Terminology in monolithic refractories: dry mixes of refractory aggregates with hydraulic binders that are placed and set in situ are called what?

Introduction / Context:
Monolithic refractories are supplied as mixes and installed without firing into brick shapes first. Understanding the correct terminology (mortar, cement, castable, gunning mix, ramming mix) is essential for specifying and installing linings.

Given Data / Assumptions:

• Dry mixes contain refractory aggregates and a hydraulic binder (often calcium aluminate cement).
• They are mixed with water on site and cast or vibrated into place.
• They set hydraulically, then are dried and heated to service.

Concept / Approach:
“Castables” are precisely the category of monolithics that are mixed with water and placed or cast into position, where hydraulic setting occurs before drying and heat-up. “Refractory cement” refers specifically to the binder, not the whole composition. “Mortars” are primarily thin-bedded joining materials for bricks, with different particle size distribution and workability; they are not the same as structural castables.

Step-by-Step Solution:
Identify the definition: dry refractory aggregate + hydraulic binder placed wet in situ.Match to industry term: “castable”.Differentiate from mortars (jointing) and cements (binders only).

Verification / Alternative check:
Product data sheets and installation manuals consistently classify these as “refractory castables,” with subclasses like conventional, low-cement, ultra-low-cement, and no-cement sol-bonded systems.

Why Other Options Are Wrong:
Mortars: intended for brick joints.Cements: only the binder component.None of these: incorrect because “castables” is the standard term.

Common Pitfalls:
Calling any dry bagged refractory a “cement”; always distinguish the complete castable from the binder it contains.

Final Answer:
Castables