Extension Springs

Custom Extension Spring Supplier and Manufacturer

The extension spring is also called a tension spring, which is a kind of helical spring that bears the axial tension. The extension spring is generally made of circular section material. While there is no load, the coils of the tension spring are generally tight, and there is no gap between the coils.

Tension springs can be used on many occasions, such as production assembly, experimentation, research and development, maintenance, etc.

KENENG specializes in the design and production of custom and stock compression springs of multiple sizes and configurations. We are an excellent tension springs supplier. We have excellent manufacturing capabilities to produce and secure a wide variety of end, length, and pitch configurations, materials, application finishes, and optional certifications. We also stock many standard extension springs.

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Extension Springs Display

Custom Extension Springs

KENENG is a custom extension spring manufacturer. We produce both standard extension springs as well as custom sizes and styles.

Non-standard spring customization needs customers to coordinate design and production with us, according to the actual use of the environment, installation space, pressure size to choose the material of the spring, line diameter, size, and special surface finishing.

Please inform us of the following basic data when ordering, so as to customize.

1. Specifications: Wire diameter, OD(Outside diameter) or ID(Inside diameter), Free length, Coil numbers, Active coil numbers.

2. Technical requirements:

  • Turing direction (left hand/right hand)
  • Material(music wire, spring steel, carbon steel, stainless steel, copper/brass, Ti/Ti alloy, super alloy, etc)
  • Surface finishing(black oxide, galvanized, nickel plated, gold plated, silver plated, phosphating, color coding, shot peening, sandblast, etc)
  • Spring force
  • End type (Closed, Grounded, Close and grounded, Open)
  • Hook form (round hook/half round hook/U hook/middle ear/side hook)

If you have any needs, please contact KENENG, we will provide you with the best quality service.

Case Products of Extension Springs

Tension springs are widely used in many fields around the world, including molds, construction machinery, ships, electronics, automobiles, medicine, aerospace, railways, wind power, thermal power, mining machinery, national defense, etc.

We always adhere to the principle of “quality first”, select qualified materials, adopt advanced equipment, use professional production technology, adhere to a serious, responsible, United, and innovative working attitude, produce high-quality products, and provide humanized services, which has won the recognition of customers at home and abroad. As a popular extension spring manufacturer, we welcome customers at home and abroad to negotiate business. We will welcome you with high enthusiasm!

Types of Customization You Can Choose From


  •  Music wire
  • Spring steel
  • Carbon steel (65Mn, 60Si2MnA, 55SiCr, 50CrVA, etc.)
  • Stainless steel (201, 304, 316, 316L, etc.)
  • Copper/Brass
  • Ti/Ti alloy
  • Monel
  • Hastelloy
  • Inconel


  • Wire diameter 0.1~80mm
  • OD and length as per customer’s requirements.


  • Black oxide
  • Plating (Zinc, Nickel, Tin, Gold, Silver )
  • phosphating
  • powder painting & color coding
  • shot peening
  • sandblast


  • production assembly
  • experimentation
  • research and development
  • national defense
  • marine
  • computer
  • electronics
  • automobile
  • mold
  • medicine
  • biochemistry
  • aerospace
  • railway
  • nuclear power
  • wind power
  • thermal power
  • construction machinery
  • mining machinery
  • elevators, etc.

Materials We Can Use on Extension Springs

The Order Process of Extension Springs

the order process of springs

Related Products

Extension Spring Manufacturer in China:

KENENG has been focusing on the design, development, manufacturing and surface treatment of extension springs for 17 years.

Advantages of KENENG:

1. It can process and produce various 0.1-90mm compression springs, tension springs, torsion springs, disc springs, leaf springs, special-shaped springs, etc.

2. Our company has complete production and testing equipment and advanced production technology. It has various specifications of fully automatic computer spring coiling machine, computer spring grinding machine, continuous mesh belt quenching furnace, tempering furnace, spring tension and compression testing machine, spring fatigue testing machine,  cold coil spring machine, hot coil spring machine, etc.

Production equipment for Extension Springs

What Processes Can We Use to Produce Extension Springs?

Production Equipment for Extension Springs

Application Industries of Extension Springs

For Example:

Related News


a. The design and manufacturing parameters of non-standard spring are unreasonable: only pay attention to the outer diameter, inner diameter, length and other parameters, and often ignore the size of wire cross-sectional area and pitch, resulting in smaller force;

b. Unreasonable model selection of standard spring: due to the low price, the light load type is selected and cannot bear the heavy load;

c. Wrong spring quality grade: inadvertently or deliberately use ordinary springs as high-quality springs or imported springs;

d. The elasticity is reduced or even lost due to the use at a temperature exceeding the specified temperature;

e. The spring wire itself is too soft, or the quenching temperature of the spring is too low or the holding time is not long enough, or the tempering temperature of the spring after forming is too high and the time is too long, resulting in insufficient tensile and compressive strength.