(!)Due to Microsoft's end of support for Internet Explorer 11 on 15/06/2022, this site does not support the recommended environment.
Instead, please kindly use other browsers like Google Chrome, Microsoft Edge or Mozilla Firefox.

7 Million Products, 2,000 Brands.
50,000 Stock items for Same Day Ship Out.

All Categories

Search by Application

inCAD Library

Brands

Brand List

Webcode Seach | Series: #CODE

Keyword suggestions

Part number suggestions

Discontinued Products

Please Note our New Address (effective April 1, 2024): 331 North Bridge Rd, #05-01 Odeon 331, Singapore 188720.

How can we improve?

How can we improve?

Feedback

Name (Optional)

E-mail Address (Optional)

Tel (Optional)

Thank you for your time.
Your feedback is essential for our continuous improvement
Privacy Policy

Thank you for your cooperation.

Thank you for your time.
Your feedback is essential for our continuous improvement
Please use the inquiry form.

Privacy Policy

Tension Springs/Configurable Length

MISUMI

Outer diameter size (Φ7, Φ11, Φ13, Φ15, Φ17) standard added!
A tension spring whose free length can be specified in units of 1 mm.
The outer diameter and length can be freely specified according to the intended use.
Piano wire is also based on the outer diameter.

(i)Caution

Please check the content on our website as the PDF does not contain the most up-to-date information.

Part Number

Configured Part Number is shown.

Type	Material
WFSP	SWP-A
UFSP	SUS304-WPB

Type	Material
BWFSP	SWP-A
BUFSP	SUS304-WPB

Specifications

Part Number	-	d	-	S
WFSP3 UFSP20	- -	0.3 2.6	- -	10 498

[ ! ]Maximum deflection factor is a numerical value for static loads.
When applying a dynamic load, use the maximum deflection factor × 0.65.
[ ! ]For the maximum deflection, the Web specifications show a percentage, and the catalog PDF shows the value when the S dimension is 50.
Both values give the same result when used.
[ ! ]For the standard spring constant, the Web specifications show a value where the S dimension is 10, and the catalog PDF shows the value when the S dimension is 50.

Part Number		Wire Dia. d mm	S 1mm Increment	Maximum deflection factor (S) ％		Standard Spring Constant (When S = 10) N/mm		Initial Tension N


