Extension springs are also known as tension springs. They are helical and provide the strength against the tensile force along the axis. Commonly, the cross-section of the material is round. Distance between coils is mostly tight when it is unloaded. Extension springs usually have hooks or rings on both ends for loading, ensuring the connection between items.
They can be seen in medical devices, sports facilities, hand tools, health care, shock absorbers, pump springs, protection of machines/electricity, valves, aircraft, actuators, switches, instrument panels, etc.
Furthermore, JMS also have CNC machines, offering the assembling of machining parts and springs.
Hooks on the ends of extension spring (round wire): English hook, German hook, side hook, universal hook, pointed hook, U hook, swivel hook, etc.
Industry / Field
National defense industry, ocean industry, computer, eletronics, mold, automotive industry, medical and healthcare, biochemistry, aerospace industry, railway, power, engineer machinery, construction machinery, etc.
Piano wire, carbon steel wire, stainless steel wire, phosphor-bronze wire, enamelled wire, etc.
0.06~10.00 mm in diameter
Flat / Round wire
Blacking, gold plating, copper plating, nickel plating, chroming, tin plating, black zinc plating, yellow zinc plating, baking varnishing, etc.
10000~1000000 times of use. Depends on the allowable stress of the material and actual load.
Factory Established Year
1993 at Shulin, New Taipei City, Taiwan
2001 at Kunshan City, China
2004 at Dongguan City, China
ISO, ASTM, BS, DIN, JIS, JASO, SAE, etc.
All process will follow the OEM's demand. If the product doesn't meet the requirement instructed from the drawings or paper document, JMS will refabricate or refund.
1. Individual Package:
One item per plastic bag
For the strong product with appearance concern
For big product
2. Mass Package:
100, 200, 500, 1000 pieces or a specific number of items in one big PE bag.
We will decide how many pieces in a bag unless further request.
For common product
For non-twisted product
For non-scratch-concern product
3. Tray Package
For fragile products with soft material
JMS offers standard trays. Special design of trays upon request with extra charge.
4. Tape on Reel
For SMT machine
JMS offers standard reels. Special design of reels upon request with extra charge.
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Thanks for your interests in JMS Group’s products. Please feel free to contact us if you have any inquiries or opinions about metal parts, CNC machining parts, stamping parts, or springs. We are looking forward to offering you our services.
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