Rule 901:5-3-06 | Container appurtenances.
(A) All appurtenances shall be designed for not less than the maximum working pressure of that portion of the system on which they are installed. All appurtenances shall be fabricated from materials proved suitable for anhydrous ammonia service;
(B) All connections to containers except safety relief devices, gaging devices, or those fitted with a no. 54 drill size orifice shall have shut-off valves located as close to the container as practicable;
(C) Excess flow valves where required by these rules shall close automatically at the rated flows of vapor or liquid as specified by the manufacturer. The connections and line including valves and fittings being protected by an excess flow valve shall have a greater capacity than the rated flow of the excess flow valve;
(D) Liquid level gaging devices that require bleeding of the product to the atmosphere and which are so constructed that outward flow will not exceed that passed by a no. 54 drill size opening need not be equipped with excess flow valves;
(E) Openings from container or through fittings attached directly on container to which pressure gage connections are made need not be equipped with excess flow valves if such openings are not larger than no. 54 drill size;
(F) Excess flow and back pressure check valves where required by these rules shall be located inside of the container or at a point outside as close as practicable to where the line enters the container. In the latter case, installation shall be made in such manner that any undue stress beyond the excess flow or back pressure check valve will not cause breakage between the container and the valve;
(G) Excess flow valves shall be designed with a by-pass not to exceed a no. 60 drill size opening to allow equalization of pressures;
(H) Shut-off valves provided with an excess flow valve shall be designed for proper installation in a container connection so that the excess flow valve will close should the shut-off valve break;
(I) All excess flow valves shall be plainly and permanently marked with the name or trade-mark of the manufacturer, the catalog number, and the rated capacity.
Supplemental Information
Amplifies: –
Five Year Review Date: