B. A. TARGETT

Above-ground garages

Basically, there are two types of above-ground g11:rages; those needing to be licensed and clearly to the provisions of the Petroleum Spmt (Motor ':'eh1cles) Regulations, 1929. The Regulations are specific and discussion of them is unnecessary.

For licensed above-ground garages the following standards of separation between them and the remainder of a building is to be recommended: (a) garages under 5,000 cu. ft.--! hour (b) garages from 5,000 cu. ft. to 75,000 cu. ft.-1 hour (c) garages from 75,000 cu. ft. to 250,000 cu. ft.-2 hours (d) over 250,000 cu. ft.-4 hours

The fire cell size of any garage should be restricted to a maximum of 500,000 cu. ft. in extent or 40,000 sq. ft. in floor area. Fire cells should be separated one from the other by fire division walls each of a four hour standard of fire resistance. Openings in a fire division wall may be allowed provided that they are fitted with double sets of fusible link shutters.

Means of escape should be so arranged that no part of a garage floor is more than 100 feet from an escape door. Escape routes should be enclosed by fire-resisting partitions and should discharge wherever possible directly to the open air. Any doorway openings in partitions for!11ing part of the separation between a garage and the of the buildings should be fire-resisting and se_lf-closmg. Any surface drainage in the garage should pass via trapped gullies to a petroleum interceptor. It is also essential to ensure good cross-ventilation to garages.

FUTURE TRENDS IN PETROLEUM SPIRIT DISPENSING

B. A. Targett, Assistant Chief Engineer Wayne Tank and Pump Co., Ltd.

Introduction

Probably five years ago, and certainly ten years ago, this lecture would not have contained more than fifteen minutes of subject matter of any interest, insofar as trends in petroleum dispensing equipment were concerned. However, in the last five years, there has been a considerable acceleration in the rate of progress, particularly in the technical aspects of equipment design, as a result of which it will be impossible for me to cover the full extent of past achievement, and beyond my imagination to exhaust the possitilities of future trends, in the time available. 1 propose dealing with as wide a field as possible under four main headings in the chronological order of their development. The first of these is remote pumping.

Remote Pumping Systems

The original concept of remote pumping syste!11s resulted from an investigation of ways to handle changmg system requirements, prompted by the following factors. 1. The increasing number of dispensing outlets per station. 2. Longer pipe runs from tank to dispensers. 3. Greater product storage capacity. 4. Increasing product volatility. 5. Difficult geographical locations where high temperature or low atmospheric pressure affected conventional equipment performance.

These factors are typified by a large motorway service area dispensing high grade fuels at high altitude in a tropical climate and, under such conditions, a suction lift pump, if it worked at all, would be grossly inefficient. Even under conditions more typical of the United Kingdom, some of the factors enumerated are relevant and sometimes inhibit the use of conventional equipment.

Before describing future trends in remote pumping, a brief review of past development may be instructive, if not entertaining, as the first example shows. This was a very early system known as the "Aqua System", which used the mains water supply to pressurise the entire underground system, including the tank. When the dispenser nozzle was opened, water displaced petrol in the storage tank under mains pressure through the system. The obvious disadvantage of this method is the necessity for providing a substantial pressure vessel for storage.

Another approach to remote pumping was, and is, t0 utilise gravity to transfer the product from an above ground storage tank to the dispensing outlet. Limiting head and varying flow rate are objections to this system. With the advent of power operated lift pumps, some of the inherent disadvantages of suction systems could be eliminated by removing the pump from the dispenser and placing it near the storage tank. Such units were compact and included all the hydraulic components except the meter. Utilising the integrated motor, pump and air separation system of the Wayne Solo Unit, it became possible to install remote suction pumps within the confines of the storage tank pit itself. . However, future trends in remote pumping are most likely to revolve around submersible pumps which, as the name implies, are designed to be submerged in the storage tank. A submerged pump operates under what is known as a flooded suction, the positive suction head being the height of the liquid level in the storage tank above the pui:np inlet. In consequence, such a pump is always primed whilst the fuel level is above the inlet and its performance is sensibly independent of atmospheric pressure. Furthersince the delivery line between the storage tank and dispenser is under pressure during pump operation, the formation of vapour locks and other phenomena associated with suction pumps are avoided.

The pump is installed in the supply tank by means of an eight inch riser pipe and manifold from which the pump and motor unit may be extracted and re-inserted if necessary. The manifold has provision for two two-inch discharge pipes to remote dispensers and incorporates an integral check and pressure relief valve, together with an installation wiring compartment and an air release assembly which bleeds air back to the tank. The extractable unit consists of the discharge head from which the pump and motor unit is suspended by means of the discharge pipe. A separate electrical conduit runs from the motor control gear to a sealed junction box in the discharge head.

MODEL E;-8F SUBMERSIBLE PUMP

The motor is interestincr in havincr stator and rotor windings totally encapsulated in epo~y resin and being cooled by fuel trapped within the casino and circulatincr around the outside. A combined cun~nt and thermal overload is contained in a separate sealed compartment above the m?tor. The pump is a single stage directcoupled centrifugal type which will not pump air.

