What is the purpose of this article?
Explain how Rheonics SRV viscometer and SRD density and viscosity meter can be installed under different use cases with the HAW-12G-xTK and HAW-12G-xTN accessories or with an appropriately machined interface.
What products are involved?
Rheonics SRV viscometer and SRD density and viscosity meter, as well as HAW-12G-xTK accessories.

TABLE OF CONTENTS

Introduction

Rheonics HAW-12G-xTK and HAW-12G-xTN accessories are hygienic adapter weldolets for the SRV and SRD sensors with 1/2” G thread (-X1-12G). These weldolets are designed for a flush installation in thin and thick walls (approximately ≥10 mm for thick walls) while ensuring the sensing element is fully immersed in the fluid.


Two variants are available for different types of seals. The HAW-12G-Mxx has a metal-to-metal seal while the HAW-12G-Oxx has a Ø15.1×1.6mm O-Ring seal.


Rheonics xTK weldolet accessory for thick walls

Figure 1: Rheonics xTK weldolet accessory for thick walls.


Use cases

Thin-walled tank

Thin-walled tanks are commonly used in several industries for low-pressure applications. These are typically seen in the chemical, food and beverage, and medical industry in both mixing and storage tanks. The HAW-12G-xTN is Rheonics' solution for thin-walled vessels, allowing the installation of SRV or SRD sensor probes.


Thin-walled aboveground storage tanks

Figure 2: Thin-walled aboveground storage tanks


Thick-walled tank

Thick-walled tanks or vessels are also fairly common, especially amongst higher-pressure applications in industries such as oil & gas, power generation, and the medical and pharmaceutical industries. Added to this, thick walls are also present in jacketed tanks where fluid needs to be thermally isolated, or required to maintain a certain temperature. In the case of jacketed tanks or thick-walled vessels, the HAW-12G-xTK can be welded on a wall or bottom as a port for the SRx-X1-12G.


Double-jacketed tank for mixing operations

Figure 3: Double-jacketed tank for mixing operations


Inline

In the cases where density and viscosity is to be monitored in line, the HAW-12G weldolets can be used on pipes for perpendicular sensor installation. Ultimately, the accessory variant selected depends entirely on the pipe schedule or the pressure of the application. The use of the HAW-12G accessories is generally recommended by Rheonics as it helps ensure proper insertion of the probe’s sensing element into the fluid. 

Installation guidelines using Pre-machined HAW adapters

The recommendations for the installation of an HAW adapter depend on the accessory type and the thickness of the wall. Below are the considerations that must be taken when installing these adapters in both thin and thick-walled vessels. In general, when installing these, the weep holes must always be oriented such that they sit at the lowest point possible. 


HAW-12G for thin walls 

The HAW-12G-xTN is Rheonics' accessory for using the SR-X1-G12 sensor probes in thin walls. This accessory can be installed in walls of up to 1.5mm and ensures a proper insertion of the sensing element into the fluid.


Installation of SRV and SRD 12G with HAW-12G in a thin wall

Figure 4: Installation of SRV and SRD 12G with HAW-12G in a thin wall


HAW-12G for thick walls (up to 10 mm) 

The HAW-12G-xTK is Rheonics' accessory for using the SR-X1-G12 sensor probes in thicker walls. This accessory can be installed in walls of up to 10 mm and ensures a proper insertion of the sensing element into the fluid.


Installation of SRV and SRD 12G with HAW-12G in a thick wall

Figure 5: Installation of SRV and SRD 12G with HAW-12G in a thick wall

Conical interfaces for compression sealing - Machining and Install Guideline

Alternatively, the HAW conical interface can be machined directly onto a tank. This can be beneficial when a tank is commissioned, providing a port-specific for the SR-X1-G12 sensor probe. If this is the desired scenario, two sealing alternatives are possible; O-ring sealing and metal-to-metal sealing.


Indifferent from the seal selected, any wall thicker than 17.3 mm will require a conical opening to be machined into the tank wall to allow for the sensor probe’s back end to sit. An example of this can be seen in Figure 6 or in this provided drawing.


Tank wall with thickness over 17 mm showing the machined conical opening necessary for the back end of the probe.

Figure 6: Tank wall with thickness over 17 mm showing the machined conical opening necessary for the back end of the probe.


If machining is desired, the following drawings must be used, paying close attention to the tolerances specified.


Machined interfaces with O-ring sealing

An O-ring seal interface is especially good for applications that involve vibrations or corrosive fluids. With the use of this port, an adequate O-ring that withstands the conditions necessary can be selected. It is important for the tolerances and dimensions present in the following drawing to be respected in order to achieve an adequate seal.


HAW Conical Interface drawing with dimensions and tolerances for SR-X1-G12 sensor probes with O-ring sealing

Figure 7: HAW Conical Interface drawing with dimensions and tolerances for SR-X1-G12 sensor probes with O-ring sealing


Machining interface with conical surface direct metal-metal sealing

If the application requires operation under higher temperatures or pressures, metal-to-metal seals are recommended.  It is important for the tolerances and dimensions present in the following drawing to be respected in order to achieve an adequate seal.


Figure 8: HAW Conical Interface drawing with dimensions and tolerances for SR-X1-G12 sensor probes with metal-to-metal sealing


[1]. SRV and SRD Suitable Installations

[2]. SRV-X1-12G: G 1/2"

[3]. SRD-X1-12G: G1/2"