GB2553185A

GB2553185A - Valve guard with anti-rotation provision

Info

Publication number: GB2553185A
Application number: GB1708364.3A
Authority: GB
Inventors: Van Nieuwenhuijzen Dies
Original assignee: Linde GmbH
Current assignee: Linde GmbH
Priority date: 2016-05-25
Filing date: 2017-05-25
Publication date: 2018-02-28
Also published as: GB201708364D0

Abstract

A valve guard 10 has two halves 15a, 15b that can be bolted together to an adapter ring 20. Each guard half includes on the inside an extended portion that when bolted together meet the wrench flats 55a, 55b of the valve. The engagement of the extended portions with the valve wrench flats prevents the guard from rotating.

Description

(54) Title of the Invention: Valve guard with anti-rotation provision Abstract Title: Valve guard (57) A valve guard 10 has two halves 15a, 15b that can be bolted together to an adapter ring 20. Each guard half includes on the inside an extended portion that when bolted together meet the wrench flats 55a, 55b of the valve. The engagement of the extended portions with the valve wrench flats prevents the guard from rotating.

FIG. 1

At least one drawing originally filed was informal and the print reproduced here is taken from a later filed formal copy.

1/1

08 17

VALVE GUARD WITH ANTI-ROTATION PROVISION

FIELD OF THE INVENTION (θθΐ) The invention relates to a valve guard for a gas cylinder valve.

BACKGROUND OF THE INVENTION (002) Cylinder valve assemblies for gas cylinders and the like are known in the art. Cylinder valves and valve stems may be damaged by inadvertent contact with other structures or objects, such as walls or other cylinders. This is particularly an issue when it is required that the cylinder be moved. During such movement or transport, the cylinder may be dropped or knocked over, which can cause considerable damage to the valve or valve stem.

(003) Damage to the cylinder valve or valve stem may compromise the retention and release of gas contained in the cylinder and may also compromise the structural integrity of the valve or cylinder. This may result in dangerous conditions where the cylinder valve does not meet specifications or regulations, and therefore cause the cylinder to be unavailable for use.

(004) In order to avoid damage to cylinder valves and valve stems, it is common to employ a valve guard which attaches to the cylinder and provides protection of the valve assembly.

(005) The International Organization for Standardization (ISO) sets standards for gas cylinders among other things. This includes standards related to interaction between valve guards and gas cylinders. ISO 11117 specifically provides standards for the design, construction and testing of valve protection caps and valve guards. According to ISO 11117, the minimum torque at which a guard (plastic) can be rotated relative to the cylinder is 30 Nm. However, especially during movement of the cylinder, when the guard may be used for carrying or handling the cylinder, this minimum torque may be exceeded. This can result in the guard rotating and potentially blocking access to the valve, e.g. hindering access to the shut off valve and regulator hand wheel, rendering the valve inoperable.

(006) There is a need in the art for improvement to valve guards for gas cylinders.

SUMMARY OF THE PRESENT INVENTION (007) The invention provides an improved valve guard for gas cylinders.

(008) BRIEF DESCRIPTION OF THE DRAWINGS (009) Figure 1 is a plan view of a valve guard according to the invention.

(010) Figures 2a and 2b are views of a cylinder valve and valve stem showing where the valve guard of the invention contacts the valve and valve stem.

DETAILED DESCRIPTION OF THE INVENTION (OH) Valve guards allow access to the valve hand wheels and outlet/filling ports, such as those for VIPR (Valve with Integrated Pressure Regulator) type valves. As noted above, the minimum torque set by the ISO provision may be exceeded during handling or transport of the gas cylinder. This may result in the guard rotating to a position that then blocks the access to the valve hand wheels, filling port and outlet thus rendering the valve and cylinder inoperable.

(012) In fact the ISO provision on minimum torque is particularly applicable to a VIPR type valve for the following reasons:

an adapter ring is used for fitting the guard to the cylinder; there is no positive locking, but rather friction with the adapter ring prevents rotation;

the plastic guard material may show relaxation over time resulting in loosing with the adapter ring;

there is a tight fit to the VIPR outlet, filling port and valve wheels such that a small rotation of the guard will hinder access.

(013) The invention overcomes these problems by providing a new design for the valve guard that prevents rotation of the valve guard at torque exceeding the minimum of the ISO provision.

(014) In particular, the VIPR is fitted to the cylinder with a torque of 190-210 Nm (per ISO 13341) which is considerably higher than the minimum torque at which of the guard shall not rotate (30 Nm). Therefore, the VIPR can be used to more stably fix the guard in place.

(015) The design of the guard according to the invention comprises two plastic parts that can be bolted together to an adapter ring. A dedicated groove in the adapter ring matches with a rib on the internal guard base to provide secure engagement, with the adapter ring that is threaded to the cylinder neck ring.

(θ16) Each guard half includes on the inside an extended portion that when bolted together meet (with a small tolerance) the wrench flats of the valve. In this manner, if the rotational torque exerted on the guard exceeds 30 Nm, the extended portions grip the valve wrench flats and prevent the guard from rotating.

(017) The invention will be further explained with reference to the drawing figures. Figure 1 shows the valve guard 10, of the invention which comprises two plastic parts 15a, 15b, that can be bolted together to an adapter ring 20. The extended portions shown by the arrows 25a, 25b, will engage the wrench flats shown by arrows 55a, 55b (see Figures 2a and 2b) of the valve 50, upon fully tightening the guard halves together. If rotational torque is applied in excess of the 30 Nm set by ISO 11117, then the engagement of the extended portions with the wrench flats of the valve 50, prevent the rotation of the valve guard 10.

(018) The advantages of the guard of the invention are that by preventing rotation of the guard, there is greater certainty that the access to the VIPR operating mechanisms, e.g. valve hand wheels, filling port and outlet, will be maintained.

(019) It is anticipated that other embodiments and variations of the invention will become readily apparent to the skilled artisan in the light of the foregoing description, and it is intended that such embodiments and variations likewise be included within the scope of the invention as set out in the appended claims.

Claims

What is claimed:

1. A valve guard as described herein.