1.Flushing and jet control
A. Objective: To remove air in the system and check the fuel jet.
B. Procedure: Slowly increase the working pressure until straight jets of oil are ejected from the nozzle holes (no atomization).
C. Acceptance criteria: There is to be a continuous jet of oil through all of the nozzle holes.
2.Atomization test
The reason is that the atomization test may damage the valve because it makes the needle oscillate, with a small lift at a very high frequency. The high pressure drop across the cut-off edge and the high contact pressure between slide and fuel nozzle, in combination with the poor lubricity of the test oil, increase the risk of seizures between cut-off slide and nozzle.
3.Opening pressure
A. Objective: To check the opening pressure.
B. Procedure: Increase the oil pressure until oil is admitted through the nozzle holes.
C. Acceptance criteria: Check the opening pressure on the pressure gauge. (350 bar)
4.Sealing test and sliding function
A. Objective: To check the needle valve seat for tightness and the slide for correct closing.
B. Procedure: The control handle must be in the OPEN position. Slowly increase the oil pressure to about 50 bar below the opening pressure. Maintain the built-up pressure by moving the control
handle into the CLOSED position. Repeat the procedure two or three times.
C. Acceptance criteria: Oil must not flow from the nozzle holes. The pressure drops relatively slowly to about 15 bar, after which it drops quickly to 0 (the slide is pressed against the conical seat and opens for circulation oil).
5.Pressure test, O-ring sealings
A. Objective: To ensure that the leak oil (circulation oil) remains in the closed system.
B. Procedure: The control handle is to be in the OPEN position.
Build up a working pressure of about max. 10 bar until oil flows out of the leak oil outlet.
C. Acceptance criteria: Close the leak oil outlet with a gasket and plug screw. Increase the working pressure to about 100 bar. Move the control handle to the CLOSED position. The built-up pressure of about 100 bar should be maintained.
D. Cause of fault: If oil leaks out at the union nut, the O-ring inside the fuel valve head is defective, and must be replaced.
A. Objective: To remove air in the system and check the fuel jet.
B. Procedure: Slowly increase the working pressure until straight jets of oil are ejected from the nozzle holes (no atomization).
C. Acceptance criteria: There is to be a continuous jet of oil through all of the nozzle holes.
2.Atomization test
The reason is that the atomization test may damage the valve because it makes the needle oscillate, with a small lift at a very high frequency. The high pressure drop across the cut-off edge and the high contact pressure between slide and fuel nozzle, in combination with the poor lubricity of the test oil, increase the risk of seizures between cut-off slide and nozzle.
3.Opening pressure
A. Objective: To check the opening pressure.
B. Procedure: Increase the oil pressure until oil is admitted through the nozzle holes.
C. Acceptance criteria: Check the opening pressure on the pressure gauge. (350 bar)
4.Sealing test and sliding function
A. Objective: To check the needle valve seat for tightness and the slide for correct closing.
B. Procedure: The control handle must be in the OPEN position. Slowly increase the oil pressure to about 50 bar below the opening pressure. Maintain the built-up pressure by moving the control
handle into the CLOSED position. Repeat the procedure two or three times.
C. Acceptance criteria: Oil must not flow from the nozzle holes. The pressure drops relatively slowly to about 15 bar, after which it drops quickly to 0 (the slide is pressed against the conical seat and opens for circulation oil).
5.Pressure test, O-ring sealings
A. Objective: To ensure that the leak oil (circulation oil) remains in the closed system.
B. Procedure: The control handle is to be in the OPEN position.
Build up a working pressure of about max. 10 bar until oil flows out of the leak oil outlet.
C. Acceptance criteria: Close the leak oil outlet with a gasket and plug screw. Increase the working pressure to about 100 bar. Move the control handle to the CLOSED position. The built-up pressure of about 100 bar should be maintained.
D. Cause of fault: If oil leaks out at the union nut, the O-ring inside the fuel valve head is defective, and must be replaced.
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