Yes. Insulating bare pipes, valves and flanges reduces heat loss, which means the boiler or furnace burns less fuel. Less fuel = fewer direct CO₂ emissions = lower Scope 1. A typical plant saves 0.5–3 t CO₂ per m² of insulation added per year depending on pipe temperature and fuel type.
From our guide: How Insulation Reduces Scope 1 Emissions — full context, charts and sources there.