Degassing Heat Treatment
Procedure No. :
STD Degassing
Ref. No.:
GENERAL
Item
Item Number
Revision
Spec. Number
:
:
:
:
Code/Test. Std
:
Base Metals
Thickness
:
:
Date
0
:
Drawing Number(s) :
BASE METALS
& RULING THICKNESSES
Group no.
mm
PROCEDURE
TIME
T3 .
CR1
HR2
T2 .
CR2
HR1
T1 .
Temperature T1
Temperature T2
Temperature T3
:
:
:
AMBIENT
150°C.
400 ± 10°C.
Time at temperature (T3)
Heating
Heating
Cooling
Cooling
:
rate
rate
rate
rate
HR1
HR2
CR1
CR2
:
:
:
:
T
E
M
P
E
R
A
T
U
R
E
100°C/Hr Max
150°C/Hr Max
150°C/Hr Max
Still air
180 Minutes Minimum
HEAT TREATMENT METHOD & LOADING
Method
: Gas fired furnace or electrical resistance pads
Loading : The components are to be supported and protected in such a way as to prevent localised hot spots, distortion and
contact with the furnace walls. A minimum of 100mm free space is to be left around the components.
TEMPERATURE RECORDING
The temperature are to be recorded by continuous recording charts using directly attached thermocouples(attached by ceramics
or resistance welding). 2 TC per Header, Top and bottom of the header on the thickest part. The frequency and method of
equipment calibration shall be in accordance with standard procedures and works instructions.
DOCUMENTATION & CERTIFICATION
A certificate stating the item tag no., actual soak time, soak temperature, heating/cooling rates and the date of heat
treatment is required. This certificate is to be signed by the responsible personnel. The original recorder chart stating
the item tag no., date of heat treatment, the technicians name and signature and the scales represented by the recording.
REMARKS
APPROVAL
Manufacturer
Designation
Manufacturer
Quality dept.
Approval
Approval
Signature
Date
Stamp
A
Status
PWHT Procedure
Page 1 of 1
B
C
A
B
C