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Oilfield experts need appropriate instrumentation to keep the operations going at a steady pace. Weight indicators are a crucial part of the mechanical structure that allows drillers to monitor the inefficiencies in the load during the drilling operation.

The weight puts the wire rope in tension and thus needs to be supervised closely at all times. Failure to maintain a standard safe weight can result in dangerous accidents that cause harm to the people, infrastructure, and oil production.

Here’s all you need to know about the weight indicators.

What is the weight indicator like?

The weight indicators used in the oil and gas industry are built on a hydraulic system. A hydraulic gauge is attached to the dead line of the drilling rope, and that measures the weight. As the load tugs at the line, hydraulic fluid forces through the instrument, give the indicator an accurate reading of the force i.e., the weight.

The reading includes the mass of the drilling cable, traveling blocks, and tension on the rope. Drillers must always account for zero error by taking a reading before attaching any weight to the drill string. Once the zero offset is adjusted, accurate readings can be recorded.

How is the weight of interest calculated?

As mentioned earlier, the recorded weight reflects the pull force of the drill pipe and the bottom hole assembly. However, drillers are only interested in the latter. One way to calculate that is to take the difference of both weights and assume that the answer is the bottom weight.

A more accurate way is to use weight indicators with a second dial that automatically sets to zero when the drill string is free and unattached to a weight. When the bottom weight adds to the reading, the difference translates into the readings changing between dials and the additional weight giving an exact reading on the second dial. That way, the reading on the second dial is the weight of interest that drillers need.

What factors affect weight?

The weight indicator is the primary instrument used to monitor the downhole tools and their functions. Since it’s used to record the weight of the coiled tubing string or slickline string in a wellbore, there are several extraneous factors at play. These include fluid density which in turn affects the readings of wellhead pressure and buoyancy.

If you’re looking for affordable but high-quality oilfield instrumentation, including weight indicators, look no further.

Contact Instruments is a leading manufacturer of OEM instrumentation in Canada with a production facility in Leduc, Alberta. We supply drilling equipment such as mud pressure gauges, custom cables, or clipper weight indicators for Canadian and American oil companies at affordable rates.

Check out our full range or call at 780-955-8998 for more information.