The Spring for the 21st Century

Enter The World of Machined Springs

The spring
for the 21st century
Here's why:

International Space Station spring

In use on the
Hubble telescope

Cryogenic cooler application

Advanced machined spring technology

Testing for stress areas

Finite element stress analysis
(FEA) with Ansys

Modal analysis

Accommodates a wide variety of integrated attachments

Includes pure spring reactions for torsional applications

Incorporates multiple start configurations to eliminate extraneous reaction forces and moments, (buckling)

Provides unlimited variations

Offers multi-functionality expertise

The HELI-CAL® Flexure
The HELI-CAL Flexure is a flexible helix (curved beam) machined into a unique configuration that incorporates
special design requirements, performance features and/or characteristics. The material used is basically unlimited.
When used as a spring, the multifunctional flexure provides desired and predictable elastic performance in compression,
extension, torsion, lateral bending and lateral translation modes. One huge advantage of this technology—it enables
customer specified end-attachments, such as tangs, clamps, flanges or threaded ends, to be integrated into a
single multi-functional component.

Materials

High strength corrosion resistant materials such as stainless steel
High strength aluminum
High strength titanium
All machinable alloys
Machinable plastics

Materials most used: Stainless steel 17-4PH, 15-5PH, 303, 316,316, 18-8, Custom 455 maraging,C300 and C250, 718, 4340, H-11, Beta C Titanium, Delrin 150,Aluminum 7075-T6.

Capabilities/Services

Over 40 years of manufacturing and engineering excellence
Complete in-house engineering design and manufacturing
Quality assurance
Precise spring rates
Prototypes and short runs to high volume production quantities
Fast turn around and delivery
Unmatched dedication to quality and customer satisfaction
“Multi-start” flexure construction (more than one spring coil set) provides a broad range of spring rates and
functionality within a given envelope. Provides a redundant coil to resolve lateral forces.
Precision machining of complex, multi-featured configurations

Wire-wound vs HELI-CAL Machined Springs
Differences in coil geometry enable machined springs to provide more precise performance, features and functions
than can other, more traditional types of springs. There are big differences in performance, reliability,
versatility, integrity, and cost effectiveness.

Before
Wire-wound spring.
Three pieces

After
Helical machined spring. Single piece.
Integrated parts-functions.

The bottom line —machined springs:

Offer more functions in a single spring than other more traditional springs, such as wire-wound.
Add value, in terms of multipart integration, time saved in handling, reliability, rates being linear,
and dimensions being very precise.
Reduce and/or control costs Raise overall productivity, i.e., add more, do more, save more dollars.

Comparison Data — are machined springs right for your application?

Consideration	Wire-wound springs	Machined springs	Comments
Perform basic elastic modes	Yes	Yes	Machined springs have distinct multi-functional advantages.
Relatively inexpensive	Can be	Depends	Both types can be expensive or inexpensive.
Available in different materials	Limited	Yes	Machined springs can be produced from any machinable material.
Multi-function - feature capability	Limited	yes	Machined springs ca contain many dimeensional features.
No stress to overcome before deflection	Some	Yes	Machined springs have a more precise force deflection relation.
Can reduce assembly costs	Doubtful	Yes	Incorporating multiple features into a single part design makes assembly easier & cost effective.
Can contain redundant elastic elements (multiple starts)	No	Yes	Machined spring rates are linear.
Quality - reliability	Depends on manufacturer	Yes	Dimensional variances are typically smaller in machined springs.
Precision elasticity	Difficult	Yes	Variation rates in machined springs are typically low.
Integration with other products	Difficult	Yes	Design it into your system, not around it.
Reduction of system complexity	Difficult	Yes	Simplify your system by incorporating multiple capabilities into a single part.
Custom-end configurations added to spring	With difficulty	Yes	One of the major advantages of machined springs.
Longevity achievable?	Yes	Yes	Machined spring’s long life can benefit from multistart configurations (double and triple starts).

Can be configured as:				Machining lends itself to custom end attachments. With machined springs, all coils deflect under load.
	Extension spring	Yes	Yes
	Compression spring	Yes	Yes
	Torsion spring	Yes	Yes
	Lateral bending spring	?	Yes
	Lateral translation spring	?	Yes

Applications utilizing the HELI-CAL® Flexure range from missiles to medical apparatus to oil wells

Integrated attachment examples of Helical machined spring

Threaded ID and OD	Integrated flange	Double start flexure	Heat dissipating spring

Hubble telescope	Aerospace application	Cryogenic cooler application	Used with lasers
Material: Beta C Titanium	Right and left handed flexure	Threaded Ends	Capacitor terminal

240° torsional spring	Triple start, torsional spring	Mars Rover	Aircraft electronics
Formerly four pieces	Single start, compression spring	One piece, wrap spring clutch	Medical application Five start spring

Now one piece with Helical wrap spring clutch	Single start, compression spring	One piece, wrap spring clutch	Medical application Five start spring
Constant pivot and rotary	Material: 17-4PH	Integrated end attachments	.125” Flexure OD

Medical application Torsion spring	Industrial knife application	Machine tool application	Commercial lateral spring

Worth Noting

Downloadable version of our new The Spring for the 21st Century


	901 W. McCoy Lane · P.O. Box 1069 · Santa Maria, CA 93456-1069 Phone: 805-928-3851 · Fax: 805-928-2369 sales@heli-cal.com · engineering@heli-cal.com
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