Rosemount TGU 65 Tank Radar Gauge, Still Pipe Antenna

Rosemount TGU 65 Tank Radar Gauge with still pipe antenna for marine tanks

The Rosemount TGU 65 is a marine radar level gauge that fits inside a still pipe of 5 or 6 inches. It forms part of the Rosemount Cargo Monitoring System and is built for tankers and offshore installations, where tanks are narrow, decks are exposed and deposits can form. It works with 10 GHz FMCW radar and is intrinsically safe.

Seven Star LLC supplies the Rosemount TGU 65 in Oman and the GCC as an independent supplier in Muscat. The gauge exists in two versions, TGU 65C and TGU 65S, so please say which one your project needs.

TGU 65C and TGU 65S: the two versions

Rosemount TGU 65 technical specifications

Why the TGU 65 uses a low-loss mode in the still pipe

Radar waves in a still pipe travel in a special polarised, low-loss mode. This makes the TGU 65 much less sensitive to build-up and contamination on the pipe wall, which is the weakness of many still pipe gauges on crude and product tankers. Even so, the datasheet stresses that the inside of the pipe must be smooth and free of irregularities for the best result.

The principle is FMCW: the gauge emits a continuous sweep of frequencies, mixes the returned echo with the outgoing signal and obtains a low-frequency signal proportional to the distance to the liquid. Only the antenna is inside the tank and there are no moving parts, and the tank gauge electronics can be serviced and replaced while the tank is closed.

Still pipe and installation requirements for the TGU 65

• The still pipe and deck socket are normally yard supplied. The pipe must be vented to equalise liquid level with the tank.
• The pipe can be made from flanged segments joined by bolts, butt-welded segments, or segments welded with a sleeve. It is metallic, typically stainless or carbon steel.
• For tank ullage the pipe ends over the bottom of the tank; for draft measurement it enters the sea water through a yard-supplied sea valve.
• The housing flange suits JIS 5K-200, DN200, DN250 and, on the S version, ASME 8 in.

Where the TGU 65 fits in the Rosemount system and related parts

Each measuring channel has one digital bus connection to a Rosemount SCU 51 Supply and Communication Unit. Optional bus connections go to Rosemount TMU 51/53 temperature measuring units and the TGD 51 tank gauge display. The gauge is prepared for a second channel, either as redundant level or as an independent high-level or overfill alarm, and the order list offers one or two channels. For larger open tanks, the Rosemount TGU 68 with a parabolic antenna is the alternative, and for LNG tanks the Rosemount TGU 53 is used.

Selection checklist for the TGU 65

• Choose 65C or 65S according to the project and the options needed.
• Confirm the still pipe size (5 in. or 6 in.) and whether the pipe will be yard supplied.
• Choose one or two measuring channels, plus the vapor pressure sensor and test valve if required.
• Check the housing flange and the cable gland size.
• State the required explosion protection (ATEX/IECEx or INMETRO) and marine class approval.
• For the S version, decide on extended range, tag plate and certificates.

Installation, commissioning and maintenance of the TGU 65

Check the pipe bore and venting before fitting the gauge, then mount the housing on its flange with the fluorosilicone O-ring and route cables through the glands, using the correct size for each cable. Commission the channel through the SCU 51 and the cargo software, entering tank height and reference. Keep the antenna clean and examine the pipe interior at scheduled tank entries. The optional vapor pressure sensor test valve lets the sensor be tested and replaced without breaking tank integrity.

Seven Star LLC can quote spare parts if you send the gauge serial number and the original order details.

Typical applications of the TGU 65 in Oman and the GCC

Typical use is in slop tanks, residual tanks and sea water draft measurements aboard tankers, and on offshore platforms and floating units where narrow tanks leave no room for a larger antenna. The IP66/67 enclosure and -40 to +70 °C ambient rating cope with the heat and humidity of the Arabian Gulf and Sea of Oman, and shipyards and marine service providers in the region can use the gauge for repair, retrofit and new-build programmes.

Information to send with an RFQ for the TGU 65

• Version (TGU 65C or TGU 65S) and number of channels
• Tank type, height and still pipe diameter
• Flange standard and size
• Explosion protection and class society
• Options: vapor pressure, test valve, hose, certificates
• Quantity and delivery location

Documents and quotation

A manufacturer datasheet for the Rosemount TGU 65 is attached on this page, so you can check the model code, ratings and dimensions against your project documents before ordering.

To receive a quotation, send us the part number or the full model code from your nameplate, the quantity, and the delivery location. Seven Star LLC is an independent supplier in Muscat and replies with availability and lead time, and we confirm the details with you before anything is ordered.