EN ISO 7285:2021 pdf download.Pneumatic cylinders for mechanized multiple spot welding
1 Scope
EN ISO 7285 specifies the requirements of the geometrical and mechanical characteristics of pneumatic cylinders used for multiple spot welding machines and their manufacturing,delivery and test specifications.
These cylinders for a nominal air pressure of 1 M Pa (10 bar) are double-acting, with two piston stages in series for the advance during the operational stroke and the force, and a single piston stage for the return.
2 Normative reference
The following standard contains provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the edition indicated was valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent edition of the standard indicated below.Members of IEC and ISO maintain registers of currently valid International Standards.
ISO 4394-1:1980, Fluid power systems and components一Cylinder barrels一Part 1: Requirements for steel tubes with specially finished bores.
5.1 Outside dimensions
Depending on the method of mounting the cylinder, the nominal force and the nominal stroke, the cylinders shall have the dimensions indicated in the drawings in annex C taking into account the characteristics of the electrode holder attachment indicated in annex B.
7.1 Point of application of the reaction
The cylinders shall function correctly when the reaction to the nominal force is being applied at a maximum distance of 28 mm from the axis of thrust.
7.2 Piston rod
The sliding bearing surfaces of the rod shall have an adequate hardness to avoid friction, wear,oxidization and any scale caused by sputtering (sparks).
7.3 Rotation
The piston rod assembly is considered as nonrotating. The anti-rotating device shall withstand, without being damaged, a rotary torque of 150 N-m applied in either direction and at any point of the travel of the piston rod.
7.4 Seals
The seals shall be compatible with fluids used to lubricate the cylinder.
7.5 Perpendicularity 一Parallelism between the mounting point and the attachment
Any faults in perpendicularity or parallelism of the bearing surface of the body of the cylinder with respect to the axis of the shank cone of the electrode holder shall not exceed 0,2 % (for inspection, see 10.2).
7.7 Behaviour under pressure
The body of the cylinder shall be able to withstand without being damaged a test pressure equal to two times the maximum supply pressure applied for 1 min in each direction (see 10.4).
7.8 Electrode holder attachment
The electrode holder attachment shall be completely electrically insulated with respect to the body of the cylinder (to check this, see 10.3). This subclause does not apply to electrode holder attachments according to Nos. 13 and 22.EN ISO 7285 pdf download.