Introduction to Ring Springs
I. Scope
This document specifies the definition, classification, design calculation, technical requirements, testing methods, inspection rules, marking, packaging, transportation, and storage of annular springs.
This document applies to the outer diameter ϕ18mm ~ ϕ500mmCircular Spring
Section II: Standard Reference Documents
The contents of the following documents are incorporated into this document as indispensable clauses through normative references within the text. For referenced documents with dates, only the version corresponding to that date applies to this document; for referenced documents without dates, the new version (including all amendments) applies to this document.
GB/T 230.1Metal Rockwell Hardness Test1Partial: Test Method
GB/T 1031Surface Roughness Parameters and Their Values
GB/T 1182Shape and Position Tolerances - General Rules, Definitions, Symbols, and Representation Methods
GB/T 1184-1996Form and Position Tolerance / Unspecified Tolerance Values
GB/T 1222Spring Steel
GB/T 1800.1Ultimate Fit & Clearance Basics1Partial: Vocabulary
GB/T 1800.2Limit and Fit Fundamentals2Basic Regulations on Tolerances, Deviations, and Fit
GB/T 1800.3Extreme and Fit Fundamentals3Partial: Standard Tolerance and Basic Deviation Values Table
GB/T 1800.4Ultimate and Fit Fundamentals4Partial: Standard Tolerance Grades and Limits of Deviation for Holes and Shafts
GB/T 1804-2000General Tolerance - Tolerance for linear and angular dimensions not specified.
GB/T 1805 Spring Terminology
GJB 2028Magnetic Particle Inspection
III. Terms and Definitions
GB/T 1805The terms and definitions defined herein and listed below apply to this document.
3.1Inner Ringinternal（inside）ring
Inner ring with external working cone faces on both ends
3.2Outer Ringexternal（outer）ring
Outer ring with internal working cone surfaces on both ends
3.3End Ringend ring
An inner ring with only one end featuring an external working cone surface, located at the ends of a circular spring.
4. Parameter Name, Symbol, and Unit
Table1The parameter names, symbols, and units apply to this document. For ease of use, a structural illustration is provided, as shown in Figure1As shown.
Table1 Parameter Name, Symbol, and Unit
Serial Number | Parameter Name | Symbol | Unit | Description |
1 | Spring Inner Diameter | D1 | mm | |
2 | Spring Outer Diameter | D2 | mm | |
3 | Inner Ring Outer Diameter | D1' | mm | |
4 | Outer Diameter Inside Ring | D2' | mm | |
5 | Initial working load | P1 | N | |
6 | Workload completed | P2 | N | |
7 | Spring Free Length | H0 | mm | |
8 | Starting Work Height | H1 | mm | |
9 | Job completion height | H2 | mm | |
10 | Ring thickness | h | mm | |
11 | Spring spacing after loading | S | mm | |
12 | Conical Half-Angle | β | ° | |
13 | Inner ring small cone diameter | d1 | mm | |
14 | Outer Ring Large Cone Diameter | d2 | mm | |
15 | Deformation amount | f | mm | |
16 | Load | F | N |
V. Technical Requirements
5.1Size
5.1.1The inner diameter, outer diameter, free height, and compression height of the circular spring should comply with the specifications in the product drawing.
5.1.2The inner and outer ring dimensions of the circular spring should conform to the tolerance and fit.GB/T 1800.1~GB/T 1800.4The relevant provisions state that the extreme deviations of dimensions not marked with tolerance should comply with...GB/T 1804-2000Please provide the Chinese content to be translated.mGraded specifications.
5.1.3The inner and outer rings of the annular spring should conform to the shape and position tolerances.GB/T 1182、GB/T1184~1996Or provisions regarding product drawings, where shape and position tolerances are not specified.GB/T 1184-1996Please provide the Chinese content that you would like to have translated into American English.kGrade specifications.
5.1.4The radial dimensions and tolerances of the inner and outer rings of the annular spring should comply with the table.2Regulations specify, the inner and outer rings' shapes are as depicted.2Shown.
