Thread type: W Cylindrical - gas cylinder valve thread DIN 477

The table W cylindrical for gas cylinder valve threads includes all cylindrical threads that are approved for use on gas cylinders in accordance with DIN 477. In addition to the W cylindrical thread, there are also tapered threads for gas cylinder valves. As the use of gases is always associated with a certain risk of accidents, special safety measures are required when handling gas cylinders and their components. These safety measures include the strict regulation of gas cylinder valve threads such as the W cylindrical thread in the table below.

The idea behind the extensive W cylindrical table for gas valve threads is to make it impossible for the user to connect gas cylinders incorrectly. The large number of entries in the W cylindrical thread table minimizes the probability of creating explosive connections due to ignorance or carelessness. The W cylindrical thread table therefore contributes to the safe handling of gases of all kinds. It is important to note that you must not interfere with these safety measures of the W cylindrical thread table by using bypasses or adapters. If a connection cannot be made according to the W cylindrical thread table, this is a safety mechanism that should not be overridden by force.

The W cylindrical thread table looks different from conventional thread tables. Instead of a list of different sizes of the same thread type, the focus here is on the connection type. On the far left of the table for the W cylindrical thread, you will see a numbering system. Each number is assigned to a connection that can be clearly identified in this way in accordance with DIN 477. This is followed in the next column of the W cylindrical thread table by the approved gas types that can be combined with the connection. Some connections in the W cylindrical thread table are approved for a variety of gas types, others for only one. Only in the last column of the W cylindrical thread table can you find information on the gas cylinder valve thread that is assigned to a connection and therefore also to one or more gas types. In addition to the W cylindrical thread type, the table also lists tapered gas valve threads, G pipe threads or metric M threads. Further information on the thread type in the W cylindrical thread table indicates whether it is a left-hand or right-hand thread. Left-hand threads are used in the W cylindrical thread table for gases such as propane, which are frequently used in the household. The left-hand thread provides special protection for private individuals who are not experienced in handling gas cylinders.

Connection 
No.
Approved Gas TypesThread
1Arsine, 1,3-butadiene, butane, 1-butene, chloroethene, chloromethane, deuterium, difluoromethane (R32), dimethyl ether, 2,2-dimethylpropane, ethane, ethene, ethylene, isobutane, isobutylene, methane, hydrogen phosphide (Phoshin) propane, propene, silicon hydride (silane), hydrogenW 21,80 x 1/14"
left
2Butane, isobutane, propane (up to 33 liter volume)W 21,80 x 1/14"
left
3AcetyleneClamping bracket
5Dichlorosilane, carbon monoxide, hydrogen sulfideW 1"
left
6Ammonia, argon, chlorodifluoromethane (R22) helium, carbon dioxide, krypton, neon, octafluorocyclobutane (R C318), octafluoropropane (R 218), sulfur hexafluoride, carbon tetrafluoride (R14) Tifluormethan (R23) XenonW 21,80 x 1/14"
right
7Ssulfur dioxideG 5/8"
8Boron trichloride, boron trifluoride, hydrogen bromide, chlorine, hydrogen chloride, hydrogen fluoride, nitrogen dioxide, nitric oxide, nitrogen trifluorideW 1"
right
9Oxygen calibration gas (oxygen) 21%)G 3/4"
right
10NitrogenW 24,32 x 1/14
right
11Nitrous oxide (normal connection)G 3/8"
right
12Nitrous oxide (up to 3 liters of volume)G 3/4"
right, internal
14Test gas (oxygen <21%)M 19 x 1,5
left
52Non-flammable and non-toxic gases filling pressure 300 barM 30 x 1,5
right, internal
54non-flammable, non-toxic and non-oxidizing gases and gas mixturesW 30 x 2 (15,9 / 20,1)
right
55Non-flammable, toxic and corrosive gases and gas mixturesW 30 x 2 (15,2 / 20,8)
right
56Compressed airW 30 x 2 (16,6 / 19,4)
right
57Flammable, non-toxic gases and gas mixturesW 30 x 2 (15,2 / 20,8)
left
58Flammable, toxic and corrosive or non-corrosive gases and gas mixturesW 30 x 2 (15,9 / 20,1)
left
59Oxygen and oxidizing, non-toxic, non-corrosive gases and gas mixturesW 30 x 2 (17,3 / 18,7)
right
60Oxidizing, toxic and / or corrosive gases and gas mixturesW 30 x 2 (18 / 18)
right
0170Argon, helium, nitrogen, charge pressure> 200 to 300 barW 30 x 2
right
Gas cylinder valve protection capW 80 x 1/11"
right
Cross section of cylindrical gas cylinder valve thread