Birim Çevirici

Metal Ağırlık Hesabı ( Tablosu )

Kuvvetin uygulama şekline göre  [değiştir]Üzerlerine etki eden kuvvetin uygulama şekline göre ikiye ayrılırlar.

Çeki yayları
Bası yayları
kurma yayları
Form yayları

Malzeme esasına göre  [değiştir]Metalik yaylar
Demir esaslı yaylar
Bakır esaslı yaylar
Nikel esaslı, özel alaşımlı yaylar
Metalik olmayan yaylar
Kauçuk, mantar, çeşitli sıvılar ve hava

Kullanım alanları  [değiştir]Yaylar yük altında, elestik şekil değiştirme özellikleri dolayısıyla enerji depolaya bildiklerinden makine konstrüksiyonlarında çeşitli maksatlarla kullanılırlar.

Saat mekanizmalarında, tek etkili hidrolik ve pnömatik silindirlerde, v.s. enerji depolama elemanı olarak,
İçten yanmalı motorların valfleriyle kam mili arasındaki irtibatı sağlamak, kavramalar ve frenlerde kuvvet ve hareket kontrol elemanı olarak,
Raylı taşıtların tamponları, kara taşıtlarının aks-şasi bağlantıları ve elastik kavramalar gibi darbeli ve titreşimli yerlerde darbe ve titreşim sönümleme elemanı olarak,
Vibratörler, sarsaklar ve elekler gibi titreşimin istendiği yerlerde titreşim elemanı olarak,
Dinamometre ve yaylı terazi gibi ölçü aletlerinde kuvvet ölçme elemanı olarak kullanılırlar.

Belirli bir kuvvet altında bir dereceye kadar büyük elastik şekil değişikliği gösteren, kuvvet kaldırılınca kısmen veya tamâmen eski vaziyetini alan mekanik enerji biriktirme elemanı. Yük altında şekil değişikliği esnâsında yaylar bir deformasyon (şekil değişikliği) enerjisi biriktirirler, boşalma sırasında bu enerjinin büyük bir kısmını geri verirler. Teknolojide yaylar şu maksatlar için kullanılır.

Kuvvet ölçmek; dinamometre ve kantarlarda olduğu gibi. Kuvvet uygulamak veya bir hareketi kontrol etmek. Kavramalarda veya frenlerde kavrama ve fren kuvvetlerini hâsıl etmek. Patlamalı motorlarda subapların kapanmasını temin etmek, kam sisteminde kam ile çubuk arasındaki irtibatı sağlamak vs.

Bâzı sistemlerin frekanslarını değiştirmek. Darbe ile meydana gelen kuvvetlerin şiddetini azaltmak. Taşıt makinalarında olduğu gibi sönümleme görevi yapmak. Biriktirilen enerjiyi bir hareketi meydana getirmek için harcamak, yâni motor görevini yapmak. Mekanik saatlerde olduğu gibi.

Yayların sınıflandırılması:

a) Ana zorlanmaya göre: Burulma, eğilme, çekme ve basma yayları.

b) Yayın dış şekline göre: Silindirik, konik, helisel çubuk, spiral, disk, yaprak, bilezik yaylar.

c) Yay telinin kesitine göre: Dairesel ve dikdörtgen kesitli.

d) Yüklenme şekline göre: Çekme ve basma kuvveti ile zorlanan yaylar.

Teknolojide genellikle birçok yaylardan meydana gelen yay sistemleri kullanılır. Sebebi, kullanma hacimlerinin sınırlı olması tek yaydan daha güçlü olması ve istenen şartların elde edilmesidir.

Prensip olarak sistemin rijitliği yayların bağlanış şekline göre tâyin edilir. Bağlantı şekli paralel veya seri olabilir.

Paralel bağlantıda şekil değişiklikleri birbirine eşittir:

Dytop= Dy1= Dy2=...

Standart yay grubunun Toplam kuvvet ise her bir yayın direnci kuvvetinin toplamına eşittir:

Ftop= F1 + F2 +...

Sistemin yay sâbiti: ktop:

ktop= k1 + k2 + ...’e eşittir.

Yayların seri bağlanması hâlinde:

Ftop= F1= F2=.......

Toplam deformasyon Dytop= Dy1 + Dy2 +...

Yay sâbiti ise 1/kt= 1/k1 + 1/k2 + ... olur.

