How is suspension spring rate calculated?

To calculate the amount of spring rate you will need on order to meet your working loads, simply divide the load you will be applying on your spring by the distance you expect your spring to travel or compress under that load. The equivalent to that formula will be your compression spring rate as shown below.

How do you calculate combined spring rate?

(Identical Spring Rates) You have two identical springs with a spring rate of 30 lbf/in (pounds of force per inch). To calculate the rate these two provide together, simply multiply the rate by 1/2 (0.5).

How do you rate a spring?

To test the spring rate, the spring is placed into a spring rate tester, like shown above, and is pre-compressed one inch (or millimeters if you’re using that measurement) and then compressed further to get the measurement for the next inch of compression.

What is the formula for calculating spring load?

Spring Rate Formula. Rate = Load ÷ Travel….Other formula variables you may come to appreciate are:

1. Formula Variables.
2. Spring Wire Diameter = d.
3. Spring Outside of Spring = D outer.
4. Mean Diameter Of Spring = D.
5. Young’s Modulus of material = E.
6. Shear modulus of material = G.
7. Spring Constant = K.
8. Active Coils = na.

What are suspension spring rates?

Spring rate refers to the amount of weight that is needed to compress a spring one inch. per inch spring – it will compress 1” when a 200 lb. load is placed onto the spring. If another 200 lbs. is put onto the spring, the spring will compress another inch.

Is higher spring rate better?

As you decrease the spring rate, the suspension is able to conform better to road irregularities, and thus grip improves. With a lower spring rate, the force pressing the tire down remains higher longer relative to the amount of travel it has, so it contacts the ground much sooner.

What do spring rate numbers mean?

Spring rate refers to the amount of weight that is needed to compress a spring one inch. If the rate of the spring is linear, its rate is not affected by the load that is put on the spring. For example, say you have a 200 lb. per inch spring – it will compress 1” when a 200 lb. load is placed onto the spring.

How do you calculate coil spring stiffness?

This is done by subtracting one wire diameter from the outer diameter or adding one wire diameter to the inner diameter. Once you’ve calculated the mean diameter, you must divide it by one wire diameter. This calculation will provide you with your spring index thus letting you know how tight it is.

How do you test a coil spring?

The easiest way to check for broken springs is by doing a visual check. Springs are located near the wheel just above the axle. It is usually helpful to lift your vehicle as it will make a broken spring more visible. Be sure to safely secure the body against any dropping or another sudden movement.

How do you calculate area of a spring?

To calculate the length of wire to make a compression spring, multiply the length of wire per coil by the total number of coils. When it comes to extension springs you will have to add 2 coils to the active number of coils to include the hooks if the spring has cross over hooks or side hooks.

How do you calculate spring compression?

Compression Spring Calculation Formulas in Metric Units

1. Outside spring diameter. D 1 = D + d [mm]
2. Inside spring diameter. D 2 = D – d [mm]
3. Working deflection. H = L 1 – L 8 = s 8 – s 1 [mm]
4. Spring index. c = D/d [-]
5. Wahl correction factor. where:
6. General force exerted by the spring. where:
7. Spring constant.
8. Mean spring diameter.

What is a good spring rate for lowering springs?

Springs should typically be compressed 25-30% of the free length when supporting the weight of the vehicle. Drag race cars will normally use a lighter rate spring (about 30%) to promote weight transfer while a street car will use a firmer rate spring (about 25%).

How to calculate spring rate and suspension frequency?

f = Natural frequency (Hz) K = Spring rate (N/m) M = Mass (kg) When using these formulas, it is important to take Mass as the total sprung mass for the corner being calculated.

How to calculate suspension frequency for a corner?

To calculate suspension frequency for an individual corner, you need Mass and Spring rate: f = 1/ (2π)√ (K/M) f = Natural frequency (Hz) K = Spring rate (N/m)

Why do you add weight to spring rate?

Add weight to compensate for the driver, passengers, and cargo in proper locations. If the suggested scales are unavailable, you may use the table below for approximations. Unsprung weight is the vehicle weight that is not supported by the springs.

How to calculate ideal spring rates for cars?

One issue with calculating ideal spring rates for a car is that calculations are based on ideal wheel loadings of the car. However, the ideal wheel loadings require ideal spring rates to calculate from.