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TECHNICAL REQUIREMENTS:
- Disc springs with bearing surfaces shall conform to group 3 din 2093
- Disc spring stack consists of no of disc springs assembled in single
series
- Individual disc spring is to be tested with spring force P0.75 at
disc height L0.75 and combined testing of the spring stack is to be
done as per Spring diagram.
- The test shall be done with the help of two pressure plates provided
on both the sides which shall be harden ground and polished, using suitable
lubricant.
- Values encircled as shall be measured and recorded by supplier on
test certificate values of and are for reference only.
MANUFACTURING METHODS.
5.1 Disc are to be manufactured by hot forming
5.2 Disc are to be machined all over and sharp edges to be rounded off
5.3 Concentricity of diameter should be within 0.5mm
- HARDNESS SURFACE AND SCRAGGING.
6.1 The decarburization of disc springs after heat treatment should
not exceed 3% of disc thickness
6.2 Hardness of each disc should be within 42 to52 HRC
6.3 After heat treatment disc spring must be subjected to scragging,
to ensure that after being loaded at twice the force P0.75 the free
height of disc does not vary
6.4 The surface must be free from defects viz crack, pits, rust, spots,
etc.
- Anti corrosive coating on disc springs can be Phosphatising, ZN OR
CD plating as per suppliers choice.
- Material test certificate should include chemical properties and
hardness of disc springs.
- Identification of springs as per HW 040397 at a places marked with
the in identification marking should not dissolve in turbine oil and
fire- resistant fluid (phosphate esters).
- In addition each disc spring shall be marked with stack no and disc
No. Disc No.2 of stack no 1 shall be marked as I/?.
- Disc springs shall be property tied together and packed to avoid
intermixing and damage during Transit and storing.
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