BIRKOSIT for Steam and Gas Turbine Parting-Plane Sealing

The parting plane of a turbine casing is one of the most demanding sealing joints in industrial use. BIRKOSIT — 900°C, 250 bar, permanently elastic, 10-year guaranteed — is formulated for exactly this joint. Available from Project Sales Corp for Indian customers.

A steam turbine parting plane is a precision-machined metal-to-metal joint that must remain absolutely sealed under temperatures up to 550°C or above at the steam path, internal pressures of 10–250 bar or higher, constant vibration, and thermal cycling through every start-stop sequence over a service life measured in decades. The sealing compound applied to this joint during overhaul must tolerate all of these conditions simultaneously — and must remain removable at the next overhaul without damaging the machined surface.

BIRKOSIT is rated to 900°C and 250 bar on butt joints, 450 bar on flanges, and 550 bar on screw joints. It does not cure — which means it never becomes brittle, never cracks under thermal cycling, and never forms a rigid bond that fractures and creates leak paths. Project Sales Corp stocks and supplies BIRKOSIT for customers and applications within India.

Why Non-Curing Is Critical for Turbine Parting Planes

Conventional sealants and many industrial pastes cure to a hard, rigid film after application. On a turbine parting plane, this is a failure mode waiting to happen. Every start-stop cycle generates temperature gradients across the casing — from cold ambient to full operating temperature — and the resulting differential thermal expansion between casing sections creates relative movement at the joint face. A brittle, cured sealant film cracks at the first thermal cycle. A permanently elastic compound like BIRKOSIT accommodates this movement and maintains its sealing film continuously.

There is also no shrinkage, no void formation, and no solvent release during or after assembly. The sealing film thickness at assembly is the sealing film thickness in operation. Steam cannot penetrate a continuously elastic film the way it can penetrate a voided or cracked cured sealant.

Application Procedure

Gas Turbine Applications

Gas turbines present the most extreme version of the turbine parting-plane sealing requirement. Combustion casing temperatures and the zero-tolerance for any leakage path — combustion gases leaking through a parting plane represent both a safety risk and a direct efficiency loss — make BIRKOSIT's 900°C temperature resistance and permanent elasticity the appropriate specification. The same product covers compressor casing parting planes in the gas turbine, where temperatures are lower but pressure and vibration loads are equally demanding.

Surface Damage Limit — When to Switch to FILLING

BIRKOSIT is designed for sound, precision-machined sealing surfaces with surface damage not exceeding 0.2 mm. If inspection of the parting plane reveals damage deeper than 0.2 mm — pitting, fretting, erosion cavities — BIRKOSIT is not the correct product for that joint. The FILLING product family (FILLING 1000 for up to 0.5 mm damage, FILLING 2000 for up to 1.0 mm) is the correct specification. BIRKOSIT and FILLING products must not be used together on the same joint.