Baskı yayı

 

                           

                               
Çekme yayları

                         
Form yaylar

                   

Torsiyon (kollu) yaylar

                  

 

Naturally, spring design software is available — you can find out where to get it in the Addendum. For the purists (or those who don't want to pay for a program), here's a very short summary of the mathematics of spring design. These equations, by the way, are taken from The New American Machinist's Handbook, published by McGraw-Hill Book Company, Inc.in 1955. I don't pretend to understand them.

Compression Springs

Compression springs are designed to create resistance to a compressive force. The Newcomb Spring Corporation uses the latest electronic gauges and equipment to monitor and control the length of these coil springs during the manufacturing process to ensure complete compliance to your specifications.
Standard compression spring bodies are:
- open-coiled
- helical shaped
- usually coiled with a constant diameter, though they can be produced in hourglass, cone and barrel shapes
Compression spring ends are often ground to increase operational life and to allow the spring to sit squarely on the load-bearing surface. Grinding also increases the number of active coils and the wire diameter available in a given volume of space which can result in higher loads or lower stresses. Our facilities operate with a wide variety of equipment - from hand-operated grinding tools to automatic, high-speed vertical spindle disc grinders.
There are many issues related to the design of a compression spring that should be considered, as these relate directly to the spring's performance. Manufacturing tolerance requirements, squareness of ends, deflection and the slenderness ratio are often overlooked in the design process. Newcomb's sales and engineering staff will gladly review your compression spring specifications with you and recommend the best options to control your costs and ensure the spring functions to fit your needs.

Newcomb Spring offers state-of-the-art spring manufacturing capabilities and produces parts out of:
- round wire
- square wire
- rectangular wire
- special section wire
Our material size range is .004-inches to 2.0 inches.

Compression Spring Formulas for Dimensional Characteristics
When applying the given data to solid height, one should remember that the formulas do not consider the fact that the actual solid height may not be the same as calculated, due to improper seating of the coils, variation in the grinding process, normal variation in wire size and electroplating.

Spring Characteristic	Open	Open & Ground	Closed	Closed & Ground
Pitch (p)	L - d na	L na	L - 3d na	L - 2d na
Solid Height (H)	d(Nt + 1)	d x Nt	d(Nt + 1)	d x Nt
Total Coils (Nt)	na	na + 1	na + 2	na + 2
Free Length (L)	(p x na) + d	p x na	(p x na) + 3d	(p x na) + 2d

d = Diameter of Round Wire (in. or mm.) L = Free Length Nt = Number of Coils

na = Number of Active Coils p = Pitch

 

Our nine ISO-certified manufacturing facilities are ready to offer design assistance, custom-package your spring and wire form part and ensure the springs we produce are 100% compliant to your specifications. Though we can manufacture coil springs, wire forms and stamped parts using virtually any material, the standard meterials we use in the spring manufacturing process are:

- spring steel - high carbon steel - low carbon steel - nickel plated carbon steel - stainless alloys - non-ferrous metals

- elgiloy - hastelloy - monel - inconel - titanium

Spring Engineering and Manufacturing

Accurate and effective spring design can only be accomplished in today's world using computer programs capable of running hundreds of simultaneous calculations. Following are just a few of the most basic formulas for getting a head start on compression spring design. Call us for design assistance. We can run a thorough analysis and assist you in designing the best spring for your application.

Spring Constant Calculate a spring constant from the spring's geometry and shear modulus.

Spring Geometry Calculate pitch, rise angle and solid height.

Force and Stress Calculate the maximum force a spring can take and the shear stress with consideration to the Wahl correction factor.

Variables used in design formulas Spring wire diameter d Spring outside diameter Douter Mean diameter of spring D Young's modulus of material E Max force at solid Fmax Shear modulus of material G Free length Lfree Wire length Lwire Solid height Lsolid Maximum displacement Ldef Maximum load possible Lmax Wahl correction factor W Spring Constant k Active coils na Total coils nt Density of material p Poisson ratio of material v Rise angle of spring coils ? Maximum shear stress ?max

Skegness Springs manufacture all your springs to order, offering a complete design service in the process.
Perhaps you know exactly what you need, or perhaps you don’t know where to start. Either way, this brief guide should help.
If more detailed information or design assistance is required, please don’t hesitate to contact us.

