NBN ISO 18886:2021

This International Standard specifies the procedures for the preparation of test pieces from refractory
materials by wet gunning at ambient temperatures. The test pieces are for the determination of
properties on wet-gunned products prepared under either “standard conditions” (as required for
quality assurance or product development) or “site conditions”. In the case of “site conditions”, the
purpose of the testing is to establish the properties pertaining to a given installation or a given set of
installation conditions. In this case, the gunned panel is obtained during the on-site installation. Such
parameters as activator addition (type, amount, method of addition), conveying pressure and curing
conditions (temperature, orientation of the panel) applying during the preparation of the panel are as
near as possible to the same parameters pertaining to the site installation.
This procedure applies to refractory materials that can be transported through a gunning hose after
having been mixed with the total water requirement for material placement. The consistency of these
materials (see 7.5) is typically such that they would be suitable for placement by casting were they not
to be transported through the gunning hose and applied by spraying.
Refractory materials that are pneumatically conveyed in the “dry” state through a gunning hose, even
after mixing with a portion of the total water requirement (the bulk of the water being added at the
nozzle) are dealt with in ISO 20182.
This International Standard does not apply to the gunning of plastic refractory materials (refer to
ISO 1927-1).