OPW Engineered Systems Loading Valves are designed to shut off the flow without causing damaging shock in the pipeline. Pipeline shock, or "hammer," causes problems with pipe joints and instruments in the line. Fast, shockless closing is assured by use of an adjustable needle valve, and a dashpot. Air cannot be trapped in the valve so the valve does not open after closure. This variable closure rate controls shock with minimum afterflow. Loading valves are available in several styles to fill almost any liquid transfer requirement where versatility and ease of operation are desired.

The 6400 series horizontal loading valve, made in cast aluminum, is "soft closing" in order to reduce line shock. The valve connections are tank-truck (TTMA) flanges. The sturdy valve has a "deadman" feature that requires the operator to hold the handle in the open position while loading. The trim inside the body is stainless steel, which means this valve can be used for a variety of chemicals and fuels. Available seals are Buna-N, Ethylene Propylene or Fluorocarbon for versatility in handling a wide range of fluids within the parameters of the body and trim limits. Available in 3" and 4" sizes.