Yokogawa Advanced Reflux Sampler - Manual (Page 14)

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All Rights Reserved. Copyright © 2011, Yokogawa Electric Corporation. Subject to change without notice. April 2011 IM 11A00V01-01E-A
inlet of the Vortex Tube while it is operating. Restrictions in the compressed air supply line can cause excessive
pressure drops and deteriorate performance.
3.) Inlet Temperature- A Vortex Tube provides a temperature drop from supply air temperature. In some cases, the
supply air is warmer than ambient air due to compressed air lines running across ceilings, near furnaces, direct sun,
etc. In this case, the cold air may be warmer than anticipated and adequate refrigeration may not be available for the
application.
4.) No Cold Flow- If the Vortex Tube is operated continuously for an extended period of time and is set for more than
a 50ºF (25ºC) drop from the compressed air temperature, the cold end may freeze, blocking the cold outlet. If this
happens, any one of the following will correct the problem:
a. Blow air (use an air gun) into the cold end with the Vortex Tube off.
b. Turn the Vortex Tube off for a few minutes. It will thaw.
c. Use dry air with an atmospheric dew point of -40º or less.
5.) Back Pressure - The performance of a Vortex Tube deteriorates with back pressure on the cold air exhaust. Pressure
up to 2 PSGIG (0.1 BAR) will not change performance. 5 PSIG (0.3 BAR) will change performance by approximately
5ºF (2.8ºC). If cold air ducting is used, the total-cross-sectional area should be equal or greater than the area of the
Vortex Tube cold air exhaust.
10.2 Installation and Maintenance Instructions for Control Valves
10.2.1 General Safety Information
These products are designed and constructed to withstand the forces encountered in normal use. The normal operation
and limits for temperature and pressures are stated in the General Specifications in section 2.
Safe operation of these units can only be guaranteed if they are properly installed, commissioned and maintained by a
qualified person in compliance with the operating instructions. General installation and safety instructions for pipeline and
plant construction, as well as the proper use of tools and safety equipment must also be complied with.
10.2.1.1 Warning - Laminated gaskets
The metal foil sheet used to reinforce gaskets is very thin and sharp. Care should be taken when handling to avoid
the possibility of cuts or lacerations to fingers or hands.
10.2.1.2 Isolation
Consider whether closing isolating valves will put any other part of the system or personnel at risk. Dangers might
include; isolation of vents and protective devices or alarms. Ensure isolation valves are turned oft in a gradual way to
avoid system shocks.
10.2.1.3 Pressure
Before attempting any maintenance consider what is or may have been in the pipeline. Ensure that any pressure
is isolated and safely vented to atmospheric pressure before attempting to maintain the product, this is easily
achieved by fitting Yokogawa depressurization valves (see separate literature for details). Do not assume that the
system is depressurized even when a pressure gauge indicates zero.
10.2.1.4 Temperature
Allow time for temperature to normalize after isolation to avoid the danger of burns and consider whether protective
clothing (including safety glasses) is required.
10.2.1.5 Disposal
These products are recyclable. No ecological hazard is anticipated with the disposal of these products providing
due care is taken.