The Series 4400 Chemical Injectors are electric motor driven, positive displacement pumps utilizing an integral worm gear drive available in three different standard ratios and plunger sizes to provide a wide selection of volumes and pressures from 0.5 GPB up to 160 GPB per head, against pressures up to 2400 psig. Pumps are standard with a micrometer type stroke adjustment that puts an end to the tedious work of stopping and starting the pump while trying to set the proper flow rate. A 0-100% change in capacity is possible while the pump is running. Each complete turn of the knob results in a 10% change in stroke setting.Repeatable accuracy is +/- 1% of set point. Up to two heads driven by a common motor are possible, and each head can be independently adjusted.The standard, virtually trouble free packed plunger injector heads have built-in priming valves in a drip-ring barrier that will prevent chemicals from being conducted along the plunger and into the gear box. Standard pumps can be furnished with high strength ductile iron or all stainless steel liquid ends to handle a wide variety of chemicals used in oil and gas production facilities, pipelines, process plants and other applications where a rugged, easy to maintain proportioning pump is required.