Norriseal-WellMark is an ISO 9001-certified manufacturer of engineered valve and control solutions, including control valves, ... angle-disc butterfly valves, safety relief valves, check valves, positioners, actuators, level controllers, transmitters, switches, pressure controllers and pressure regulators. Renowned for innovative design and dependable quality, our products are used worldwide in oil and gas applications, as well marine, power generation, HVAC and other industries. We are a solutions provider, backing our products with responsive customer service, in-depth applications assistance, and in-house engineering and technical support. To learn more, visit www.norrisealwellmark.com. read more