How To Measure Oil Casing Length?

According to the different requirements of the oil casing production process, the oil casing length measurement system also has a variety of measurement methods. So how to measure the length of oil casing? Today, Union Steel Industry will briefly introduce three methods of oil casing length measurement.

1. Grating ruler length measurement

The basic principle is to install two fixed-length grating rulers on the outside of the oil casing. The rod cylinder is used to drive the grating scale near both ends of the oil casing. The length of oil casing is measured using the phenomenon of light interference.

It has the characteristics of high precision. However, grating rulers are expensive, difficult to maintain, and sensitive to dust and site vibration.

2. Camera length measurement

Camera length measurement is achieved through image processing. The principle is to install a series of equidistant photoelectric switches on one section of the oil and casing conveying drum, and add a light source and camera to another section. When the oil casing passes through this area, the length of the oil casing can be determined based on the photoelectric switch and the position of the image captured by the camera on the screen.

Its characteristic is that it can realize online measurement, and the length data can be obtained when the elbow passes through the length measurement area without any interval. The disadvantage is that if a special light source is not used, the elbow will be disturbed by external light. After using a special light source, due to the high brightness at the bent end of the oil casing, the light reflection is very strong, which can easily cause reading errors.

3. Encoder length measurement

The principle is to install an encoder on the oil cylinder, use the oil cylinder to drive the oil casing to move on the drum, and install a series of equidistant photoelectric switches on the other side. When the oil cylinder pushes the elbow to contact the photoelectric switch, the distance moved by the oil cylinder can be calculated based on the recorded encoder reading, and thus the length of the elbow can be calculated.

It is worth noting that when measuring the length of the oil casing, the oil casing should be kept as horizontal as possible to reduce measurement errors. In addition, if the oil casing bends or bends in service, you may need to consider how to measure the length of the bend, or consider using a flexible measurement method, such as using a rope to measure the length along the curve of the oil casing. In certain applications, the length of the pipe connection may also need to be taken into consideration.