COMPRESSION SPRINGS Compression springs provide an outward “pushing” force. If you need a compression spring, think about the following: Rate (strength) How much force does the spring need to give? Measured in N/mm, lb/in, kg/mm or as a force at a length. Diameter (inside or outside) Does the spring need to fit over a rod, or inside a hole? If so, specify the sizes and we will calculate safe clearances. Free Length The original length before any force is applied. Coils (active or total, or the gap between coils) The number of coils in the spring influences the strength, and the solid length of the spring. Material (size and type) See overleaf for further details about materials. End Configuration See diagrams below: Open End Closed End (Not ground) Closed and Ground End Where space is limited or extra strength is required, it is often possible to use a nest of springs – one inside another. Please contact us for further information.

EXTENSION SPRINGS Extension springs are the opposite of compression springs in that they provide an inward “pulling” force. Rate (strength) As for compression springs. Initial Tension The initial force required to open the spring slightly. This can be varied a certain amount if required. Diameter (of the spring and hooks/loops) Does the spring fit into a hole? What do the hooks/loops fit over? Number of Coils Free length Body length, or the original free length of the spring (including hooks or loops) before any extension. Material (size and type) See overleaf for further details about materials. End Configuration – See diagrams below: Machine Loop Crossover Loop Extended Round Loop Cone End with Swivel Loop Plain End with Threaded Insert

 

TORSION SPRINGS Torsion springs are different to both compression and extension springs – they provide a circular (torsional) force through the legs of the spring. Torsion Rate / Torque Measured in Nmm/degree or lb-in/degree. Inside Diameter Allowance should be made for the decrease in diameter of the spring in operation. Leg Configuration (and angle) A few common examples are shown below.		Body length Coils, or pitch Torsion springs are usually closed-coiled (like extension springs) with no gap between each coil. Left- or Right-hand wound? See diagrams on reverse for more details. Material (size and type) Torsion springs should usually be designed to “wind up” when a load is applied to it. Double-torsion springs can also be manufactured – please give us a call for more details.
Axial Legs	Tangential Legs	Radial Legs	One Radial over centre and one Tangential leg
FLAT STRIP & WIRE SHAPES We are able to manufacture an infinite range of flat and wire shapes to any design. Depending on the design and quantity required, these are manufactured either by hand, on automatic machines, or a combination of both. Full design assistance is available on request, but a few points to think about are listed opposite.		Material Dimensions For flat strip we work up to about 3mm (0.116”) thick, in virtually any width and length. If possible, using standard thickness and widths can reduce costs considerably. Holes (size and position) Ensure the holes in the strip do not result in weakness. Diameters/Radii (on ends and corners) For circlips, specify the internal, or external, size the clip should fit into, or over. Bends (location and angles) Applicable to both wire and flat shapes.

MATERIAL SELECTION
 
We stock a large range of standard spring steels, stainless spring steels and various alloys such as Inconels and Nimonics. The choice of material depends primarily on the application, and the level of corrosion resistance required.

• Carbon Spring Steels
  Usually specified to BS5216, this range of materials offer exceptional spring properties but a low level of corrosion resistance. Springs would usually be supplied oil-coated.
  
• Stainless Spring Steels
  We stock two main variants of BS2056 material – 302S26 and 316S42. Both offer good corrosion resistance and are ideal for use in “clean” environments such as food preparation areas, or medical applications.
  
• Nickel Alloys
  We stock a complete range of Inconel X750, a spring alloy ideally suited for use in petrochemical and high-temperature applications, along with other specialist alloys such as Nimonic 90 and Hastelloy C276.

We also stock a large amount of less common materials including Beryllium Copper, Phosphor Bronze and Titanium. Please contact our design team for more information.

USEFUL CONVERSIONS

• Force:
  1kg  =  2.20462lb  =  9.80665N
  1lb  =  0.45359kg  =  4.44822N
  1N  =  0.22481lb  =  0.10197kg
  
• Length:                  Rate:
  1mm  =  0.03937in   1N/mm  =  5.7101lb/in
  1in  =  25.40mm      1lb/in  =  0.1751N/mm
  
• Stress:
  1N/mm²  =  145.03774lb/in²  =  1x106Pa
  1lb/in²  =  0.006894757N/mm²  =  6894.76Pa
  1Pa  =  0.00014503774lb/in²  =  1x10-6N/mm²

 

We are happy to work with either Imperial or metric measurements, or a combination of both. Please ensure units and tolerances are clearly stated if required

LEFT & RIGHT HAND
 
Often, the direction a spring is wound is unimportant – but in some cases it is crucial. The diagrams below indicate the two “hands” –  a right-hand spring will screw onto an ordinary thread:

Left-hand Wound	Right-hand Wound

COUNTING COILS
 
If you are going to specify the dimensions of a spring, it is crucial that the number of coils is counted correctly, as this can have a huge effect on the strength of the spring.

