When mixing perlite and vermiculite concrete, air entrainment and progressive cavity pumps should be used. It is important to remember that there are different forms of air entraining agent and different concentrations. By listing these products, we do not not necessarily endorse them or assume any liablity for them or for any mixes made with them. Generally, progressive cavity pumps and not piston pumps should be used with perlite and vermiculite concretes.
Piston pumps tend to crush and break the lightweight aggregates causing a reduction in yield.
Pumping Hoses Rubber concrete pumping hoses should be a minimum of 3 inches. Smaller diameter hoses increase hose pressure and will result in a greater loss of yield and increased pump, rotor and stator wear. Use only as much hose as is necessary and where the hose goes over a wall make certain that it does not kink. On high rise construction, tie the hose off at each joint.