Table2 Radial dimensions and tolerances
Outer Diameter Size | Inner Ring | Outer Ring | ||
D1 | D1' | D2 | D2' | |
ϕ18~ 500 | H9/H10 | h8/h9 | H8/H9 | h9/h10 |
Table3 Other sizes and tolerances
Diameter | Project | |||
H0 | h | δ | β | |
ϕ18~30 | -0.2 +0.2 | -0.1 +0.1 | -0.1 +0.1 | -0.1° ＋0.1° |
ϕ30~50 | -0.3 +0.3 | -0.1 +0.1 | -0.1 +0.1 | -0.1° ＋0.1° |
ϕ50~80 | -0.4 +0.4 | -0.2 +0.2 | -0.2 +0.2 | -0.1° ＋0.1° |
ϕ80~120 | -0.6 +0.6 | -0.2 +0.2 | -0.2 +0.2 | -0.1° ＋0.1° |
ϕ120~00 | -0.8 +0.8 | -0.2 +0.2 | -0.2 +0.2 | -0.1° ＋0.1° |
ϕ200~300 | -1.2 +1.2 | -0.3 +0.3 | -0.3 +0.3 | -0.1° ＋0.1° |
ϕ300~500 | -1.5 +1.5 | -0.3 +0.3 | -0.3 +0.3 | -0.1° ＋0.1° |
5.2Materials
The materials for the inner and outer rings of the circular spring should comply with:GB/T 1222The provisions of relevant technical agreements shall be included, and the quality certificate must be attached. The material can only be put into use after being re-inspected and confirmed as qualified by the manufacturer. The surface of the material should be smooth with no visible scratches, dents, or other defects. If other materials are required, it shall be agreed upon by both the supplier and the buyer.
5.3Process
Large-scale production of annular springs, with the inner and outer rings being blanks forged and then rolled into finished shape and size on a transfer ring mill, followed by heat treatment after inspection and qualification.
Ring springs produced in small quantities, with blanks forged freely and then machined to achieve the finished shape and dimensions, followed by heat treatment. Contact surfaces are ground if necessary after heat treatment.
The inner and outer ring surfaces of the circular spring should meet the roughness requirements.GB/T 1031Regulations regarding the product's pattern or specifications, the surface roughness of the inner and outer ring conical surfaces is generally:Ra0.4~Ra0.8。
Due to the thin ring thickness, special attention should be paid during manufacturing to avoid distortion in the ring.
5.4Appearance quality
The inner and outer rings of the annular spring should have smooth arcs and cylindrical surfaces, as well as flat ends, without any damage, warping, burrs, or fractures.
5.5Internal Quality
The inner and outer rings of the circular spring should not have cracks or blow holes, etc., as internal defects.
5.6Design and Structure
5.6.1The design of the annular spring should consider the requirements for stiffness, strength, and motion stability, and should meet the smoothness of motion for the entire caching system and adapt to its working environment.
5.6.2The structure of the annular spring should meet the basic requirements that there is no sticking phenomenon between the inner and outer rings under lubrication conditions.
5.6.3The annular spring is guided by the inner guide rod, and the single side should not exceed...D1 ×2%Retain the gap between the retaining ring spring and the guide rod; the retaining ring spring should be guided by the outer ring guide tube, with the single side not exceedingD2 ×2%Retain the gap between the retaining ring and guide tube.
5.6.4Typical design characteristic curve of a circular spring within a loading and unloading cycleOABOAs shown3As shown.OAThe section indicates that the compression of the circular spring during loading is proportional to the load.ABThe section indicates that the compression amount during the initial unloading stage should remain relatively constant and exhibit a distinct lagging characteristic.BOThe section indicates that as the load is reduced to a certain degree, the compression begins to decrease and continues to decrease to zero during the unloading process. At this point, the annular spring starts to extend and should return to its original size.
