SLXAT87 – Tee 87º

Solinox SLXAT87 87-Degree Tee Technical Specification and Flow Dynamics

Navigating structural transitions within high-performance exhaust infrastructures requires components that preserve draft velocity while managing thermal stresses. The Solinox SLXAT87 87-degree tee serves as a critical junction component engineered specifically for complex double wall chimney systems. Designed to facilitate the transition from a horizontal breach to a vertical riser, this component eliminates the structural and aerodynamic vulnerabilities common to standard 90-degree branch connections. For mechanical engineers and HVAC professionals, the SLXAT87 provides a robust solution that complies with rigorous European performance and safety standards for an industrial steel chimney.

Why the 87-Degree Geometry Governs Chimney Systems Efficiency

In the engineering of comprehensive steel chimney systems, the connection point between the appliance breach and the vertical stack is highly susceptible to fluid resistance and condensation pooling. Standard 90-degree T-pieces create an abrupt perpendicular directional change that causes boundary layer separation, generating turbulence and localized backpressure.

The Solinox SLXAT87 resolves this through an exact 87-degree geometric branch angle. This design introduces a mandatory 3-degree pitch when the component is integrated into horizontal exhaust runs. This slope ensures that the system complies with gravity-fed drainage principles, forcing corrosive flue gas condensates to flow continuously toward designated drainage points rather than pooling within the branch joint. Simultaneously, the internal radius reduces the pressure drop coefficient across the junction, preserving the optimal natural or mechanical draft required for high-capacity industrial chimney operations.

Material Architecture and Performance Specifications

Every SLXAT87 tee is manufactured using advanced automated laser-welding processes to ensure gas-tight, pressure-resistant seams that remain stable under continuous thermal cycling.

• Inner Liner Material: High-grade AISI 316L stainless steel, specifically selected for its exceptional resistance to electrochemical corrosion induced by halogenated compounds and acidic condensates.
• Outer Jacket Material: Structural AISI 304 stainless steel, providing high mechanical strength, resistance to external atmospheric corrosion, and long-term aesthetic stability.
• Insulation Core: High-density, bio-soluble rockwool insulation with a uniform thickness of 25mm or 50mm, ensuring low outer skin temperatures and complete elimination of thermal bridging.
• Joint Mechanism: Precision-machined male-female coupling system secured via a heavy-duty locking band, maintaining structural integrity under positive pressure conditions up to 200 Pa.
• Thermal Rating: Fully certified for continuous operational exposure up to 600 degrees Celsius and tested to withstand temporary soot-fire shocks.

The Solinox Advantage in Double Wall Chimney Engineering

A primary failure point in conventional double skin chimney installations is the rigid constraint of the inner and outer metal layers. As high-temperature exhaust enters the double wall chimney, the inner liner undergoes rapid linear thermal expansion, while the outer jacket remains close to ambient temperature. If this differential movement is not accommodated, it causes severe mechanical stress, leading to joint deformation, cracked seams, and insulation degradation.

The Solinox double wall chimney design solves this problem by utilizing an independent floating inner wall configuration at the tee junction. The inner liner is permitted to expand and contract freely along its horizontal and vertical axes without transferring structural loads to the external jacket. Furthermore, the specialized insulation containment technique prevents the settling of rockwool fibers, ensuring that the thermal boundary remains completely uniform throughout the operational lifespan of the chimney systems.

Sizing and System Integration Parameters

The SLXAT87 tee is fully cross-compatible with the broader Solinox portfolio, including single wall chimney systems and dedicated pellet stove pipe configurations. When executing fluid dynamics calculations for an industrial chimney stack, mechanical designers must account for the equivalent pipe length of all fittings to determine total system friction loss. 

The aerodynamic optimization of the SLXAT87 results in a significantly lower equivalent length value than standard multi-segment welded tees, allowing engineers to minimize the overall height or diameter of the industrial steel chimney without risking draft degradation.