Positioning requirements and implementation methods when installing heating and thermal insulation riser sleeves

Specific positioning requirements and implementation methods when installing heating and thermal insulation riser sleeves

Concentricity of riser sleeve and casting

Requirements: The center of the riser sleeve needs to be strictly aligned with the center of the riser neck of the casting, and the deviation is usually controlled within ±1mm (the specific value is adjusted according to the size of the casting and process requirements).

Implementation method:

Use special positioning pins or positioning blocks to fix the position of the riser sleeve.

Pre-embed positioning marks (such as engraved lines and bosses) on the mold, and align the marks during installation.

Use three-dimensional measurement equipment (such as laser trackers) to assist positioning to ensure high accuracy.

Gap control between riser sleeve and riser neck

Requirements: The inner diameter of the riser sleeve and the outer diameter of the riser neck need to match. If the gap is too large, it will cause leakage of molten metal. If the gap is too small, it may hinder feeding. Generally, the gap is controlled within the range of 0.5-2mm.

Implementation method:

Select the riser sleeve of appropriate specifications according to the size of the riser neck.

Use sandpaper or a file to trim the surface of the riser neck to ensure it is round and flat.

Apply refractory paint to the inner wall of the riser sleeve to fill small gaps and prevent sand from adhering.

Verticality and inclination angle of riser sleeve

Requirements: The riser sleeve must be installed vertically (except for special processes). The inclination angle exceeding 5° may affect the feeding effect.

Implementation method:

Use a level or angle measuring instrument to check the verticality of the riser sleeve.

Design limiting structures (such as baffles and slots) on the casting mold to prevent the riser sleeve from tilting.

The relative position of multiple riser sleeves

Requirements: When a casting requires feeding of multiple riser sleeves, each riser sleeve must be symmetrically distributed to ensure balanced feeding pressure.

Implementation method:

Optimize the layout of the riser sleeve through CAD simulation to ensure uniform coverage of hot spots.

Use templates or tooling to install multiple riser sleeves simultaneously to ensure positional consistency.