Insulator Spacing

A pipeline industry “rule of thumb” is that insulators should be spaced from 8 to 12 feet apart. Some pipeline companies have achieved excellent results by positioning two of the insulators at each end of the casing and then spacing the insulators 4 to 6 feet apart.

Model 60™ Physical Properties

Dielectric strength
(ASTM D-149)
step-by-step method
450 – 500 volts/mil

Compressive strength
(ASTM D-695)
3200 psi

Flexural yield strength

(ASTM D-790) 1000 psi

Tensile strength
(ASTM D-638, D-651)
3100 – 5500 psi

Impact strength
(ASTM D-256)
4.0 ft. lbs. / in. of notch

Water absorption
(ASTM D-570) <0.01%

Max. continuous operating temp.
225°F

 

Casing Insulator Model 60 for Electrical Isolation

Casing Insulator Model 60 by Maloney Tech is precision manufactured by injection molding. The material used is virgin High-Density Polyethylene. For carrier pipe sizes up to 12 inches, the insulators are fabricated in two sections. For sizes 14 inches and larger, the insulators are fabricated in combinations of 2 pi and 4 pi sections. With the insulators properly installed on the carrier pipe, the carrier can easily be pulled into the casing due to the low coefficient of friction of the polyethylene material.

Model 60 insulators resist damage during installation of the carrier pipe because of the high impact strength and excellent abrasion resistance of the polyethylene. Shallow, molded grooves on the inner surfaces of the insulator sections prevent slippage and minimize cold flow of the coating on the carrier pipe. Electric current loss is negligible and cathodic protection is unimpaired due to the high insulating value and low water absorption of the polyethylene. Model 60 insulators are available in sizes 2 through 48 inches. The standard runner height is 1 inch. For insulators 14 inches and larger, 1-1/2-inch runners are available upon request.

Model 60™ Dimensions & Specifications (Sized for Steel Pipe O.D.)