5.6.5The annular spring should possess well-designed damping properties, and the total energy loss upon deformation and recovery should generally not be less than50%。
5.6.6Internal and external ring hardness
The inner and outer rings of the circular spring, after heat treatment, should generally have a surface hardness value of:48HRC-54HRC。
5.6.7Surface Treatment
The inner and outer rings of the circular spring should be treated for rust prevention in accordance with relevant standards after mechanical processing, such as phosphatizing and oxidizing.
5.6.8High-pressure treatment
Circular springs should be subjected to high-pressure treatment; unless otherwise specified, the general duration for high-pressure treatment should not be less than24h。
5.6.9Wear-in treatment
Circular springs should be磨合processed according to the product drawing specifications. When the drawing does not specify the number of磨合processing cycles, the general number of磨合processing cycles should not be less than10Next.
5.6.10Workload
Circular springs, after being subjected to high-pressure and磨合 treatment, are capable of withstanding working loads(P1OrP2The value should conform to the specifications of the product drawing or the contract.
5.6.11Adhesion Rate
The fit rate between the inner and outer rings of the annular spring corresponding to the conical contact surface should not be less than75%。
5.6.12Service Life
The service life of the circular spring should comply with the specifications of the product drawings and the manufacturing acceptance technical requirements.
Section 6: Inspection Regulations
6.1Inspection Conditions
Except as otherwise specified, the following conditions shall apply:
aIndoor Inspection: Temperature5℃ ~ 35 ℃Relative humidity not exceeding80%；
bOutdoor Inspection: When using equipment, it should meet the environmental requirements permitted by the equipment.
6.2First Article Inspection
6.2.1The first piece identification inspection items for annular springs should be in accordance with the product drawing, contract, and the table below.4Regulations.
6.2.2The inspected samples for the first article inspection should not be fewer than two pieces.
6.2.3If all inspected samples and all items meet the requirements of this specification, the initial inspection is deemed to pass; if any inspected sample or any inspection item of the initial inspection does not meet the requirements of this specification, the initial inspection is deemed to fail.
Table4 Inspection Item List
Serial Number | Inspection Items | Requirements Article Number | Inspection Method Article Number | First Article Inspection | Quality Consistency Inspection | ||
A | B | C | |||||
1 | Dimensions | 5.1 | 6.4.1 | ● | ● | - | - |
2 | Appearance quality, surface treatment | 5.2、5.5.7 | 6.4.2 | ● | ● | - | - |
3 | Internal Quality | 5.3 | 6.4.3 | ● | ● | - | - |
4 | Inner and outer ring hardness | 5.5.6 | 6.4.4 | ● | ● | - | - |
5 | High-pressure treatment | 5.5.8 | 6.4.5 | ● | ● | - | - |
6 | Machine Break-in | 5.5.9 | 6.4.6 | ● | ● | - | - |
7 | Workload | 5.5.10 | 6.4.7 | ● | ● | - | - |
8 | Tightness rate | 5.5.11 | 6.4.8 | ● | - | ○ | - |
9 | Service Life | 5.5.12 | 6.4.9 | ○ | - | - | ○ |
Note:●Mandatory inspection items○Inspect according to product drawings or items specified in the contract.-Uninspected Item | |||||||
6.3Quality Consistency Inspection
6.3.1Sampling Plan, Batching Rules
Circular springs shall be inspected in batches, with each batch consisting of inner and outer rings made from the same specification and brand of steel, produced under the same processing conditions. The batch quantity for inspection shall be as specified in the product drawings or contract.
AAll items in the group inspection are subject to full inspection procedures.BGroupCInspection items are conducted according to the product drawings or the sampling scheme specified in the contract.
6.3.2Qualification Criteria
AAll items inspected by the group meet the requirements specified in this specification.AGroup inspection passed; ifAAny inspection item in the group inspection that does not meet the requirements specified in this specification is deemed non-compliant.AGroup inspection failed.
Convicted ofADefective items that have been repaired can be re-inspected, and non-compliant products should be removed.