Type	D			WFSP	UFSP	WFSP	UFSP	WFSP	UFSP
Type	D			BWFSP	BUFSP	BWFSP	BUFSP	BWFSP	BUFSP
WFSP UFSP BWFSP BUFSP	3	0.3	10〜300	176%	174%	0.13	0.11	0.18	0.21
	3	0.4		82%	84%	0.60	0.50	0.53	0.64
	4	0.4		172%	174%	0.20	0.20	0.31	0.38
	4	0.5		96%	92%	0.75	0.65	0.77	0.92
	5	0.5	10〜500	168%	164%	0.35	0.30	0.49	0.59
	5	0.6		100%	102%	0.90	0.80	1.01	1.21
	6	0.6		158%	164%	0.50	0.45	0.71	0.85
	6	0.8		72%	72%	2.35	2.05	2.13	2.55
	7	0.7		140%	132%	0.65	0.60	0.96	1.15
	7	0.9		70%	64%	2.60	2.25	2.94	3.5
	8	0.8		148%	152%	0.90	0.80	1.26	1.51
	8	1		82%	84%	2.90	2.55	3.04	4.26
	9	1	10〜550	112%	114%	1.95	1.70	2.45	3.43
	9	1.2		66%	66%	5.25	4.65	4.41	6.17
	10	1		148%	140%	1.35	1.20	1.96	2.74
		1.2		88%	86%	3.65	3.25	4.31	6.03
		1.4		58%	56%	8.50	7.50	7.64	10.7
	11	1		160%	152%	1.00	0.85	1.45	2.01
		1.2		92%	90%	2.65	2.35	3.24	4.51
		1.4		62%	60%	6.20	5.40	6.39	8.87
	12	1		232%	226%	0.75	0.65	1.18	1.65
		1.2		142%	140%	1.95	1.75	2.84	3.98
		1.4		92%	92%	4.55	4.00	5.39	7.55
		1.6		62%	60%	9.40	8.30	8.72	12.21
	13	1		240%	234%	0.55	0.50	0.93	1.29
		1.2		144%	142%	1.55	1.35	2.17	3.01
		1.4		94%	94%	3.50	3.05	3.95	5.49
		1.6		64%	62%	7.10	6.20	7.75	10.76
	14	1.2		208%	192%	1.20	1.05	2.06	2.88
		1.4		138%	130%	2.70	2.40	3.82	5.35
		1.6		94%	90%	5.55	4.90	6.66	9.32
		1.8		68%	66%	10.50	9.30	10.6	14.84
	15	1.2		212%	196%	0.95	0.85	1.5	2.09
		1.4		140%	132%	2.15	1.90	3.03	4.21
		1.6		96%	92%	4.40	3.80	4.74	6.59
		1.8		70%	68%	8.45	7.35	9.25	12.85
	16	1.4		192%	182%	1.75	1.55	3.04	4.26
		1.6		132%	130%	3.55	3.15	5.1	7.14
		1.8		96%	94%	6.65	5.90	8.33	11.66
		2		68%	70%	11.85	10.50	12.6	17.64
	17	1.4		194%	184%	1.45	1.25	2.21	3.08
		1.6		134%	132%	2.90	2.50	4.03	5.6
		1.8		98%	96%	5.55	4.85	6.74	9.37
		2		70%	72%	9.90	8.65	10.9	15.13
	18	1.6		176%	174%	2.40	2.10	4.02	5.63
		1.8		128%	128%	4.50	4.00	6.47	9.06
		2		94%	96%	7.95	7.00	10	14
		2.3		62%	60%	17.00	15.05	18.7	26.18
	20	1.8		168%	156%	3.15	2.80	5.1	7.14
		2		122%	120%	5.55	4.95	7.94	11.12
		2.3		82%	80%	11.85	10.50	15.2	21.28
		2.6		58%	58%	23.20	20.50	23.6	33.04
	22	2		150%	148%	4.05	3.60	7.35	10.3
		2.3		106%	104%	8.60	7.60	11.8	16.5
		2.6		74%	74%	16.75	14.80	19.6	27.4
		2.9		54%	54%	30.45	26.95	33.3	46.6
	25	2.3		144%	144%	5.60	4.95	9.8	13.7
		2.6		100%	104%	10.85	9.60	15.7	22
		2.9		76%	72%	19.65	17.40	22.5	31.5
		3.2		56%	54%	33.75	29.85	34.3	48
	28	2.6		138%	128%	7.45	6.60	12.7	17.8
		2.9		102%	98%	13.45	11.90	17.6	24.6
		3.2		78%	74%	22.90	20.25	27.4	38.4
		3.5		62%	58%	37.45	33.10	39.2	54.9

■Accuracy Standards
• D Dimension Tolerance

D/d^*1	Tolerance
Less than 8	±1.5% of D dimension (Min. ±0.2mm)
8~20	±2% of D dimension (Min. ±0.3mm)

*1. D/d = Spring Index
• S Dimension Tolerance
When d≤0.5, ±2 x Wire Dia.
(Ex: When d=0.3, ±0.6)
When d≥0.6, ±Wire Dia.
(Ex: When d=1.0, ±1.0)

• Calculate the maximum deflection and spring constant using the following formula.
• Maximum deflection Maximum deflection (mm) = S × maximum deflection factor (%)	• Spring constant(reference value) Spring constant (N/mm) ＝ reference spring constant × 10/S

Example) Calculation of maximum deflection and spring constant of UFSP20-2.6-498

Maximum deflection(mm) = 498×58% = 288.84	Spring constant(N/mm) = 20.50 ×	10	= 0.41
		498

[ ! ]For the maximum deflection, the Web specifications show a percentage, and the catalog PDF shows the value when the S dimension is 50.
Both values give the same result when used.
[ ! ]For the standard spring constant, the Web specifications show a value where the S dimension is 10, and the catalog PDF shows the value when the S dimension is 50.

Part Number

CAD Data download and 3D preview are not available because the part number has not yet been determined.

*In order to open the CAD Data download and 3D preview screen, the part number must be fixed.
Please confirm the part number from "Specification / Dimension"on the left side, and then perform the CAD Data Download / 3D Preview operation.

