This section evaluates antechambers in comparative terms between rectangular design and cylindrical design.

Why, because cylindrical antechambers are less expensive to make than rectangular antechambers, and for some applications this is good enough reason.

But, rectangular antechambers are functionally superior, consume less gas, require less pumping down and take less operational time, and for us that means PRODUCTIVITY ENHANCEMENT™.

For an antechamber to be functional to requirements, a designer must assess its practical usage and come to a conclusion on the most appropriate size. Our researched assessment shows that a Winchester bottle or electronic balance is the largest single item to be regularly transferred into and out of the glove box and hence we make that the control size in cross section of 23cm wide x 33cm high or 759cm² of used area. Other items are usually slim but within the 24" or 61cm which dictate the length of the standard commercial antechamber.

The cylindrical antechamber is usually 15" or 38cm in diameter and equates to a cross sectional area of 1194cm². Deducting our control size area of 759cm², the unused area is 435cm². This unused area equates to a volume of 26,100cm³ over the 60cm length of the cylindrical antechamber or 26.1 litres. The rise and fall doors of a cylindrical antechamber (which do not contribute to usable space due to their guillotine action) account for an additional 3 litres due to their domed shape, to give a total of 29.1 litres of unused volume. This unused volume is a direct result of the design, in that on all sides of the rectangular usable space, there is a large wasted volume created either by the cylindrical tube or the dished end doors.

PRODUCTIVITY ENHANCEMENT™. ONE

Our design of antechamber is 25cm wide x 35cm high with a cross sectional area of 875cm² with a difference, representing unused area, of only 116cm² between the control area of 759cm². This unused area equates to a volume of 6960cm³ over the 60cm length of the cylindrical antechamber or 6.96 litres As our end doors are flat no additional unused volume is accountable to give a total of 6.96 litres of unused volume

Now that difference of 22 litres has to be evacuated and backfilled with gas at least three times per antechamber conditioning routine, which equates to 66 litres of additional evacuation and 66 litres of additional gas every time the antechamber is used. That can work out to 137,000 litres over a year with just one operational use of the antechamber per hour.

PRODUCTIVITY ENHANCEMENT™.TWO

The antechamber conditioning routine alternates between evacuation and gas backfill to flush out the air content and replace the volume with a gas to near quality of the glove box. This routine can be carried out manually or automatically with varying degrees of operator time involvement by:

(a) Direct manual manipulation of a vacuum valve and gas valve whilst observing a compound pressure gauge.
(b) Manual initiation of push buttons operating solenoid valves whilst observing a compound pressure gauge.
(c) Manual initiation of an automated process that is switched over by fixed pressure switches.
(d) Manual initiation of an automated process that is switched over by user set pressure switches.

The implications on operator time become evident when assessed against the minimal equipment requirements (a) to achieve antechamber conditioning, and the equipment specification (d) to achieve the most productivity enhancement. Releasing the operator from the manual and observational tasks can alone amount to 10 minutes in total for each time the antechamber is used. The ongoing savings in time and consumable gas using our high specification rectangular antechamber is a proven fact

PRODUCTIVITY ENHANCEMENT™.THREE

Our antechamber, because of its rectangular design, allows for the outside door to be either end loading or front-loading. A front-loading antechamber maximises laboratory space and is ergonomically superior to that of an end-loading antechamber. However, user preference prevails in the choice of design, which is usually determined by the glove box duty requirements.

Either design has our horizontally sliding doors that glide on Teflon bearings, and their limited travel over only 25cm means no stretching to reach as required with cylindrical antechamber doors. Additionally our antechamber doors have no gas springs or counterbalance weights to overcome.

PRODUCTIVITY ENHANCEMENT™. ONE + TWO + THREE

Truly a design for those that place a value on antechamber performance, energy conservation and fatigue limitation and these are standard supply on our R& D, Academic, and Optimum glove box systems.

Optionally (because its not wanted by all) we can supply a telescopic tray inside the antechamber. This tray will, on the end-loading antechamber, extend beyond the door line by 75% either direction, or a similar extension on the inner door of the front loading design.

Our door interlock system will ensure you never put to risk operators or process material by inadvertently overlooking the antechamber conditioning or door closing routines. Specified where there is, or potentially is, a toxic presence within the glove box, or where there is a need to qualify the antechamber conditioning status prior to opening the inner door, or ensure only one door is open at any point of time.

The double door interlock system integrates door limit switches and lever latch solenoid bolt locks, to the glove box system control and display, allowing for an integrated approach to operator protection, product protection, quality control, process control and operational data acquisition.

Our antechambers are available in standard format as follows;

Variations to this design are available from stock design including "T" antechambers and where not, can be custom designed.

Other designs of antechamber are available including cylindrical end opening, "T" configuration, and custom designed.

Our designs for antechambers include for applications across our full range of glove boxes in stainless steel and polymers.

An antechamber is the most used single item of facility on a glove box, and its functionality is pivotal to the process operation of a glove box. It deserves detailed attention in a glove box design specification, and requirements should be assessed with the total process operation and operator interface in mind.

Our engineers will be pleased to review design options and possibilities for any application to ensure your ultimate choice is the optimum one for your application and budget.

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