Introduction

In the chemical industry, process pressures are climbing higher and higher. The utility field, with its high steam pressures and hydraulic and pneumatic shutdown systems, demands the utmost in reliability. Nuclear power plants with their “hot” materials also have massive reliability problems. Such problem areas have given rise to the increased use of the permanentweld- type tube fittings which provide a sturdy, tight integral line system that remains unaffected by shock, vibration or thermal distortion. The Parker Weld-lok® line of permanent socket weld tube fittings meets the most exacting requirements of any system.