CAD Download

: 30; 45; 60

Part Number
BWFSP3-0.3-[10-300/1]
BWFSP3-0.4-[10-300/1]
BWFSP4-0.4-[10-300/1]
BWFSP4-0.5-[10-300/1]
BWFSP5-0.5-[10-500/1]
BWFSP5-0.6-[10-500/1]
BWFSP6-0.6-[10-500/1]
BWFSP6-0.8-[10-500/1]
BWFSP7-0.7-[10-550/1]
BWFSP7-0.9-[10-550/1]
BWFSP8-0.8-[10-500/1]
BWFSP8-1.0-[10-500/1]
BWFSP9-1.0-[10-550/1]
BWFSP9-1.2-[10-550/1]
BWFSP10-1.0-[10-550/1]
BWFSP10-1.2-[10-550/1]
BWFSP10-1.4-[10-550/1]
BWFSP11-1.0-[10-550/1]
BWFSP11-1.2-[10-550/1]
BWFSP11-1.4-[10-550/1]
BWFSP12-1.0-[10-550/1]
BWFSP12-1.2-[10-550/1]
BWFSP12-1.4-[10-550/1]
BWFSP12-1.6-[10-550/1]
BWFSP13-1.0-[10-550/1]
BWFSP13-1.2-[10-550/1]
BWFSP13-1.4-[10-550/1]
BWFSP13-1.6-[10-550/1]
BWFSP14-1.2-[10-550/1]
BWFSP14-1.4-[10-550/1]
BWFSP14-1.6-[10-550/1]
BWFSP14-1.8-[10-550/1]
BWFSP15-1.2-[10-550/1]
BWFSP15-1.4-[10-550/1]
BWFSP15-1.6-[10-550/1]
BWFSP15-1.8-[10-550/1]
BWFSP16-1.4-[10-550/1]
BWFSP16-1.6-[10-550/1]
BWFSP16-1.8-[10-550/1]
BWFSP16-2.0-[10-550/1]
BWFSP17-1.4-[10-550/1]
BWFSP17-1.6-[10-550/1]
BWFSP17-1.8-[10-550/1]
BWFSP17-2.0-[10-550/1]
BWFSP18-1.6-[10-550/1]
BWFSP18-1.8-[10-550/1]
BWFSP18-2.0-[10-550/1]
BWFSP18-2.3-[10-550/1]
BWFSP20-1.8-[10-550/1]
BWFSP20-2.0-[10-550/1]
BWFSP20-2.3-[10-550/1]
BWFSP20-2.6-[10-550/1]
BWFSP22-2.0-[10-550/1]
BWFSP22-2.3-[10-550/1]
BWFSP22-2.6-[10-550/1]
BWFSP22-2.9-[10-550/1]
BWFSP25-2.3-[10-550/1]
BWFSP25-2.6-[10-550/1]
BWFSP25-2.9-[10-550/1]
BWFSP25-3.2-[10-550/1]

Standard Unit Price	Minimum order quantity	Days to Ship	RoHS	Material	Hook Opposing Angle	Outer Dia. D (Ø)	Initial Tension (N)	Standard Spring Constant (N/mm)	Wire Dia. (Ø)	S (mm)
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	3	0.18	0.13	0.3	10 ～ 300
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	3	0.53	0.6	0.4	10 ～ 300
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	4	0.31	0.2	0.4	10 ～ 300
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	4	0.77	0.75	0.5	10 ～ 300
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	5	0.49	0.35	0.5	10 ～ 500
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	5	1.01	0.9	0.6	10 ～ 500
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	6	0.71	0.5	0.6	10 ～ 500
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	6	2.13	2.35	0.8	10 ～ 500
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	7	0.96	0.65	0.7	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	7	2.94	2.6	0.9	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	8	1.26	0.9	0.8	10 ～ 500
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	8	3.04	2.9	1	10 ～ 500
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	9	2.45	1.95	1	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	9	4.41	5.25	1.2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	10	1.96	1.35	1	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	10	4.31	3.65	1.2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	10	7.64	8.5	1.4	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	11	1.45	1	1	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	11	3.24	2.65	1.2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	11	6.39	6.2	1.4	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	12	1.18	0.75	1	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	12	2.84	1.95	1.2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	12	5.39	4.55	1.4	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	12	8.72	9.4	1.6	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	13	0.93	0.55	1	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	13	2.17	1.55	1.2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	13	3.95	3.5	1.4	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	13	7.75	7.1	1.6	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	14	2.06	1.2	1.2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	14	3.82	2.7	1.4	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	14	6.66	5.55	1.6	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	14	10.6	10.5	1.8	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	15	1.50	0.95	1.2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	15	3.03	2.15	1.4	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	15	4.74	4.4	1.6	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	15	9.25	8.45	1.8	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	16	3.04	1.75	1.4	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	16	5.1	3.55	1.6	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	16	8.33	6.65	1.8	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	16	12.6	11.85	2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	17	2.21	1.45	1.4	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	17	4.03	2.9	1.6	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	17	6.74	5.55	1.8	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	17	10.90	9.9	2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	18	4.02	2.4	1.6	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	18	6.47	4.5	1.8	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	18	10.00	7.95	2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	18	18.7	17	2.3	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	20	5.1	3.15	1.8	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	20	7.94	5.55	2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	20	15.20	11.85	2.3	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	20	23.60	23.2	2.6	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	22	7.35	4.05	2	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	22	11.8	8.6	2.3	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	22	19.60	16.75	2.6	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	22	33.30	30.45	2.9	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	25	9.80	5.6	2.3	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	25	15.70	10.85	2.6	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	25	22.50	19.65	2.9	10 ～ 550
-	1 Piece(s)	6 Day(s) or more	10	SWP-A	90°	25	34.3	33.75	3.2	10 ～ 550

