This standard specifies the technical requirements, test methods and inspection rules for high temperature resistant circular cross-section cylindrical spiral compression springs. JB/T 6655-1993 High temperature resistant spring technical conditions JB/T6655-1993 Standard download and decompression password: www.bzxz.net

Machinery Industry Standard of the People's Republic of China
Technical Conditions for High Temperature Resistant Spring
1 Subject Content and Scope of Application
JB/T 6655--- 93
This standard specifies the Technical requirements, test methods and inspection rules for high-temperature circular cross-section cylindrical spiral compression springs. This standard is applicable to cold-rolled and hot-rolled circular cross-section cylindrical spiral compression springs (hereinafter referred to as springs) with an operating temperature above 300°C. The material cross-section diameter of the spring Greater than or equal to 0.5mm. 2 Reference standards
Method for determination of decarburized layer depth of steel
GB224
GB230
GB231
GB1220
GB1222||tt| |Metal Rockwell hardness test method
Metal Brinell hardness test method
Stainless steel rod
Spring steel
GB 1239.2
Cold rolled cylindrical spiral compression spring Technical conditions Hot rolled cylindrical coil spring Technical conditions
GB 1239.4
GB1239.5
GB1299
GB1805
Sampling inspection of cylindrical coil spring||tt| |Alloy tool steel technical conditions
Spring terminology
GB4459.4
GB9943
Mechanical drawing
Spring drawing method
High speed tool steel Rod technical conditions
GBn175 high alloy
3 product classification
Spring structure type classification is shown in Table 1.
Code name
YI
RY1
简
金
A
Ministry of Machinery Industry of the People's Republic of China 1993-05 -07 Approved end structure type
The rings at both ends are tightly connected and smooth
Implemented on 1994-01-01
583
Code name
YI| |tt||YI
RY
4 Technical requirements
Simplified
Picture
JB/T6655---93
Continued table 1
End structure type
The rings at both ends are tightly connected and not worn
A0
The rings at both ends are not tightly tightened
The rings at both ends are tightly connected , no grinding or smoothing
4.1 Products should comply with the requirements of this standard and be manufactured in accordance with product drawings and technical documents approved through prescribed procedures. 4.2 Permanent deformation
After the finished spring is compressed three times under the test load, its permanent deformation shall not exceed the drawing requirements. 4.3 Spring characteristics and limit deviation
4.3.1 Spring characteristics
Spring characteristics It should comply with the provisions of Article 4.3.1 or 4.3.1.2. If there are special needs, it should also comply with the provisions of Article 4.3.1.3. 4.3.1.1 Under the load of the specified height, the deformation of the spring should be 20% of the deformation under the test load. ~~80%, when level 1 accuracy is required, the deformation of the spring under a specified height load should be more than 4mm. Test load P. : When measuring spring characteristics, the maximum load allowed on the spring is used as the test load. Test stress: When measuring spring characteristics, the maximum load-bearing stress allowed on the spring is used as the test stress. 4.3.1.2 At the specified load height, the spring deformation should be between 20% and 80% of the deformation under the test load. 4.3.1.3 When the spring stiffness is specially required, its deformation should be between 30% and 70% of the deformation under the test load. 4.3.2 The limit deviation of spring characteristics
4.3.2.1 The limit deviation of spring load is as specified in Table 2. Table 2
Limit deviation accuracy level
Number of effective turns
≥3～10
>10
58.4
1||tt ||10.05P
二0.04P
-0.101www.bzxz.net
±0.08P
N
JB/T 6655-93
4.3 .3 The limit deviation of spring characteristics can be used symmetrically according to the agreement between the supplier and the buyer, and its tolerance remains unchanged. 4.4 Limit deviation
4.4.1 The outer diameter or inner diameter of the spring
The limit of the outer diameter or inner diameter of the cold rolled spring The deviation is as specified in Table 3, Table 3
limit deviation accuracy level
winding c(Drar-
48
>8~~15
> 15～22
-
±0.01, minimum 0.15
±0.015D, minimum ±0.2
+0.02D, minimum +0.3
hot coil The limit deviation of the outer diameter or inner diameter of the spring is as specified in Table 4. Table 4
from
4.4.2
free height
|tt||Degree
250
250~-500
e500
He
2
+0.15), minimum|| tt||0.02 minimum
t.
