.
C. To enhance the corrosion resistance.

Question #39
A spring made with 0.062 chrome-silicon wire needs to be shot-peened. The shot used would be S230. Is this a good practice?

A. Yes
B. No

Question #40
Post-forming aging heat treatments always result in products with higher tensile strengths than the starting material.

A. True
B. False

Question #41
A spring must resist corrosion and be exposed to a temperature of 700°F. Is it a good idea to use 17-7PH material to manufacture this spring?

A. Yes
B. No

Question #42
A customer using a highly over-stressed extension spring with extended hooks is experiencing occasional hook breakage. Should the hook diameter be increased or decreased to reduce hook breakage?

A. Increased
B. Decreased

Question #43
When computing fatigue life using a Goodman diagram (like the diagrams in the SAE Spring Design Manual), a stress that falls on the 10 million line with a standard B-10 fatigue life indicates what?

A. There will be no probability of failure before 10 million cycles.
B. There will be a probability of failure of no more than 10 pcs per million before 10 million cycles.
C. There will be an average probability of failure of 10% at 10 million cycles.

Question #44
What type of forces are exerted by garter springs?

A. Pulling
B. Radial
C. Bending

Question #45
Is it possible for a stainless steel spring to rust?

A. Yes
B. No

Question #46
The main reason for using NiSpan C for springs intended for sensitive instruments is constant modulus.

A. True
B. False

Question #47
Can an anodic e-coat be applied to a spring made of ASTM A401 steel?

A. Yes
B. No

Question #48
When six Belleville-washer-type springs are used as a parallel stack, the load will be the same as that for one washer while the deflection will be six times that of one washer.

A. True
B. False

Question #49
If replacing a single spring with a nested pair, the load is split in the ratio 2:1. What is the ratio for a nest of three springs?

A. 5:2:2
B. 4:2:1
C. 4:3:2

Question #50
Stainless steel springs can be peened without any concerns.

A. True
B. False