Sierra InnovaMass 241S Insertion Multivariable Mass Vortex Flow Meter

Overview

The Sierra InnovaMass 241S is the insertion version of Sierra’s multivariable mass vortex flow meter. A probe passes through a single two-inch process connection into a pipe of 2 inch diameter or greater, and measures mass flow rate, volumetric flow rate, temperature, pressure and density together. The manufacturer notes that the 241S has emerged as the proven instrument of choice in geothermal steam applications around the world, and it suits saturated or superheated steam and any gas or liquid compatible with 316L stainless steel.

Large steam mains, flare and fuel gas headers and cooling water lines in Oman’s refineries, power stations and utilities are costly to cut and re-pipe, so an insertion meter that can be fitted through one tapping is attractive. Seven Star LLC supplies the Sierra InnovaMass 241S with engineering support in Muscat, together with the retractor, flange and probe seal options that match each line.

Insertion Vortex Principle

The 241S carries a vortex shedding sensor at the tip of an insertion probe. When the probe is placed in the pipe, vortices shed from the bluff body at a rate related to the local velocity, and the meter integrates that signal with the pipe diameter to find the flow through the whole pipe. A temperature sensor and a pressure transducer in the same probe allow the electronics to calculate density and mass flow using real gas, ideal gas and AGA-8 equations, so the Sierra InnovaMass 241S reports total mass flow through the pipe as one number.

Accuracies are stated for total mass flow through the pipe: plus or minus 1.5 percent of rate for liquids and plus or minus 2.0 percent for gas and steam over a nominal 30:1 range, with volumetric accuracy of 1.2 percent for liquids and 1.5 percent for gas and steam. Smart electronics correct for low flow down to a Reynolds number of 5,000, and the meter must be mounted perpendicular to the pipe centerline within plus or minus 5 degrees.

Engineering Design of the Sierra InnovaMass 241S

The probe is 316L stainless steel with a Teflon packing gland below 500 °F (260 °C) and a graphite packing gland above that temperature. Process connections include a two-inch male NPT and two-inch flanges in 150, 300, 600 and 900 lb ratings. Compression fitting probe seals carry ratings of up to ANSI 900 lb, while packing gland seals are limited to 50 psig unless a retractor is fitted. Removable retractors with packing gland seals are rated up to ANSI 300 lb, and permanent retractors up to ANSI 900 lb.

The retractor makes the Sierra InnovaMass 241S hot-tappable, so the meter can be installed or removed under line pressure without shutting down the process. The electronics are in an explosion-proof NEMA 4X, IP66 enclosure with a 2 x 16 LCD and six push buttons operated through the glass. Power, outputs and communications match the 240S, with loop-powered, multiparameter DC or AC supply options, HART as standard, and Modbus and BACnet options. Pressure transducer ranges run from 30 to 1,500 psia.

Key Features

The Sierra InnovaMass 241S offers these capabilities:

• Insertion design for pipes of 2 inch and greater that requires only a single process connection.
• Optional hot-tap retractor for installation and removal without a process shutdown.
• Mass flow, volumetric flow, temperature, pressure and density from one probe.
• Fluid temperature up to 500 °F (260 °C) as standard and up to 750 °F (400 °C) with the high-temperature sensor.
• Rangeability up to 100:1 with smart DSP electronics extending low flow to a Reynolds number of 5,000.
• Energy (BTU) monitoring for steam and other utilities.
• FM, FMC, ATEX and IECEx approvals for hazardous areas, with CSA, CRN and CE marks.
• Field configuration through six push buttons or a magnet, without opening the explosion-proof enclosure.

Industrial Applications

The Sierra InnovaMass 241S has become a standard choice for geothermal and process steam, and it also measures natural gas, compressed air, flare gas and water in large pipes. In the Sultanate of Oman the insertion design suits steam headers at power and desalination plants, fuel gas and flare headers at oil and gas facilities, and large utility mains in the industrial zones at Sohar and Salalah where cutting a flanged spool into the line would be disruptive.

The insertion probe must be installed with the correct immersion depth and straight pipe length, and Sierra offers a sizing program for typical flow ranges that depend on fluid and pipe size. Seven Star LLC supplies the Sierra InnovaMass 241S together with steam and flow instruments such as the Spirax Sarco TVA steam target flowmeter, the Spirax Sarco TFA steam target flowmeter and the Rosemount 8800D vortex flowmeter, so steam metering can be specified from one source.

Technical Specifications

The table lists data from the manufacturer datasheet for the Sierra InnovaMass 241S. Confirm the probe seal, process connection and options against the ordering chart.

Request a Quote for Sierra InnovaMass 241S

Send an RFQ for the Sierra InnovaMass 241S to the Seven Star LLC instrumentation team in Muscat with the fluid, pipe size and schedule, flow, pressure and temperature range, and whether hot-tap installation is needed. We will confirm the probe seal, retractor and flange options, arrange supply to Oman and the GCC, and include the manufacturer’s Sierra InnovaMass 241S datasheet with the quotation for your engineers to review.