Basic Information

Type	Standard Type

Configure

128 Part Numbers

View Part Numbers

Configure Remaining Specifications

Completed

Specification/Dimensions

Hook Opposing Angle
- 90°
Clear
Outer Dia. D(Ø)
3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

20

22

25

28
Clear
Initial Tension(N)
0.18

0.21

0.31

0.38

0.49

0.53

0.59

0.64

0.71

0.77

0.85

0.92

0.93

0.96

1.01

1.15

1.18

1.21

1.26

1.29

1.45

1.50

1.51

1.65

1.96

2.01

2.06

2.09

2.13

2.17

2.21

2.45

2.55

2.74

2.84

2.88

2.94

3.01

3.03

3.04

3.08

3.24

3.43

3.50

3.82

3.95

3.98

4.02

4.03

4.21

4.26

4.31

4.41

4.51

4.74

5.1

5.35

5.39

5.49

5.60

5.63

6.03

6.17

6.39

6.47

6.59

6.66

6.74

7.14

7.35

7.55

7.64

7.75

7.94

8.33

8.72

8.87

9.06

9.25

9.32

9.37

9.80

10.00

10.3

10.6

10.70

10.76

10.90

11.12

11.66

11.8

12.21

12.6

12.70

12.85

13.70

14

14.84

15.13

15.20

15.70

16.5

17.60

17.64

17.80

18.7

19.60

21.28

22.00

22.50

23.60

24.6

26.18

27.4

31.50

33.04

33.30

34.3

38.40

39.20

46.6

48.00

54.90
Clear
Standard Spring Constant(N/mm)
0.11

0.13

0.2

0.3

0.35

0.45

0.5

0.55

0.6

0.65

0.75

0.8

0.85

0.9

0.95

1

1.05

1.2

1.25

1.35

1.45

1.55

1.7

1.75

1.9

1.95

2.05

2.1

2.15

2.25

2.35

2.4

2.5

2.55

2.6

2.65

2.7

2.8

2.9

3.05

3.15

3.25

3.5

3.55

3.6

3.65

3.8

4

4.05

4.4

4.5

4.55

4.65

4.85

4.9

4.95

5.25

5.4

5.55

5.6

5.9

6.2

6.6

6.65

7

7.1

7.35

7.45

7.5

7.6

7.95

8.3

8.45

8.5

8.6

8.65

9.3

9.4

9.6

9.9

10.5

10.85

11.85

11.9

13.45

14.8

15.05

16.75

17

17.4

19.65

20.25

20.5

22.9

23.2

26.95

29.85

30.45

33.1

33.75

37.45
Clear
Wire Dia.(Ø)
0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1.2

1.4

1.6

1.8

2

2.3

2.6

2.9

3.2

3.5
Clear
S(mm)
[10-550/1mm Unit(s)]
Clear
type
- BUFSP
- BWFSP
- UFSP
- WFSP
Clear
Material
- SWP-A
Clear
CAD
- 2D
- 3D
Clear

Days to Ship

All

6 Day(s) or Less
Clear

Specify Alterations

The specifications and dimensions of some parts may not be fully covered. For exact details, refer to manufacturer catalogs .

All Categories

Categories

Search by Application

Brands

Message from MISUMI

My Favorites

Settings

How can we improve?

Tension Springs/Configurable Length

(i)Caution

Specifications

Part Number

Basic Information

Configure

Specification/Dimensions

Hook Opposing Angle

Outer Dia. D(Ø)

Initial Tension(N)

Standard Spring Constant(N/mm)

Wire Dia.(Ø)

S(mm)

type

Material

CAD

Days to Ship

Specify Alterations

Tech Support

Payment Method more

About MISUMI

About this Website

Useful Tools

Customer Service

Social Media

MISUMI Contact 9:00 am – 6:00 pm (Mon – Fri), 9:00 am – 3 pm (Sat)