The foam pump is supplied by the Foam Pump Suppliers(KEXON).Foam concentrate pumps, their controls, and general piping arrangements now follow the requirements of Nfpa 20 and I have related questions:
1. In main/reserve, dual pump, installations, is an individual control valve required for each pump on the discharge side of the pump check valve even if there is a shutoff valve on the common discharge to the ratio controller?
2. Sensing lines occur in both fire water pump systems and foam pump systems. Water pump systems utilize sensing lines for requirements of pressure drop starting. Foam pumps, with listed and Nfpa recognized controls, can be started much the same way. Sensing lines are also necessary for a balanced pressure pump system for sensing the incoming water pressure to the ratio controller and sensing that water pressure signal to the balancing valve where it adjusts the foam liquid pressure from a like sensing line on the foam pump discharge. Nfpa 20 dictates sensing lines to be of metallic construction and no less than 1/2" size. Should this requirement be applicable to balance pressure sensing lines on foam pump applications? Should a manufacturer be allowed to use what they consider "equivalency" under Nfpa #11, section 1.5, if it doesn't meet all the criteria established in that paragraph?
Ningbo KeXon Plastic Co., Ltd. is a comprehensive plastic packaging enterprise integrating design, production, and sales. We own a factory (Yuyao KeXon Sprayer Factory), and its plant area is over 6,000 square meters, with more than 20 years of production experience in various types of daily packaging. The company can professionally produce all kinds of foam pumps, plastic caps, daily and medicinal plastic bottles, as well as all kinds of trigger sprayers, lotion pumps, perfume sprayers, cream jar and other products.