If a single-loop part breaks during the high-pressure treatment inspection, the quantity shall not exceed the batch of single-loop parts submitted for inspection.3At %, replacement with internally or externally processed rings post high-pressure treatment is permitted; re-subject to high-pressure treatment inspection. If the number of broken individual rings exceeds the above specification, the batch should undergo double the required high-pressure treatment inspection time. During the re-high-pressure treatment inspection, if another individual ring breaks, the batch is deemed不合格.ALot inspection failed.
BIf any sample in the group inspection does not meet the requirements specified in this specification, double the number of samples should be re-inspected. If there is still a sample that does not meet the requirements, the batch is deemed不合格.BLot inspection failed.
Be deemedBBatches with group inspection failures can undergo full inspection and remove the non-compliant items.
CIf any sample in the group inspection does not meet the requirements specified in this specification, double the quantity should be re-inspected. If there is still a sample that does not meet the requirements, the batch is deemed不合格.CGroup inspection failed.
6.4Inspection Method
6.4.1Dimensions
Inspection using general or interchangeable measuring tools that have been calibrated, with the measuring tools for inner or outer diameter having a least count value not less than0.05mm。
6.4.2Appearance quality, surface treatment
Inspect the appearance quality and surface treatment by visual and tactile methods, or by referencing standard samples; use as a dispute resolution method when needed.5Magnify with a 10x loupe for inspection.
6.4.3Internal Quality
Please provide the Chinese content to be translated.GJB 2028Inspected in accordance with the regulations.
6.4.4Inner and outer ring hardness
Please provide the Chinese content that needs to be translated into American English.GB/T 230.1Inspect in accordance with the specified regulations.
6.4.5High-pressure treatment
The annular spring is subjected to high-pressure treatment on a pressure testing machine, compressing it until the coils are in contact with no significant gaps, or to the specified height for the corresponding product, or to the load specified for the corresponding product, while maintaining the specified duration of action. After the high-pressure treatment, inspect the appearance quality visually.
6.4.6Machining and Finishing
The磨合treatment is conducted after the strong pressure treatment has been approved.
On the磨合试验机， maintain the annular spring in a compressed state, and have itH1Please provide the Chinese content you would like translated into American English.H2Round-trip operations, with the number of round trips as per3.9.2The process should not be interrupted and should be completed in one continuous session.
6.4.7Workload
The measurement of workload should be conducted after the磨合 process has been qualified.
On the pressure testing machine, compress the circular spring toH1OrH2Measure and record the work loadP1OrP2。
If the work load does not conform to the product drawings or contract specifications, adjustable washers can be used for adjustment. The thickness and number of the washers should comply with the requirements of the product technical specifications.
6.4.8Adhesion rate
Tested by coal tar method.
6.4.9Service Life
Conduct fatigue tests on the circular spring, ensuring the stroke matches the actual working stroke, the reciprocating frequency is the same as the working frequency, and the operating times should not be less than the actual working life times.110%~130%Inspect or check the working load, internal quality, and appearance quality of the annular spring after fatigue testing, ensuring they meet the requirements of the corresponding product drawings and this specification, and record the findings.
Section 7: Branding, Packaging, Transportation, and Storage
7.1Brand
7.1.1At a prominent location on the circular spring, there should be a clear, legible durability mark.
7.1.2The logo should include the following content:
a) Product Model
b) Product Trademark
c) Manufacturer's name or code;
d) Manufacturing Date (Year, Month).
7.1.3Products that pass the factory inspection should have a certificate of conformity or a conformity mark.
7.1.4Certificate of Conformity includes:1Product Name, Model, Specifications;2Product Number:3Factory Name or Code；4Year of manufacture, month;5Inspection personnel.
7.2Packaging
7.2.1Product packaging and transportation labels should meet customer requirements.
7.2.2Packaging should ensure that it is not crushed or deformed.
7.2.3The packaging box should display product name, quantity, and protective markings.
7.2.4The packaging box should indicate the stacking direction and the number of layers allowed to be stacked.
7.2.5The packaging box should include a product certification and a product manual.
7.3Transportation and Storage
7.3.1Circular springs should be stored in an upright position during transportation and storage, with the packaging box not lying flat and no damage to the packaging.