It is actually very straightforward, simply start at one end of the spring, where the wire has been cut, then follow the wire round – every time you go through 360º that counts as a full coil (180º = ½ coil; 90º = ¼ coil etc.) The compression spring pictured right has FIVE total coils (not six). The same method applies to extension springs and torsion springs.

1. How do you figure out how many active coils a spring has?
In any spring, some portion of the end coils will probably be inactive. The number of inactive coils
varies depending on the spring end configuration and mating component geometry. The following equations
give approximate active coil counts, assuming that the springs are compressed between parallel plates.

For closed ends (ground or unground): Na ??Nt – 2
For open ground ends: Na ??Nt – 1
For open unground ends: Na ??Nt

In practice, the number of inactive coils varies slightly as a spring is compressed. If the spring output at two
operating heights is known, the number of active coils over the operating height range can be calculated
using the following equation for any end configuration.

           Gd4 ( h1 – h2 )
Na =  --------------------
8 (OD – d)3 (P2 – P1)

G = shear modulus of the spring material
d = wire diameter
OD = spring outside diameter
h1, h2 = spring operating heights
P1, P2 = spring force at heights h1 and h2, respectively.

2. What is the difference between closed and closed ground ends?
Springs can be coiled with a variety of end configurations. If the space between the coils is reduced to the point where the wire at the tip makes contact with the next coil, the end is said to be “closed”. If there is no reduction in pitch at the end coils, the end is referred to as “open”. Between these two extremes is an end type known as “semi-closed” in which the space between coils is reduced, but there is a gap between the tip and next coil. The most common configuration in industrial springs is closed ends.
An additional grinding operation may be applied to any of the end configurations listed above. Grinding removes material for the spring end coils to create a flat surface perpendicular to the spring axis. This may be done for a variety of reasons including more even distribution of the spring force to the working assembly and improved ease of assembly since the spring is more likely to stand upright unassisted (particularly with smaller index springs).
Springs can be manufactured with any of the ascoiled configurations listed below. Any of these configurations can be provided either in the ground or unground condition.
Stock springs are listed in the catalog with specific ends (C = Closed, CG = Closed & Ground or O = Open). If you need a different type of end than what is listed, we can custom manufacture for you (see page 358 for Custom Springs).
The figure below shows schematics of both open and closed ends in both the ground and unground conditions.

