Type D Insulation Gasket (Ring Joint)

At Kriloha Ltd., we recognize that in high-pressure environments, there is no room for “approximate” sealing. When a flange is rated for 5,000 or 10,000 PSI, the insulation must be as rugged as the steel it separates. The Kriloha Type D Insulation Gasket is our engineered answer for “Extreme-Pressure” isolation. As a premier global provider of high-integrity seals, Kriloha Gaskets has mastered the Precision Machining required to produce phenolic and G-10 rings that seat perfectly into API-standard grooves.

The engineering of our Type D series is based on Compressive Stamina. Unlike flat gaskets, an RTJ insulation ring must handle massive point-loads without cracking or deforming. At Kriloha, we utilize a specialized high-density lamination process to ensure our materials have the necessary “hoop strength” to resist internal pressure while providing a total dielectric break. Every Kriloha Type D ring is inspected for dimensional accuracy to ensure a “Metal-to-Phenolic-to-Metal” fit that stops current and fluid alike.

Manufacturing these kits at Kriloha involves strict Dielectric Breakdown Testing. We ensure that even under the intense mechanical loads of a bolted RTJ joint, the material retains its Kilovolt (kV) resistance. Whether you are isolating a high-pressure subsea injection line or a refinery reactor, Kriloha Type D Insulation Gaskets provide the mechanical invincibility and electrical agility your facility demands. By choosing Kriloha Ltd., you are investing in a “High-Integrity” technology that secures your most critical high-pressure assets against the threat of corrosion.

Primary Use Cases

High-Pressure Oil & Gas Wellheads: The primary choice for isolating Christmas trees and wellhead assemblies from the flowline to manage cathodic protection currents.
Offshore Production Platforms: Used in high-pressure manifold systems where space is limited and RTJ flanges are mandatory for safety and leak prevention.
High-Pressure Transmission Lines: Isolating segments of gas pipelines operating at extreme pressures where standard flat gaskets cannot be used.
Refinery High-Pressure Steam & Hydrocarbons: Providing electrical isolation for heat exchangers and vessels operating under high thermal and mechanical stress.
Sour Service Environments: Utilizing the chemical stability of reinforced phenolic to prevent galvanic corrosion in the presence of H2S.

FAQs

Can I use a Type D gasket in a standard flat-face flange?

No. Type D gaskets are exclusively designed for flanges with a machined ring groove (RTJ). For flat or raised-face flanges, Kriloha recommends our Type E or Type F insulation sets.

Which is better: Oval or Octagonal profile?

Octagonal profiles are generally considered to have a higher sealing efficiency and are the modern standard for RTJ grooves. However, Kriloha provides Oval profiles for older equipment or specific engineering requirements.

What is the temperature limit for Type D Phenolic?

Standard Reinforced Phenolic is suitable for temperatures up to +120°C. For higher temperature RTJ isolation, Kriloha recommends our G-11 (Epoxy Glass) version, which handles up to +200°C.

How do I prevent the gasket from cracking during installation?

RTJ flanges must be perfectly aligned. Because phenolic and G-10 are less “forgiving” than metal rings, ensure the flanges are parallel and the bolts are tightened in a strict “star” pattern to the torque specifications provided by Kriloha.

Is a seal-filler available for Type D?

While the ring itself provides the seal, Kriloha can provide “BX” or “R” type rings with internal elastomeric seals (Viton or PTFE) for added security in “Searching-Gas” applications.