7.3.2Circular springs should be handled to avoid impacts during transportation and storage. They should be kept away from acids, alkalis, salts, oils, water, soot, and other organic solvents, and should be as far away from heat sources as possible.
A.1Standard Ring Spring Size Series is listed in the table.A.1
TableA.1
D2 | D1 | h | t | δ0 | β | F | Gea |
mm | mm | mm | mm | mm | ° | kN | kg |
18.1 | 14.4 | 3.6 | 4.4 | 0.8 | 13.1 | 5 | 0.002 |
25 | 20.8 | 5 | 6.2 | 1.2 | 13.5 | 9 | 0.004 |
32 | 27 | 6.4 | 8 | 1.6 | 13.4 | 14 | 0.007 |
38 | 31.7 | 6.4 | 9.4 | 1.8 | 13.4 | 20 | 0.012 |
42.2 | 34.6 | 8.4 | 10.4 | 2 | 13.2 | 26 | 0.018 |
48.2 | 39.4 | 9.6 | 11.8 | 2.2 | 13.4 | 34 | 0.026 |
55 | 46 | 11 | 13.6 | 2.6 | 13.2 | 40 | 0.035 |
63 | 51.9 | 12.6 | 15.4 | 2.8 | 13.3 | 54 | 0.056 |
70 | 58.2 | 14 | 17.2 | 3.2 | 13.2 | 65 | 0.074 |
80 | 67 | 16 | 19.6 | 3.6 | 13.5 | 83 | 0.105 |
90 | 75.5 | 18 | 22 | 4 | 13.3 | 100 | 0.145 |
100 | 84 | 20 | 24.4 | 4.4 | 13.5 | 125 | 0.203 |
130 | 111.5 | 24.8 | 30 | 5.2 | 13.4 | 160 | 0.376 |
124 | 102 | 24.8 | 30 | 5.2 | 13.3 | 200 | 0.408 |
140 | 116 | 28 | 34 | 6 | 13.3 | 250 | 0.568 |
300 | 250 | 60 | 77 | 11.6 | 13.2 | 1000 | 5.51 |
320 | 263 | 64 | 76.4 | 12.4 | 13.1 | 1200 | 7.06 |
350 | 288 | 70 | 83.2 | 13.2 | 13.2 | 1400 | 9.18 |
400 | 330 | 80 | 95.2 | 15.2 | 13.1 | 1800 | 13.56 |
aWeight of the circular spring corresponding to a pair of contact faces | |||||||
B.1Ring Spring Design Parameters Selection
（1） Cone Surface Inclination - When cone surface inclinationβWhen selected smaller, the spring stiffness is lower. Ifβ <ρAn automatic locking will occur upon disassembly, meaning it cannot be retracted.βAngle selection too large, the load during elastic deformation recoveryPRLarger, reducing the shock-absorbing capability of the annular spring. During design, it is advisable to...β=12°~20°When the precision of the conical surface machining is high, it can be takenβ=12°Generally, when the processing accuracy is moderate, often takenβ=14.04°Poor lubrication conditions, with a higher coefficient of friction.βSize should be larger to prevent self-locking.
（2） Friction FactorfμWith friction angleρSelect as per the following conditions:
Raw surface under heavy-duty working conditions | ρ ≈9° | fμ ≈ 0.16 |
Precision-machined surface under heavy-duty working conditions | ρ ≈ 8.5° | fμ ≈ 0.15 |
Precision machined surface under heavy-duty working conditions | ρ ≈ 7° | fμ ≈ 0.12 |
（3） Allowable stress of circular springs as shown in the tableB.1。
TableB.1Allowable stress of commonly used materials for annular springs/MPa
Processing and Usage Conditions | Outer Ring Allowable Stressσ1p | Permitted stress in inner ringσ2p |
For general lifespan requirements | 900 | 1200 |
For short life expectancy requirements (unprocessed surface) | 1000 | 1300 |
For short life expectancy requirements (finish-processed surfaces) | 1200 | 1500 |
