The LPI system is ideal for small projects and unique conditions that prohibit the use of significant pressure. For example, low pressure techniques are often used for delicate architectural surfaces because they allow the use of low strength capping adhesives such as sealants that can be removed without marring the surface of the concrete. The pressure regulator is specially manufactured so that the dispense pressure cannot exceed 15 psi. (1 bar). Since the LPI uses very low pressure, penetration requires more time than with higher pressures. For this reason, super thin resins with a long working life work great.
The results available with high pressures are usually available at low pressures as well: it simply takes longer. Low pressure injection is popular largely because of the low initial equipment cost and ease of installation. The procedure is straightforward, requiring little equipment and know-how. Resin is pre-mixed in a disposable plastic bowl which is then pressurized to flood a circuit of plastic tubing connected to a series of porting adapters. All of the ports are injected simultaneously. Pressure is maintained until the resin has gelled within the tubing.
The dispenser consists of a steel frame with a collar to support the disposable bowl, a lid, a clamping device to secure the lid, and brackets to mount a regulator and pressure gauge.