extension spring

extension springs, also called tensile springs, are found in many applications, such as common household products,snow plows, garage doors and various types of spring tensioning devices.

Extension springs have hooks on their ends to attach them to the application. Various hook styles and configurations are available depending on the particular application.Unlike compression springs, extension springs do not have a solid stop to prevent overloading. For these reasons,design stresses are generally lower for extension than compression springs.

1、Wire diameter: 0.08mm-7mm

2、Technical norms:  we produce springs according to customer’s
requirements including spring drawings or qualified samples.

3、Surface treatment:  blackening, zinc plated, nickel plated, gold
plated, silver plated, electrophoresis, Dacromet and so on.

4、Materials:

①  Stainless steel: SUS301，SUS302，SUS303，SUS 304，SUS305，SUS 309，SUS310，SUS 316，SUS321，SUS 403，SUS410，SUS 420，SUS430，SUS630，SUS631

②   Carbon steel(SWC): 60SizMNA、60SizCRVA、55CrSi and so on.

③   Music wire：SWPA，SWPB

④   Copper wire：phosphorus Cooper wire，tinned wire，nickel-coated copper wire，bronze，Becu  and so on.

⑤   resistance wire

5、Delivery date: 5-7 days (transportation time is not included). For the urgent orders, we have our urgent procedure to make sure deliver our goods ASAP.

6、Samples making:  The sample fee is required but it will be returned in full if we cannot meet the customers’ requirements. After a certain amount of order, the samples fee may offset thepayment of the goods.