Pu1!1p performance varies with installation factors which contnbute to pressure loss in the system, and ratings must ther~fore be based on representative conditions. The ~i:aximum nui;nber of dispensers ~mgl~ pump 1s only limited by that may be served the acceptable flow by a rate perb dispen~er , and conventional ideas about this may have ~I . ~ ~odified

wi~h the advent of self-service equipment, iic 1 · shall be discussing later on.

That is all we have time for on descriptive matter. However, I would like to say that this equipment is ~pro_ved by Underwriters Laboratories focorporated of H menca and has not met any serious objection by the h ome Office, Board of Trade or any other authority we 4gve consulted. It is presently specified and used in over

per cent of all new installations in the U.S.A.

Blending

G Some time ago I addressed the West Midlands Petroleum r~up on t~e subject of petrol blendina equipment This equipment d · .

0 · low octa is .esigned to mix two base fuels of high and of inte n~~ating ~espectively to produce a range of fuels of ble r~e

t iaJ~ rating. n dmg ispenser At that time .I known as the discussed one type proportional price j;~~aan "a

lthou~h blending pumps are of no special sigtion ~c~ 1

111 ;elation to the interpretation and administrat rend o . ie etroleum Acts, I am going to briefly review . s ~me~ tl~en, as this type of equipment is undoubtedly increas1~g 111 importance. t A vana.ble ratio blending pump is essentially two separa e tl?urnp1 mg and metering systems, very similar to a conven 10na two prod d' h f th t . uct 1spenser, except t at the output 0 e wo meters _ is monitored by a proportioning valve o

pe~ated hby a special computer. The valve is of the sliding car on s oe type, the shoes being radially mounted on a common shaft. The cylindrical valve chamber is divided for e~c~ product, and the outlet ports, whose openings are d~tei mined by the positions of the carbon shoes, are axially dispose~ a.nd communicate with each chamber. After P.roportionmg.' the products are passed through individual s igh~ gla s:!s mto concentric hoses . to the nozzle, where m1x111g takes place.

1:"he most novel part of a blending pump is the computer, which not only performs the normal functions of indicating the quantity dispensed and but also controls the accuracy computing its cash value, of the blend throu<>h the proportioning valve. The proportional price type of computer was fully described in the your Association for January, 1963, Quarterly Journal of in reporting the text of 1'.1Y original lectu'.e. I shall, therefore, only make passmg reference to this type.

Each meter drives a conventional computer variator unit, the respective outputs of which are summated to give a total sale price. mation also, but The total quantity is obtained without the intervention of by sumvariator gearing. Blend valve control is achieved by balancing the speeds of the two meters in a subtracting differential gear, the output of which is attached to the proportioning valve.

Large scale marketing experiments with proportional pricing blending pumps have shown certain difficulties in meeting pricing structures required by oil companies. As a result, it is probable that the proportional system will be replaced by an alternative, known as increment pricincr. A few increment blending pumps have been in use fir some time, but the current production model is styled to match the Wayne 1700 Series. The range of products available is displayed on the dial, together with the unit price of each. The required grade is selected by means of a knob and release lever on the side of the pump, movement of which cannot take place whilst the pump is dispensing. Internally, the tional price type, components are identical except for the computer. to the This is proporof quite different aspect to the proportional computer, with a conventional counter section surmounting a special variator unit and price increment gearbox. In front of the variator are the unit price wheels and a grade indicator drum.

The essential feature of this design is that the basic unit price is that of the low grade fuel, the combined volume being priced at this figure by the special variator. A unit price increment, arbitrarily preset in the increment gearbox by the station operator, is selected for each blend by the blend selector, and a total price increment, proportional to the total quantity, is added to the base price computed by the variator. The steps between increments may be varied to suit local marketing conditions, whereas in the proportional price scheme the increment steps are iJ?-herently equal. The method of blend ".alve .control. is similar to the proportional price pump with slight vanations in detail.

Remote Indication

Remote indication was, after remote pumping and blending, the next major step in equipment development, although it had a much greater impact on the industry and was responsible for initiating the present continuing rate of development of new ideas. Remote indication, or readout, systems are based principle of separation of the components of which on the a conventional island dispenser is composed into modular units situated where they are functionally most efficient. Remote pumping is the first step in achieving this ideal, but only concerns part of the equipment. The only sections of a dispenser essential to the forecourt are the indicator and the hose and nozzle. The meter and computer can be

situated anywhere else that may be convenient and practical. However, the nozzle and the indicator would preferably be separated and placed at the rear and front respectively of a vehicle refuelling, the indicator being of sufficient size and clarity for both operator and customer to read it, the latter without moving from his seat. Also, since more than one grade of fuel is usually required to be dispensed on one island, the dispensers must be compact and closely situated. cost and complexity, ruled ;out its immediate acceptance on a large scale. Nevertheless, it remains one of the most imaginative developments of which we probably have not seen the last, which is why I think it worth bringing to your attention.

