Casing Insulator



Casing Insulator is a patented series of polyethylene insulators that are universally applicable in the installation of pipelines when the carrier pipe runs inside a casing. They are used to support the coated pipe within a tubular casing, to electrically insulate the pipe from the tubular casing and to prevent damage to the coated surface of the pipe when the pipe is installed within the casing.



When the pipeline is buried in the ground, for instance, at underground road, river, railway and highway crossings, the pipeline is generally further protected by being enclosed within a tubular casing. The pipeline is supported within the casing by a Casing Insulator. The Casing Insulator, in addition to its supportive function, electrically insulates the pipeline from the casing. This insulative function is necessary for the cathodic protection of the pipeline, and also, for preventing electric current loss when the pipeline is used as a conduit for electrical cables. Furthermore, the Casing Insulator prevents damage to the outer coated surface of the pipeline when the pipeline is drawn through the casing during installation.



Casing Insulator is a high-density, polyethylene product, injection molded to provide low cost insulator of highest quality. It offers the following general features:


(i)       Easy Installation: Minimal coefficient of friction of the polyethylene material allows the carrier pipe to be more easily pulled through the casing thus helping in easy installation of the carrier pipe within the casing.

(ii)      Cathodic Protection: Insulating properties like excellent dielectric resistance and low moisture absorption of the polyethylene material used ensures of meting with all the requirements of cathodic protection and yielding minimal electric current loss.

(iii)    Coating Protection: High impact strength and excellent abrasion resistance of the polyethylene material prevents damage to the coated surface of the pipe when the pipe is installed within the casing and ensures long time resistance from chemical corrode minimizing cold flow of the coating on the carrier pipe.

(iv)     Concentricity: Wide range of skid heights ensures the concentricity of the carrier pipe in the casing.



Our Casing Insulator offers some specific features over traditional casing insulators.


(i)       Excellent Design: Designed and manufactured under the guidance of experts and engineers from Tsinghua University, Beijing University of Chemical Technology and China Petroleum Pipeline Bureau, Our Pipeline Casing Insulator are ensured of having highest quality, best design and excellent performance level meeting or exceeding industry standards.

(ii)      Excellent Fastness: Reinforcement measures such as steel straps are used to fasten insulators firmly on the carrier pipe preventing slippage or looseness of the insulators and avoiding them from sliding along the carrier pipe.

(iii)    Enhanced Coating Protection: On the inner wall of the Insulator, a rubber plate is affixed to enhance the coating protection of the pipeline and insuring the quality of the product as well as speeding up the construction process.

(iv)     Quick Installation: Electric Wrench is supplied for quick installation, speeding up the construction process further and saving costs.



The general “rule of thumb” of the pipeline industry is to space Casing Insulators 8 to 15 ft apart. The recommended spacing for our Casing Insulator is to position two of the insulators at each end of the casing and then space the insulators 6 to 8 ft apart. Actual spacing may vary depending on local regulations and design specifications.



Casing Insulator is designed for use in most carrier pipes within casings and suitable for all pipe diameters from 38mm upwards. Wide range of skid heights is available to suit specific requirements. We also design and manufacture Insulators as per customer’s specific requirements.