What is the purpose of this article?
This article shows the alternatives and guidelines for the installation of Rheonics SRV and SRD in tank roofs or lids.
What products are involved?
SRV - Inline Viscosity Meter and SRD - Inline Density and Viscosity Meter, and installation accessoriesTABLE OF CONTENTS
Measuring density and viscosity in a tank
- Installation considerations for Rheonics viscometer and density meter in a tank
- General guidelines
- Process connections used for mounting viscometer and density meters in tanks
- Protecting your sensor
- Rheonics viscometer and density meter installation in open tanks
- Stationary / fixed mixing open tank
- Stationary mixing arms with rotating tanks
Viscometer and density meter installation options/positions for closed tanks
Measuring density and viscosity in a tank
In industrial processes, measuring viscosity and density within tanks is crucial for ensuring operational efficiency, quality, and safety. Viscosity and density are representative of how substances mix, pump, and process, and are commonly used to monitor uniformity, consistency, formulation, and ultimately the quality of the final product. By closely monitoring these parameters, industries can achieve better control over their processes. Whether it's a mixing or a storage vessel, monitoring these variables helps reduce waste and increases the reliability and effectiveness of operations.
Rheonics offers a variety of alternatives when it comes to measuring viscosity and density in tanks. This article will explore the alternatives and give guidelines on how the SRV and SRD. can be installed in your tank's lid or roof.
Installation considerations for Rheonics viscometer and density meter in a tank
General guidelines
In general, the following considerations must be taken for proper sensor probe installation:
Shafts or rotating blades must not hit the sensor probe
Shafts or rotating blades must not interfere with the sensing areas of the probes.
The sensor must be ordered so that after installation, the sensing area sits below the minimum fluid level in the tank. This way, the sensing element will always be immersed in the fluid.
Figure 1: SR-Type X8 variant installed in a tank lid with proper insertion length. The sensing element sits below the minimum fluid level.
Note: The Rheonics support team will be happy to assist you in finding the adequate insertion length for your application. |
| Warning: For mixing tanks, special attention must be paid to the fluid's viscosity and mixing speed when insertion lengths exceed 500 mm. High viscosity levels or considerably high speeds can create strong bending forces near the installation point, ultimately bending the probe. |
Warning: The SRD is more sensitive to noise, therefore if the readings obtained with an SRV are already noisy, it is not recommended to switch to the SRD when density readings are desired. Noise is usually a product of bubbly fluids, low mixing speeds, or large suspended particles. |
Variant selection
Rheonics offers viscosity and density meters in a variety of presentations. You can see a comparison of these alternatives in the image below:
Figure 2: Variants offered by Rheonics for installation in tank roofs or lids. Left to right: SRV-X1 with TMA 34N, SRV-X5 (30 mm body), SRV-X6 (19 mm body), SRV-X8 (bottom)
Figure 3: Comparison of variants offered by Rheonics for installation in tank roofs or lids. Left to right: SRV-X1 with TMA 34N, SRV-X5 (30 mm body), SRV-X6 (19 mm body), SRV-X8 (bottom).
In short, the variants offered for installations at the top of a tank are:
X1 Probe with TMA 34N
The SRV-X1/SRD-X1 is our flagship sensor probe variant. It can be installed in a tank with the TMA 34N accessory. This accessory allows the use of a pipe of custom length, requiring only an NPT 3/4” thread on one side. The TMA also protects the sensing element from collisions against moving elements in the bank or during installation.
Figure 4: TMA-34N installed in an SRV (bottom) and SRD (top)
Common use cases include:
Slurries - Offers robust protection
It is good for open tanks
Not suited for hygienic applications
X5 Probe - Long insertion probe
The SRV-X5/SRD-X5 is our long insertion probe variant. This probe can be ordered with a customized insertion length and process connection, helping submerge the sensing element properly in the fluid.
Figure 5: SRD-X5 installed in a closed tank using a flange process connection
Common use cases include:
Hermetically sealed single-body probe and hygienic design available for sanitary applications
Protection cage available for applications with suspended particles or hand cleaning
Good for pressure vessels up to 100 bar
X6 Probe - Slimline probe
The SRV-X6/SRD-X6 variant is similar to the X5 with the main difference being its slimmer profile. The reduced body diameter of 19 mm allows it to fit in thinner ports and ensures minimal interference with moving parts.
Figure 5: SRV-X6 installed in a small reactor reactor port using an Ingold process connection
Common use cases include:
Hermetically sealed single-body probe and hygienic design available for sanitary applications
Good for tanks with small ports
Suited for work in small reactors and glass reactors
X8 Probe - Teletube Ultra-long insertion probe
The SRV-X8/SRD-X8 or Teletube variant comprises a modular design for special applications recommended by Rheonics. Its modular style requires threaded sections that seal with O-rings. Assembly is done by customer on site following Rheonics Installation guidelines. This modular design makes transport, testing, extension, assembly, and disassembly easy.
Figure 6: SRV-X8 installed in a closed tank using a flanged process connection.
Common use cases include:
It is good for big tanks where large insertion lengths are required
Not suited for hygienic applications
Includes threads with O-Rings seals in contact with the fluid.
The specifications of each variant are explored in the table below.
