Steam & Water Analysis Systems (SWAS)
Steam and Water Analysis Systems
Mechatest is a global company and well known for it’s excellent quality water, steam sampling and analysis solutions built as per ASME PTC 19.11 and VGB/DGRL.
The Steam and Water Analysis Systems (SWAS) are designed with worlds best-in-class instrumentation parts to keep the reability of your water steam analysis safe at all times and to protect your plant from corrosion and scaling.
As an independent System Integrator our main activities are the complete design, engineering, procurement, assembly and integration of steam and water sampling, conditioning, and analysis systems for the power cycle industry, we design accordingly to VGB/DGRL and ASME PTC 19.11 which discuss the methods and instrumentation for testing boiler make-up and feedwater, steam, and condensate in relation to performance testing.
As a result, you save maintenance costs, minimize downtime and prolong the operational life for your plant.
Predesigned SCS for water condensate measurement applications.
- Built as per standard VGB/DGRL and guidance ASME PTC 19.11 Steam and Water Sampling, Conditioning, and Analysis in the Power Cycle.
- Compact design with best selection of top of the world fabricate components
- Efficient temperature cooling with Sentry sample coolers, pressure reduction with Sentry VREL and flow control
- Grab sample capability
- Including Swan Back Pressure Regulator BPR for constant pressure and sample flow for up to 4 water analyzer applications
- Custom options are available to fit your needs
- Manufactured by Mechatest Sampling Solutions.
Sample Conditioning Panels are designed for proper conditioning of your steam and water samples. We take care from sample tap to sampling conditioning and analysis.
Mechatest standard sample conditioning panels for steam and water sampling purposes, the conditioning systems has the main function to reduce and regulate the temperature, flow and pressure of the sample. This kind of sampling panels are mostly used in combination with water analyser equipment for analysis on chemical parameters like conductivity, pH, dissolved Oxygen, Silica, Sodium etc.
The panels are designed with best quality products for safe operation and representative sample at the desired pressure and temperature.
Mechatest is taking care of the following sections;
- Section 2: Sample Point and Analysis Selection Criteria
- Section 3: Obtaining the Sample (we can make probe vibration calculations and help you select standard or Isokinetic sampling nozzle)
- Section 4: Transporting the Sample (we can make lagtime, liquid velocities and pressure loss calculations and help you select best sample transport tube sizing in combination with the desired sample flow rate)
- Section 5: Sample Conditioning
- Section 6: Sample Analysis and Instrumentation (we are independent and can select best analyser fabricate and analysis for your application in general purpose area or Explosion proof area)
Steam Sampling Standards
- ASME PTC 19.11-2008 Steam and Water Sampling, Conditioning, and Analysis in the Power Cycle
- ASTM D1066 Standard practice for Sampling Steam
- ASTM D1192 / D3370 Standard Guide for Equipment and Practices for Sampling Water and Steam
- ASME PTC19.11 The specification requires a ""isokinetic sample nozzle" for representative sampling of the specific two-phase saturated steam flow via sample ports drilled in the side of the nozzle facing the steam flow.
- SO 5667.7 Water Quality-Sampling – Part 7: Guidance on sampling of water and steam in boiler plants
- VGB/DGRL
Steam Sampling Components
Steam Sample Coolers
- Single Helical Tube Sample Cooler
- Compact, high efficiency sample coolers for cooling high temperature/high pressure liquid or gas samples
- Temperature ratings to 593°C at 345 barg (1100°F at 5000 psig)
- Models available for ultra-supercritical power plants with temperature ratings to 621°C at 356 barg (1150°F at 5175 psig)
- Exotic materials such as titanium, Inconel® and Hastelloy® on the tube side, and Monel®, cupronickel, and stainless steel on the shell side are available
- Highest efficiency sample cooler commercially available
- Various configurations available to meet EPRI/ASTM/ASME sampling guidelines
- Many models are available with ASME section VIII code stamp, CE or CRN registrations
- No dead spots or crevices
- Sample flow rates up to 5.7 liters per minute (1.5 gallons per minute GPM); for higher flow rates see
Steam Pressure Reducing Valve Sentry VREL
- High Pressure Sample Flow Control Valve
- The VREL® is an adjustable sample pressure reducerfor sample pressures above 34.5 barg (500 psig) according to the Annual Book of ASTM Standards, ASTM Designation D3370. A precisely machined tapered rod assembly moves inside precision holes within the barrel of the VREL®. Pressure drop is a function of the length of the rods inserted into the barrel.
Sentry Thermal Shutoff Valve (with reset button)
- Shuts down high temperature sample in less than 5 seconds.
