EN ISO 7285 : 2021 Pneumatic cylinders for mechanized multiple spot welding.
6? Operating? specifications
6.1 Nominal force
The nominal force shall be given at a pressure of 1 MPa (10 bar) with a tolerance of ± 5 %.
6.2 Return force
The return force shall not be less than 40 % of the nominal force.
6.3 Maximum supply pressure
The maximum supply pressure is 1,6 MPa (16 bar).
7 Construction
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 — 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).
7.6 Leakage
The bodies of the cylinders shall not leak in normal conditions of use (to check this, see 10.5).
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.
7.9 Endurance
The cylinders shall be able to withstand the endurance test described in 10.8 according to the requirements of 10.8.5 and 10.8.6.
7.10 Finish
The outer surfaces shall be protected against cor rosion.
EN ISO 7285 pdf download.