The start to discharge pressure shall, however, in no case be such that liquid would escape from the valve(s) if the portable tank were overturned.

6.6.3.5.3 For filling and discharge openings the first shut off device shall be an internal stop valve and the second shall be a stop valve placed in an accessible position on each discharge and filling pipe.

Pressure relief requirements are as indicated in 6.6.2.8.3 to prevent crystallization of the product in the pressure relief valve.

After discharge the device shall close at a pressure not more than 10 below the pressure at which the discharge starts.

6.6.2.8.5 When the shell is fitted for pressure discharge, the inlet line shall be provided with a suitable pressure relief device set to operate at a pressure not higher than the MAWP of the shell, and a stop valve shall be fitted as close to the shell as reasonably practicable.

These devices shall, after discharge, close at a pressure not lower than 10 below the pressure at which discharge starts and shall remain closed at all lower pressures.

These devices shall, after discharge, close at a pressure not lower than 10 below the pressure at which discharge starts and shall remain closed at all lower pressures.

(a) Each plug or valve shall have a taper threaded connection directly to the pressure receptacle and be capable of withstanding the test pressure of the pressure receptacle without damage or leakage

(b) the allowable tolerance at the discharge pressure for spring loaded devices

Its unique cool flow valve can efficiently discharge hot and damp exhaled breath from inside the respirator, allowing easier breathing for users.

The frangible disc shall rupture at a nominal pressure 10 above the start to discharge pressure of the relief device.

The frangible discs shall rupture at a nominal pressure 10 above the start to discharge pressure of the relief device.

(a) the pressure (in bar or kPa) at which it is set to discharge

Fuel cell cartridge means a container that stores fuel for discharge into fuel cell powered equipment through a valve(s) that controls the discharge of fuel into such equipment and is free of electric charge generating components.

(a) the maximum effective gauge pressure allowed in the shell during filling or discharge or

Each pressure receptacle with a wall thickness at any point of less than 2.0 mm and each pressure receptacle that does not have fitted valve protection shall be transported in an outer packaging.

Civil Horizontal Valve

(releases air valve)

(a) the pressure (in bar or kPa) or temperature (in C) at which it is set to discharge

(b) Each valve shall be of the packless type with non perforated diaphragm, except that, for corrosive materials, a valve may be of the packed type with an assembly made gas tight by means of a seal cap with gasket joint attached to the valve body or the pressure receptacle to prevent loss of material through or past the packing

Cylinder head valve grinder

Cylinder head valve grinder

Maximum allowable working pressure (MAWP) means the maximum effective gauge pressure permissible at the top of the shell of a loaded portable tank in its operating position including the highest effective pressure during filling and discharge

6.6.2.9.2 The required pressure relief device shall be set to start to discharge at a nominal pressure of five sixths of the test pressure for shells having a test pressure of not more than 4.5 bar and 110 of two thirds of the test pressure for shells having a test pressure of more than 4.5 bar.

The external discharge fittings (pipe sockets, shut off devices), the stop valve and its seating shall be protected against the danger of being wrenched off by external forces (for example using shear sections).

Vehicle jack Cylinder head valve grinder

The external discharge fittings (pipe sockets, shut off devices), the internal stop valve and its seating shall be protected against the danger of being wrenched off by external forces (for example using shear sections).

6.6.2.12.2 The combined delivery capacity of the relief devices in condition of complete fire engulfment of the portable tank shall be sufficient to limit the pressure in the shell to 20 above the start to discharge pressure of the pressure limiting device.

When the shell is to be subjected to a significant vacuum before filling or during discharge it shall be designed to withstand an external pressure of at least 0.9 bar gauge above the internal pressure and shall be proven at that pressure.

6.6.4.5.9 When pressure building units are used, the liquid and vapour connections to that unit shall be provided with a valve as close to the jacket as reasonably practicable to prevent the loss of contents in case of damage to the pressure building unit.

This is called a cycle valve tube.

6.6.2.6.4 For a lined shell, the internal stop valve required by 6.6.2.6.3.1 may be replaced by an additional external stop valve.

They need not be protected against inadvertent discharge provided that measures to prevent dangerous build up of pressure and dangerous atmospheres are addressed.

The capacity and start to discharge pressure of the relief valves shall be based on the results of the tests specified in 4.2.1.13.1.

6.6.2.14.1 Connections to pressure relief devices shall be of sufficient size to enable the required discharge to pass unrestricted to the safety device.

6.6.3.10.1 Connections to pressure relief devices shall be of sufficient size to enable the required discharge to pass unrestricted to the safety device.

6.6.4.9.1 Connections to pressure relief devices shall be of sufficient size to enable the required discharge to pass unrestricted to the safety device.

6.6.3.5.2 All openings with a diameter of more than 1.5 mm in shells of portable tanks, except openings for pressure relief devices, inspection openings and closed bleed holes, shall be fitted with at least three mutually independent shut off devices in series, the first being an internal stop valve, excess flow valve or equivalent device, the second being an external stop valve and the third being a blank flange or equivalent device.

6.6.3.5.5 In addition to filling, discharge and gas pressure equalizing orifices, shells may have openings in which gauges, thermometers and manometers can be fitted.

And this is how you make a valve.

6.6.4.5.2 Each filling and discharge opening in portable tanks used for the transport of flammable refrigerated liquefied gases shall be fitted with at least three mutually independent shut off devices in series, the first being a stop valve situated as close as reasonably practicable to the jacket, the second being a stop valve and the third being a blank flange or equivalent device.

6.6.2.5.6 Each stop valve or other means of closure shall be designed and constructed to a rated pressure not less than the MAWP of the shell taking into account the temperatures expected during transport.

6.6.3.5.9 Each stop valve or other means of closure shall be designed and constructed to a rated pressure not less than the MAWP of the shell taking into account the temperatures expected during transport.

6.6.4.5.8 Each stop valve or other means of closure shall be designed and constructed to a rated pressure not less than the MAWP of the shell taking into account the temperature expected during transport.

(v) the valve shall continue to be effective in the event of damage to the external device for controlling the operation of the valve