InformationCompressionSpringSelection
Material
Patented drawn spring steel wire in compliance with EN 10270 part 1 type DH for all wire diameters up to 1.9 mm. For diameters between 2.0 and 10.0 mm type SH will be used (AMS 5112 / BS 5216-75). Our stainless steel springs are manufactured using spring steel wire material no.1.4310 in compliance with EN 10270 part 3 (AISI 302 / BS 301S21). The tolerances of the wire diameters comply with DIN 2076.
Design
The springs are right-hand coiled (clockwise).
right-hand coiled
A 1/1 German loop in compliance with DIN 2097 is fixed to each end of the spring.
1/1 German loop
Each of our extension springs is available with a choice of 2 different loop positions. One of the positions is 180 ° (indicated in the table by an catalogue number which ends with the letter "I".) In this case the loops are parallel, the loop ends are set at 180°(as in a right-hand screw).
loop position 180 degrees (I)
The other loop position is 270° (indicated by an catalogue number which ends with an "X") In this case the loops are positioned cross-wise. The loop ends have been turned through 270°.
loop position 270 degrees (X)
Loops are stocked without openings (m=0). However it is possible to have an opening cut into the loop at an extra cost, without causing any delay.
Surface treatment
Extension springs made of spring-steel wire EN 10270-1-DH and -SH will be ligthly oiled after the thermal coating. Springs made of material no. 1.4310 will not be re-coated after the thermal coating, as a surface protection is not normally required. All subsequent surface treatments cause unavoidable delay, as the application of a protective layer between the coils is very difficult due to the preset nature of the spring body. Here the selection of a suitable material should be made for an additional surface coating.
Use
Extension springs can be used with the stated deflections and loads by dead or infrequent strains. In all other cases an arithmetical check of the application of the spring should be carried out. It is crucial to check the stresses at the point of attachment of the loop to the body, as this is the critical point for possible fractures. A longer life-span can often be attained by choosing a different loop type.
Production compensation
In order to maintain the stated tolerated measurements we need to carry out production compensation with either the pre-stress (F0) or the wire diameter (d).
Quality control
Extension springs are tested for compliance to the tolerated loads and measurements before they are approved and reach the production warehouse. The tests take place in our quality control department according to DIN ISO 2859-1 level II. The procedure normally consists of a simple spot check programme, test-level AQL=1.0. Specific tests can also be carried out and documented for each individual spring upon the customer's request. The following charges apply for the quality control certificates issued by us.
In compilance with:
DIN EN 10204-2.1 (DIN 50049-2.1)
DIN EN 10204-2.2 (DIN 50049-2.2)
DIN EN 10204-2.3 (DIN 50049-2.3)
DIN EN 10204-3.1B (DIN 50049-3.1B)
Testing of prototypes
Calculation
The calculation and design of the extension springs is carried out in accordance with EN specification 13906, section 2. DIN 2097 Grade II is taken as the basic standard for the tolerances.
spring materials
Here you can see a selection of our normal spring materials, they we have on stock. In all questions to the right selection of spring material, please contact our Department Engineering:
Gutekunst Federn · Dep. Engineering · Gewerbegebiet · D-02733 Cunewalde
Tel. (+49) 035877/227-11 · Fax (+49) 035877/227-14 · technik@gutekunst-co.com
surface treatments
Here you can see a selection of our normal surface treatments, they we can produce for you in addition. In all questions to the right surface treatment, please contact our Department Engineering:
Gutekunst Federn · Dep. Engineering · Carl-Zeiss-Strasse 15 · D-72555 Metzingen
Tel. +49 (0)7123 960-193 · Fax +49 (0)7123 960-150 · technik@gutekunst-co.com