 |
|||
|
|
|||
| ||||||||||
|
|  MIL-P-23504(Wep)
4.4.4
Operational Check: The vacuum pump shall be subjected to and shall
satisfactorily complete the following tests before acceptance, and shall ex-
hibit no malfunctions, leaks, excessive vibration, or other adverse operation-
al characteristics.
4.4.4.1
Individual Proof Running: The vacuum pump shall undergo an opera-
tional proof run of not less than 12 hours utilizing tricresyl phosphate.
The proof run time shall be divided as fellows and in the order listed:
(a) Four (4) hours of continuous operation at rated speed with the
vacuum pump inlet and discharge connections open to atmospheric pressure.
(b) Four (4) hours of continuous operation at rated speed with the
vacuum pump inlet pressure maintained between 50 and 500 microns Hg absolute.
(c) Four (4) hours of continuous operation at rated speed with the
vacuum pump inlet hose completely blanked off except for a connection to the
absolute pressure measuring device. The absolute pressure attained at the
inlet shall be recorded at intervals not to exceed 15 minutes throughout this
operation. Failure of the pump to obtain and maintain 10 microns Hg or less
shall be cause for rejection.
4.4.5
Performance Mechanical Inspection and Tests
Initial Teardown Inspection: The vacuum pump used for testing shall
4.4.5.1
be disassembled and inspected prior to further tests. All wearing parts and
all parts subjected to high stresses in operation shall be accurately
measured, ferrous parts shall be subjected to magnetic particle inspection in
accordance with MIL-I-6868, and non-magnetic parts shall be inspected with
flourescent penetrant (black light) in accordance with MIL-I-6866 for compari-
son with like inspections to be performed after completion of the tests. The
vacuum pump shall be reassembled and subjected to the remainder of the tests.
Performance Demonstration: The vacuum pump shall be tested in ac-
4.4.6
cordance with the following procedures to determine its performance capabil-
ities prior to endurance testing, Any malfunctions or unusual operating
difficulties occuring during the tests shall be recorded. Failure to meet
the performance requirements of Section 3,6 shall be cause for rejection.
Free Air Pumping Rate: The vacuum pump shall be operated at rated
4.4.6.1
speed until its free air pumping rate, the number of actual cubic-feet
measured at ambient conditions it will pump through per minute when both in-
let and discharge are at atmospheric pressure, has been determined. The
free air displacement shall be measured by means of a flowmeter connected to
the inlet opening. The duration of this test shall be not less than 2 hours.
Ultimate Vacuum: The vacuum inlet hose flange shall be blanked off
4.4.6.2
except for a connection to the absolute pressure measuring device and oper-
ated at rated speed with the discharge open to atmospheric pressure until the
16
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals