Abstract: A chemical injection valve, for use with either an outside mount or side pocket mount gas lift mandrel for injecting chemicals, hot oil and the like into production tubing. The valve has a tubular housing with fluid inlet ports and fluid outlet means with a longitudinal bore connecting the inlet ports and the fluid outlet means. A biased valve metering member is positioned in the bore between the fluid entry port and the fluid outlet means to regulate the flow of fluids therebetween. A fluid by-pass is provided in the housing which is opened and closed by the biased valve metering member in response to the greater to the pressure of fluid entering the fluid entry port or biasing means acting on said valve metering member. When opened, the by-pass provides fluid communication between the fluid entry ports and the fluid outlet means. The biasing means is a spring having a predetermined spring force. Means are provided for adjusting the spring force.

Abstract: Double acting, gas operated pumps for lifting formation fluids from a well are disclosed as comprising a housing connectible to the lower end of a production string suspended within a well, and a pump assembly which may be lowered into and raised from a landed position within the housing. Upper and lower pump chambers are formed in the pump assembly and a piston is reciprocable in each chamber in response to the alternate supply and exhaust of a pressurized gas to one side thereto for alternately admitting formation fluid to the other side of one piston while pumping it from the other. The spool of a reversing valve for controlling the flow of gas to and from the chambers is connected to one of the pistons in such a manner that it is shifted into its alternate positions with a snap action.