Table 1: Specifications of the SRV and SRD sensor variants offered by Rheonics
Property | -X1 Probe (with TMA 34N) | -X5 Probe | -X6 Probe | -X8 Probe |
Maximum Pressure | Accessory not designed for high-pressure applications. The sensor probe can withstand 500 bar. | Dependant of process connection. The sensor probe can withstand 100 bar (1500 psi) | Dependant of process connection. The sensor probe can withstand 500 bar (7500 psi) | Low Pressure (around ambient) |
Temperature range* | -30°C to 90°C 150°C can be achieved with high-temperature cable and O-rings (FKM or FFKM) | -40°C up to 285°C | -40°C up to 285°C | -30°C to 90°C For temperatures above 80-90°C and up to 150°C, use X8-HT |
Maximum probe length | Variable and defined by the custom tube | Variable and defined in custom order Up to 1000 mm. For longer insertions contact Rheonics Support Team | Up to 450 mm | Variable and defined in custom order |
Hygienic certification | Not available | 3-A and EHEDG versions are available | Not available | |
EX Proof certification | ATEX, IECEx, and JPEx certificates are available | |||
*Ranges indicated are maximum ranges available Max. rating is defined in customer RFQ
Process connections used for mounting viscometer and density meters in tanks
Rheonics offers solutions that follow industry standards. In this way, both the SRD and SRV can be installed in common or custom process connections. The table below shows what process connections are available for each variant.
Table 2: Commonly used installation methods for SRV and SRD sensors in tanks
Property | -X1 Probe (with TMA) | -X5 Probe | -X6 Probe | -X8 Probe |
Common methods of fixing the sensor probe to a tank or structure (mixing arm) | Clamp for 3/4” NPT pipe Direct connection using threaded 3/4” NPT pipe Pipe can also have a custom process connection defined and provided by the customer | Can be ordered with any welded process connection as long as the ID of the mating port is > 30 mm Can be ordered with an APC - Adjustable Process Connector as long as the ID of the mating port is > 42.2 mm and the process connection is less than 1” thick. Can be ordered without any process connections. | Can be ordered with any welded process connection as long as the ID of the mating port is > 19 mm Can be ordered with a compression fitting Can be ordered without an process connection | Can be ordered with any welded process connection as long as the ID of the mating port is > 30 mm Can be ordered with an APC - Adjustable Process Connector as long as the ID of the mating port is > 42.2 mm and the process connection is less than 1” thick. |
Protecting your sensor
When installing Rheonics' sensors in tank roofs or lids it is important to maintain the sensing element and connection port and cable safe. The sensing element is the most important, for this reason, Rheonics has developed protective cages and sleeves that help prevent collision at the sensing element during installation and the tank’s manual cleaning. These accessories can also be used to protect the sensing element from undissolved particles or suspended solids in the fluid, however, this is not their main purpose. Regarding cables and connector protection, learn more about them here. Below is a list of the available protective accessories for installation in tank roofs or lids.
Table 3: Protective accessories available for each SRV and SRD sensor variant offered by Rheonics
Installation option in a closed tank | Rheonics Accessories and Alternatives |
-X1 Probe with TMA | The TMA 34N - Tank Mount Adapter already works as a protecting cage for the probe’s sensing element |
-X5 Probe | IMS-SR - Impact Shield for SR-Sensors (for cable connection) / SPS-SRX - Protective Sleeve (for sensing element) |
-X6 Probe | IMS-SR - Impact Shield for SR-Sensors (for cable connection) / SPS-SRX - Protective Sleeve (for sensing element) |
-X8 Probe | The SRV-X8 Probe already comes with protection for the cable / Direct connection to SME-TRD/TR |
Rheonics viscometer and density meter installation in open tanks
For open tanks, the user should determine how the probe will be attached or fixed to avoid movements during measurement. This can be achieved by using fixed metal sheets, brackets, or custom adapters that match the process connection or variant selected. Rheonics' Support Team will be happy to assist you in determining the best way of securely attaching the sensor probe to the open tank.
Stationary / fixed mixing open tank
For stationary or permanently installed open tanks, the SR-Type sensors can be installed in numerous ways. Since these vessels' process conditions allow it (temperatures and pressures near ambient), customers usually opt to use the X1 as the most cost-effective alternative. This is a common case for slurry tanks or drums. Rheoniscs has developed Slurry Track, which is an online monitor and controller of ceramic slurry density and viscosity. Read more about it here.
Figure 7: Slurry Track solution developed by Rheonics for slurry open tanks and drums.
Stationary mixing arms with rotating tanks
Tanks may also be changed frequently making installation in the tank not recommended. These usually pass through a fixed mixing station as is common in the paints and coating industry. Here, the sensor probe can be fixed to the mixing arm’s structure. This can be done in many ways and is left to the customer's convenience. An example of this can be seen in the image below.
Figure 8: Rheonics X8 - Teletube installed in a mixing station
Ultimately, the customer can opt for the process connection of their choice (NPT, Tri-Clamp, Flange, etc.) and develop a custom adapter that allows installation in the mixing arm’s structure. The sensor should not be installed in the mixing arm itself (moving shaft).
Viscometer and density meter installation options/positions for closed tanks
Here, the same installation principles as when installing in open vessels apply, however, temperature and pressure may go higher than in open tanks. For pressure ratings and temperatures supported, please refer to Table 1. As a first step, customers should always determine if any of the explored variants fit an already existing port in the tank’s lid or roof.
In general, either the X5 or X8 are recommended. Thanks to their customizable insertion length, they help place the sensing element into the fluid in case the tank is tall or has a varying fluid level. The main difference between the X5 and X8 is their ease of installation. Installing long sensors may become complicated, here, the X8 has the added benefit of modularity, allowing it to be assembled on-site. Regarding the X6, this variant is ideal for tanks with small ports (an inner diameter smaller than 31 mm and bigger than 22mm).