Custom Stainless Steel Extension Coil Springs Return Door Coils Spring For Heavy / Light Duty Doors
Product Parameters
(Non-customized) Model Reference Introduction:
1.0 * 7 * 360mm for light doors 40-50cm wide
1.0 * 8 * 360mm for light doors 40-60cm wide
1.2 * 10 * 380mm for 60-70cm wide domestic doors
1.2 * 10 * 390mm for 60-70cm wide domestic door
1.2 * 10 * 440mm for 70-80cm wide domestic door
1.5 * 10 * 430 mm for wide/heavy doors 70-80 cm wide
1.5 * 12 * 450mm for wide/heavy doors 70-80cm wide
1.5 * 12 * 500mm for 80-120cm wide door/heavy door
The extension spring is a spiral spring that bears axial tension. Its hook forms include side hook tension spring, long hook tension spring, British hook tension spring, German hook tension spring, semicircular hook tension spring, duckbill hook tension spring, etc. "Hook" is used to ensure the tension source of the extension spring. It is generally made of spring steel with circular section material. When it does not bear load, The coils of the tension spring are generally tight without clearance and work with the resilience (tension) after stretching to control the movement of the parts, store energy, measure the force, etc. Most tension springs are usually under a certain degree of tension, even without any load.
STEP ONE
Material & Suface Treatment
Choose material:
Carbon Steel
Alloy Steel
Non-ferrous Alloy Steel
Stainless Steel
Surface treatment:
Audited Supplier 
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