±0.03D, minimum ±0.5
limit
bias
±0.01.minimum +1.|| tt | When springs have characteristic requirements, the free height is used as a reference. Table 5
Limit deviation
One accuracy level
cD
Spiral
4℃8
>8~15||tt| |≥15～22
±0.01H. Minimum ±0.2
+0.015H Minimum ±0.5
±0.02H. Min ±0.6
2
±0.02H min +0.5
±0.03Ha, min ±0.7
+0.04H min ±0.8
mm| |tt||mm
mm
The limit deviation of the free height of the thermal coil is ±1.5% of the free height. When springs have characteristic requirements, the free height is used as a reference. 4.4.3 Verticality
The verticality of the axis line of the spring to both end surfaces is as specified in Table 6. Table 6
Accuracy level
Verticality
0.02H.
Note: (I)Y! , Y-type spring, verticality is not assessed. ②When the height-to-diameter ratio is >5 to 10, generally the spring is only required to be upright. 4.4.4 Pitch Uniformity
When compression springs with equal pitches are compressed to 80% of the total deformation, their normal pitch rings must not contact. 4.4.5 Pressure height
0.04H
The pressure height of the spring is not specified in principle. When the pressure height is required to be specified, the value calculated according to formula (1) shall be used as the maximum value. Hh-= nd mu
in; Hb——compression height;
-total number of pictures;
mm
(1)
588| |tt||dmr
JB/T 6655 -- 93
The maximum diameter of the material, its value is the sum of the maximum value of the material diameter and its limit deviation. 4.4.6. End face grinding
The ground part of the spring support ring with both ends of the rings tightly and ground flat is greater than or equal to 3/4 turns. The surface roughness requirement is 12%, and the end thickness is not less than Question about (1/8～1/4)d of material diameter. 4.5 Appearance
The surface of the spring should be smooth, without harmful defects visible to the naked eye, and harmful burn scars, cracks, oxidation, decarburization and other defects are not allowed.
4.6 Materials
4.6.1. Spring materials are recommended to use the grades specified in Table 7. surface?
Steel
Species
Heat-resistant spring steel
(GR1222)
Tool steel
(GB9943)
( GB1299)
Stainless steel
(GB1220)
High temperature alloy
(GBn175)
Brand
60Si2CrVA
65Si2MnWA| |tt||30W4Cr2VA
W6M05CriV2
W18Cr4V
3Cr2W8V
OCr17Ni7Al
1Cr18Ni9Ti
0Cr15Ni7M02Al
0Cr17Ni25Ti2MoVH||tt ||(GH2132)
No.
0Cr15Ni35W2Mo2Ti2A12B
(GB2135)
NiCr19Fe18Nb5Mo3TiB
(GH 4169)
NiCr15Fe7NbTi2Al||tt| |(GH4145)
Recommended maximum operating temperature C
350
350
500
450
500
500
350
400
430
550
600
600
600
4.6.2 Spring materials must have an inspection quality certificate from the material manufacturer and must be re-inspected by the spring manufacturer before they can be used. 4.7 Heat treatment
4.7.1 After the hot-rolled spring is formed, it must be uniformly heat treated, that is, quenching and tempering. 4.7.2 After the spring is cold-rolled with hard materials, it is stress-relieved and tempered. Its hardness will not change. be assessed. For cold rolled springs that need to be quenched and tempered, the number of quenchings must not exceed two times, and the number of temperings is not limited. 4.8 Hardness and decarburization
4.8.1 Hardness
The hardness after spring fire tempering is 45~55HRC. 4.8.2 Decarburization
The depth of the unilateral decarburization layer (ferrite transition layer) of the spring that has been quenched and tempered is allowed to be increased by 0.2 of the material diameter to the depth of the decarburization layer specified in the raw material standard. %.
4.9 Hot and pressure treatment
586
JB/T 6655—93
The spring must be hot and pressure treated according to the technical requirements of the drawing. 4.10 Surface treatment
The surface of the spring should be cleaned before anti-rust treatment. 4.11 Other requirements
Subject to agreement between the supplier and the buyer as needed. Inspection and test methods
Thermal relaxation test
5.1
Thermal relaxation test shall be agreed upon by both parties.
5.2 Other inspection and test methods shall be carried out in accordance with the provisions of GB1239.2 and GB1239.4. 6 Inspection rules
According to the provisions of Chapter 6 of GB1239.2.
Marking, packaging, transportation and storage
According to the provisions of Chapter 7 of GB1239.2.
Additional notes:
This standard is proposed and managed by the Machinery Standards Research Institute of the Ministry of Machinery Industry. This standard is drafted by Wuhan Spring Research Institute. The main drafters of this standard are Wan Guixiang, Li Yaqing, Zhang Yinghui, Yu Fang, and Wan Xuehong. 587
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