- Need to reset by push button after sample is cooling down
- Protect operators, analyzers and sampling components from high temperature liquids with a Sentry Thermal Shutoff Valve. The sensor/actuator is directly exposed to the sample, providing quick reaction time. Economical and highly reliable replacement for solenoid shutoff valve and temperature controller.
- Suitable for system pressures up to 4400 psi (303 bar)
- Totally mechanical design requires no electricity, air, or hydraulics
- Optional dry contact for remote indication
- Standard trip temperature is 120ºF (49ºC) with other temperatures available
- 316 Stainless Steel construction
Thermal Shutoff Valve (automatic)
- Thermal Shutoff Valve (automatic)
- ThermOmegaTech
- Protects expensive and delicate sample analyzers
- Automatically resets when sample cools
- No outside power required
- Superior value vs. more expensive electric valves
Design Features
- Self-operating thermal actuator controls flow based on fluid temperature
- Operating temperatures unaffected by variable inlet pressures
- Wide choice of setpoints available
- Ram-type plug provides tight shutoff
- Corrosion resistant: all stainless steel construction
Typical Applications
- Excessively hot samples can cause damage to expensive and sensitive hardware and electronics. For process analyzers and similar instrumentation, it is important to assure that the process samples fluids are always below the maximum allowable temperature for such instruments. Sample coolers are commonly used to reduce sample temperatures to the acceptable limits. In the event of a loss of cooling fluid to the sample cooler, or if the desired sample temperature is exceeded for any reason, the HST valve will close to prevent equipment damage. HST valves are covered with our standard 36 month prorated warranty.
Operation
- The HST (High Sample Temperature) safety shutoff valve is used to sense the sample temperature after the sample cooler. The sample passes through this normally open valve whenever the sample temperature is below the valve setpoint. If the sample temperature exceeds the valve setpoint, the HST closes to protect expensive and delicate analyzers and other instruments from overtemperature damage. When the HST cools below the setpoint, it will automatically reset open again.
Refillable Cation Exchange Resin Columns
- Minimize "dead volume" assuring representative samples
- Three models* (RC-100, RC-200 and RC-400) meet your specific requirements, withstanding the demands of power plants
- Column(s) provide optimum fluid velocity with increased resin efficiency
- Color-changing resin gives quick visual indication of resin depletion level
- Twist-off cap for easy resin refill with available pre-sized Sentry resin refill packets
- No PVC; wetted materials will not leach chlorides or plasticizers
Location of Steam Sample Tap Point
Samples must be taken from locations that are representative of the water source, treatment plant, storage facilities, distribution network, points at which water is delivered to the consumer, and points of use. In selecting sampling points, each locality should be considered individually; however, the following general criteria are usually applicable:
Sampling points should be selected such that the samples taken are representative of the different sources from which water is obtained by the public or enters the system.
These points should include those that yield samples representative of the conditions at the most unfavourable sources or places in the supply system, particularly points of possible
contamination such as unprotected sources, loops, reservoirs, low-pressure zones, ends of the system, etc.
Sampling points should be uniformly distributed throughout a piped distribution system, taking population distribution into account; the number of sampling points should be proportional to the
number of links or branches.
The points chosen should generally yield samples that are representative of the system as a whole and of its main components.
Sampling points should be located in such a way that water can be sampled from reserve tanks and reservoirs, etc.
In systems with more than one water source, the locations of the sampling points should take account of the number of inhabitants served by each source.
There should be at least one sampling point directly after the clean-water outlet from each treatment plant.
Isokinetic Sampling Probes For Steam Applications
- EPRI Isokinetic Sampling Nozzles (Probes)
- ASME PTC 19.11 The specification requires a "isokinetic sample nozzle" for representative sampling of the specific two-phase saturated steam flow via sample ports drilled in the side of the nozzle facing the steam flow.
- Recommended for saturated steam in steam boiler and power plants, for superheated steam (only if particulates are measured), isokinetic sampling is normally not required for water samples.
- These nozzles meet also the requirements of ASTM Standards D1066 and D3370.
- The nozzles extract a representative isokinetic sample from a flow region removed from the pipe surface and at the average flow velocity of the sample fluid.
- This arrangement results in the withdrawal of the sample with representative concentrations of dissolved, suspended, and volatile constituents.
- An appropriate nozzle (probe) is designed for the desired sample flow and typical conditions of the sample fluid. When the flow velocity through the pipe changes, sample flow should be adjusted to maintain isokinetic sampling.
- Each Nozzle (probe) is designed with considerations of vortex shedding, resonance, vibration, erosion, and strength of the attachment to the pipe.
