English to Spanish Tech/Engineering Petroleum Eng/Sci Tuberias de gas

For new systems, strategic valves will normally be installed either side of special crossings (including major river crossings), at offtakes for pressure reduction installations, and at other locations where required for network isolation purposes (based on risk assessment). Newly installed valves will have provision for a pressure/rider point on each side.
Realizo esta pregunta en Proz porque lo que dice el Simon and Schusters no me parece adecuado: jinete, anexo, vuelta de cabo. He consultado los glosarios de Proz y he hecho busquedas en la web, pero solo ha aumentado mi confusion.