3. What is a safe design stress for a compression spring?
This question does not have a single, simple answer. The answer depends heavily on the type of material used (e.g. music wire, stainless steel, chrome-silicon, etc.), material grade (e.g. commercial vs. valve spring quality, standard or high strength, etc.) and the service environment (e.g., static vs. cyclic, corrosive atmosphere, extremely high or low temperatures, etc.).
A spring that has infinite fatigue life under low deflection conditions may take a set if compressed to solid height. Another spring optimized for static life in sea water may have very poor fatigue life when cycled in air.
The design process typically begins with selecting a material type appropriate for the application environment. For static conditions, the spring designer will generally select a stress level appropriate for the selected material that will assure stable spring force output over time. For cyclic conditions, not only does the force output over time have to be stable, but the spring must be able to survive the intended life without breaking. Finally, manufacturability limitations can also restrict design stress levels.
The best recommendation here is to understand what is desired from the spring in service and work with a Century Spring design engineer to develop the optimum design for the operating conditions. Knowing the answers to the following questions will greatly assist the spring designer.
• Will the spring operate under static or cyclic conditions? If cyclic, what are the minimum and maximum operating loads, deflections, or heights? What is the desired life?
• What is the operating environment?
• What is the operating temperature?
• Does the assembly include physical stops to limit spring deflection? If so, what are the limits?
4. Which material gives the best corrosion resistance?
Once again, the actual operating environment plays a significant role. Many coatings are available that can provide adequate corrosion resistance for wire types that would not themselves resist corrosion. These
include powder coating, phosphating with an oil dip or spray, and plating in some cases. Generally speaking,
a coated spring produced from a traditional spring material will involve less cost than producing a spring from stainless steel.
When the application is such that coated spring wire will not meet the requirements of the application, the focus turns to stainless steel wire. Type 302 stainless steel is generally the first choice. This wire can yield very corrosion-resistant springs for most environments. When the application calls for high operating temperatures as well, 17-7 PH wire will also likely be considered.
5. How do you calculate rate/loads for disc spring stacks?
The effective spring rate of a stack of spring washers depends on the orientation of the stack. If Belleville spring washers are stacked so that they nest together (i.e. stacked like paper cups), they are said to be in
“series” with each other. When a stack of springs in series is deflected, all of the springs in the stack deflect as much as the total stack deflection. The effective spring rate for spring washers in series is simply the sum of the individual spring washer rates.
This is an effective way of achieving very high force output in very limited operating space. For a stack of n spring washers in series, the effective spring rate is calculated using the following equation. If spring washers are stacked such that they meet OD-to-OD and ID-to-ID, the stack is said to be in “parallel”. In this case, the deflection of the stack is distributed between all of the springs in the stack.
The effective spring rate for the stack is lower than the softest individual spring rate in the stack. This is an effective means of gaining available deflection in limited operating space. For a stack of n spring washers in parallel, the effective spring rate is calculated using the following equation.
5. How do you calculate rate/loads for disc spring stacks? (continued from previous page)
In cases where spring washers are stacked in a combination of series and parallel, calculate the effective rates for segments of the stack in series and then calculate the entire stack as a parallel stack considering the series segments as single springs with their respective effective spring rates.
6. What is free length?
For a compression spring, it is the length of the spring from one end to the other when no load is applied.
For a tension spring, it is the length between the inside diameter of the two end hooks when no load is applied.
7. How long will a compression spring last?
The effective life of a compression spring depends heavily on the operating environment. A spring designed for a static application with a properly chosen material should last indefinitely. In cyclic applications, springs are generally designed for infinite life; however, application nuances such as resonant vibration could drastically reduce spring life.
8. How do I know if a spring is RHW or LHW?
When looking along the axis of a spring, curl your index finger so that it follows the same direction as the wire from the spring body to the wire tip nearest you. If the end coil wraps in the same direction as your index finger (picture below) then it is that hand (right or left). See illustration below for method and a Right Hand Wound spring.
9. If I cut a spring in half, would the rate stay the same?
Cutting springs generally decreases the number of active coils. This forces an increase in spring rate. The spring rate is proportional to 1/Na, so reducing the number of active coils by half doubles the spring rate.
10. What material is best for high temperature applications?
As temperature resistance increases, the material and processing cost typically increases significantly. Therefore, it is usually wise to select a material that provides resistance for the intended temperature
range with minimal excess capability. The table below lists a variety of spring materials and their maximum
service temperatures.
Wire Type Max Temp.
Music Wire 250°F
Hard Drawn Carbon 250°F
Oil Tempered Carbon 300°F
Chrome Vanadium 425°F
Chrome Silicon 475°F
Wire Type Max Temp.
302 Stainless 500°F
17-7 PH 600°F
NiCr A286 950°F
Inconel 600 700°F
Inconel X750 1100°F
11. If I stack two springs, would the rate stay the same?
Stacking springs definitely changes the spring rate. The effective spring rate of the stack will be less than the softest spring in the stack. The effective spring rate for a stack of n springs is calculated using the following equation.

keff =----------------1-----------------------
1/k1 + 1/k2 + 1/k3 • • • + 1/kn

12. Where can I find minimum tensile strength for materials?
Most spring materials are defined in ASTM specifications. In general, tensile strength varies with wire diameter. The specifications typically include a table that lists allowable tensile strength ranges for various wire diameter ranges. A list of popular material types and the corresponding ASTM specification is given below. As an alternate source, the Spring Manufacturers Institute publishes a Handbook ofSpring Design as well as an Encyclopedia of SpringDesign (see page 11), both of which include tensile strength data for a variety of spring materials.
Wire Type ASTM Spec
Oil Tempered Carbon (Commercial) A229
Oil Tempered Carbon (Valve) A230
Chrome-Silicon (Commercial) A401
Chrome-Silicon (Valve) A877
Chrome-Vanadium (Commercial) A231
Wire Type ASTM Spec
Chrome-Vanadium (Valve) A232
Hard Drawn Carbon A227, A764
High Tensile Hard Drawn Carbon A679
Music Wire A228
Stainless Steel A313
13. What is initial tension?
Initial tension is most often discussed as it relates to extension spring. Extension springs are usually manufactured in a manner that requires a certain amount of force be applied before any deflection is realized. This minimum force is referred to as “initial tension”. The load vs. deflection chart below shows the effect graphically. The load PI is required to overcome the spring’s initial tension. From that point, the spring force increases with deflection at the spring rate. See chart on next page.