 |
| |
Reg. 507, Reg. 508
STANDARD CONDITIONS FOR THE DESIGN AND
CONSTRUCTION
OF ECONOMISER, FEED PIPES, FEED HEATERS AND OTHER SIMILAR
VESSELS
CAST IRON, TUBES AND HEADERS
Test bars |
|
For all new economisers the hydraulic test must be
applied as shown below:-
| a) |
When the test bars are
cast separately, they shall be poured at the same
time and from the same ladle of metal as the casting
or castings they represent. The number of test bars
specified in Regulation 508 shall be applicable
to all castings of each melt. |
| b) |
when the bars are cast
on the mould for the castings and the mould for
the test piece shall be joined together in such
a manner that the liquid metal fills both moulds
at the same operation. |
| c) |
all test bars shall be
cast in green sand or in loam or dry sand moulds
according as to whether the casting or castings
they represent are moulded in green sand, or in
loam or dry sand respectively. |
| d) |
The test bars shall not
be subjected to any heat treatment after leaving
the moulds except where the castings are heat-treated. |
|
|
|
Reg. 508
STANDARD CONDITIONS FOR THE DESIGN AND
CONSTRUCTION
OF ECONOMISER, FEED PIPES, FEED HEATERS AND OTHER SIMILAR
VESSELS
CAST IRON, TUBES AND HEADERS
Number of tensile tests |
| |
|
(a) The number of tests required for each batch of
castings shall be in accordance with the following table
the various classes of castings being divided into 4
representative groups:-
| Group |
Weight of castings |
Test requirements |
| 1. |
Up to 28
lbs |
One
test for each 30 cwts. Of castings or part thereof.
One test for each 2 tons of castings or part thereof.
|
| 2. |
Over 28
lbs. and up to 1 cwt |
| 3. |
Over 1 cwt. And up to
1 ton |
One test for each 3
tons of castings or part thereof. |
|
In the above Group 1,
2 and 3, all castings represented by one test must
be poured from the same ladle of same heat as the
bar or bars provided for the test.
|
| 4. |
Over 1 ton and important
castings |
One test for each 4 tons
of castings or part thereof or for each casting
weighing 4 tons or more. |
(b) Conditions for Acceptance and for Rejection:-
| Test |
Result |
Conclusion |
| 1st
|
Pass |
The batch or separate
casting represented shall be accepted. |
| Tensile or Transverse
test fails |
Two more tests shall
be made. |
| 2nd |
If both pass
If either fails |
The batch or separate
casting represented shall be accepted.
The batch or separate castings represented shall
be rejected. |
Provided always that, in the case of failure of any
test piece showing obvious casting defects, another
test piece shall be taken from spare test bars or cut
from a casting from the same batch and the results obtained
from this substituted for those obtained from the defective
test bars.
|
|
|
