E-MAIL: info@connexusa.com Voice: 814-474-4550 Fax: 814-474-4577

CONNEX Inc. 7660 Klier Drive N., Fairview, PA 16415

 

 

 

 

 

 

 

Seating Capacity/Insertion Force

Determination of insertion force of the spring bushing

The insertion force is the maximum force required to press the spring bushing into the housing. It depends on how much the bushing is oversized in reference to the nominal OD, the tolerance of the housing bore, the chamfer, the tooth spacing and lubrication used in assembly. An increasing force is applied to the spring bushing until it enters into the housing bore. The force is measured and is classified as the insertion force.

Determination of spring bushing seating capacity

The seating capacity of the spring bushing corresponds with the pressing force necessary to move the bushing out of the house bore, i.e., to overcome static friction. Inspection bores used for test purposes are, as a rule, more precise than housing bores of manufacturing components. Therefore, laboratory results are for reference values only. It should be noted that the ejection force is somewhat lower than the insertion force. Approximate Ejection Force of Some Bushing Sizes

 

 

 

 

 

 

 

 

1 1/2 x 1 1/4 x 1 1/4

450 to 675 lbs

2 x 1 1/2 x 1 1/2

495 to 715 lbs

2 3/8 x 2 x 2

560 to 785 lbs

2 3/4 x 2 3/8 x 2 3/8

580 to 800 lbs

3 1/4 x 2 3/4 x 2 3/8

675 to 900 lbs

3 1/2 x 3 x 2 3/4

785 to 1000 lbs

 

 

 

 

In many applications, the seating capacity is a dominant factor. It is important that the tolerance of the housing bore meet the requirements of our standards.  Please contact a Connex representative for the recommended housing diameters.

When higher seating capacity is needed, special measures may be incorporated in manufacturing. These must be agreed to by the customer.

CONNEX® Spring Bushing Materials

Spring Steel AISI 6150

Because high resistance to wear and shock loads are required in spring bushings applications, material quality is an important consideration. That is why a high quality spring steel AISI 6150 was selected.

 

 

 

 

 

 

 

 

Chemical Analysis:

Carbon 

0.48-0.53

Silicon

0.15-0.30

Manganese

0.70-0.90

Phosphorus

0.035 Min

Chrome

0.80-1.10

Sulfur

0.040 Min

Vanadium

0.15 Min

 

 

 

 

 

CONNEX Spring Bushings are hardened through to a Rockwell C of 44 to 50. For special applications, the hardness can be lowered or increased depending on the requirements.

Spring Bushing Insertion

The recommended way to install our bushing is by using a hydraulic press. However, in practice a hammer and soft mandrel are often used to avoid damaging the bushing. In addition, assembly using pneumatics for insertion is also used.

Compared to solid bushings, insertion of the CONNEX Spring Bushing is much simpler. The insertion force of a spring busing is smaller compared to that of a solid bushing. Also, tolerances of the housing bore need not be as close as they are for a solid bushing.

Manufacturers are aware of the problems of a solid bushing being damaged during assembly which could result in seizure. Freezing of the parts before assembly helps, but this procedure is both costly and impractical.

The advantages of spring bushings are especially valued in the construction and farm machinery industry where on-site replacement is often necessary.

Spring Bushing Hardness

 

 

 

 

 

 

 

Hardness Comparison Table:

Rockwell HRc

Rockwell Hra

Vickers HV

Tensile Strength PSI*

44

72.5

434

208,000

45

73.1

446

215,000

46

73.6

458

221,000

47

74.1

471

229,000

48

74.7

484

238,000

49

75.2

498

246,000

50

75.9

513

255,000

51

76.3

528

264,000

52

76.8

544

273,000

53

77.4

560

283,000

54

78.0

577

292,000

55

78.5

595

301,000

56

79.0

613

313,000

57

79.6

633

325,000

58

80.1

653

338,000

59

80.7

674

351,000

60

81.2

697

364,000

*Inexact and only for steel

 

 

 

 

Spring Bushing Lubrication

CONNEX Spring Bushings are normally used in highly loaded bearing applications and, as a rule, are not lubricated. However, in some applications, the use of a lubricant with graphite grease serves to reduce noise and restrict the entry of contaminates.

Materials Selection and Component Safety

High bearing loads require suitable materials for both bushing and shaft. Suitable shaft materials are AISI 1045 (fg), 4140, 5060, 8620 or other case hardening steels, which can be hardened to a depth of .023 to .030 at Rockwell C 55 to 60. This depth of hardness must be maintained if grinding is to be performed on the shaft. The shaft hardness is an important consideration for component safety and any wear could have an adverse effect on the load carrying capacity. Because the CONNEX Spring Bushing is normally designed as a wear part, it has the additional advantage of being easily replaced.

The Connex® Principle

Application of Connex® Spring Bushings

Properties of the Connex® Spring Bushings

Seating Capacity/Insertion Force

Bearing Load Calculations for Connex® Spring Bushings

Connex® Spring Bushings Form 1...cold rolled with finished ends- Material: AISI 6150

Connex® Spring Bushings Special Options

The Quality Assurance System

Examples of Applications Using Connex® Spring Bushings

 

 

 

 

 

 

 

 

 

 

E-MAIL: info@connexusa.com Voice: 814-474-4550 Fax: 814-474-4577

CONNEX Inc. 7660 Klier Drive N., Fairview, PA 16415