There have been less ambitious and sophisticated attempts at producing remote readout systems, based on modifications of standard dispensers. For instance, one could use a standard dispenser, with hose and nozzle and control gear removed, in conjunction with a post type hosestand operating the dispenser by remote control. The customers view through the windscreen is an improvement over conventional dispensers, although the readout cannot be compared with the sophistication of the large scale arrangement previously described. Of course, remote pumping could be incorporated in this system, as before. Special housings have been proposed which use purely mechanical control means, and it is probable that the possibilities of such systems have not yet been exhausted.

Since the actual dispensing stand need only consist of essential controls and pipework with a simple hose retraction device, space demands of this unit may be small. Alternatively, space economy can be discarded in favour of the dictates of styling.

Readout units may be single or dual units, according to the requirements for fuelling one or two cars simultaneously. Information is displayed on each dial in large and legible characters indicating the measured quantity and computed price, together with the unit price and fuel grade. When the indicator is zeroised at the commencement of delivery, the grade and unit P!ice c?ange. to correspond with the fuel selected at the d1spensmg pomt.

Using the Wayne Solo Unit, two-piston i_neter and a standard variator gearbox, a compact and reliable remote pump and metering unit is achieved. Mounted on and driven by the variator is an electrical transmitter. Information, derived from the variator and representing quantity and money, is telemetered to the remote indicator in the form of electrical impulses, and the fuel measured by the meter is pumped direct to the dispenser. All electrical lines and equipment are housed in flameproof enclosures, and the whole unit enclosed by a fibreglass housing, which is detachable for inspection and maintenance. Where circumstances justify the use of submersible pumps, these can be easily incorporated into the system to make use of their special advantages.

Blending is an obvious feature to incorporate into the remote indication system, since a considerable reduction in dispenser units is achieved. A dual blending dispenser, occupying a mere two square feet of ground area, can serve two vehicles simultaneously with any one of nine grades of fuel from the same point. Alternatively, one could offer a range of petrol fuels and diesel oil from the same dispenser, through separate hoses. Unfortunately, but perhaps not unnaturally, the advanced novelty of the remote readout system, together witb some inhibitions on Self Service

The last subject I shall be dealing with is self-service. Except for blending, development in this field has aroused more interest, especially in recent times, than any other. Historically, self-service can be traced at least as far back as the Greeks in the First Century A.D., when a coin mechanism .was described which dispensed holy water. It may have been a pretty serious thing for an ancient Greek to be caught_ short of holy water on early closing day, but equally serious no doubt to modern mechanised man to run out of petrol on his way home from a late night out. It is in respect of an emergency service on unmanned ~tations that c<;>in operated pumps can, and no doubt will, perform thelf most useful service although other applications have been proposed. '

The simplest for~ of ~oin-operated dispenser is adapted to operate on the 10sert10n of one or more coins of fixed denomination. The actual number and denomination of coins is a function of the unit price of fuel and the availability of suitable coins in respect of physical size and value. For the United Kingdom, two half-crowns are convenient, representing about one gallon's worth at current prices. At first sight there is little to distinguish the extern~I aspe~t of a simple coin-operated pump from a conventwnal dispenser, but closer examination reveals small but essential variations.

On the side of the instrument opposite the nozzle side is an instruction plate with simple operating instructions of a form approved by the Board of Trade and the Home Office. There is a slot for the insertion of coins and a return lever for coins rejected but retained in the mechanism, together with a chute into which rejected coins are returned. Also on this side of the pump is a special lock which enables the station operator to use the pump for normal attendant operation should he so desire.

On the nozzle side of the pllmp, the semi-automatic reset and motor switch levers have been combined with the nozzle support in such a way that it is impossible to operate the lever before the nozzle has been removed or to inadvertently squeeze the trigger whilst removing the nozzle.

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The nozzle itself is an approved pattern of automatic shut-off type which will terminate the delivery if the level of fuel in the vehicle tank reaches the nozzle tube, that is, when the tank is full. A further safety feature is the provision of a weak shear section in the nozzle tube which will fail in the event of a careless motorist driving away with the nozzle still in his fill pipe.

The hydraulic components of the dispenser are similar to t_hose of a standard preset pump, with the addition of an interlock valve to prevent dispensing fuel whilst the computer is resetting. The computer is automatically reset when the pump motor is switched on, the mechanism being driven from the motor through belt, chain and worm gear, although other forms of automatic reset have been used. The coin mechanism is a proven proprietary assembl~ which makes the usual checks for physical dimensions, weight ~nd composition, etc. Interlocks between the m echamsm and the computer prevent pump operation until the coins are accepted.

We haye had considerable operating experience with such eqmpment and it may now be said to be fully developed and ready to perform a useful service. However, to a. great extent, its future, as with other forms of selfserv1ce, depends on a broadening of attitudes on the part of local au.thorities in respect of the operation of equipmen~, provided with reasonable safeguards, by the general pubhc on unmanned stations.

A mu~h 1!1ore sophisticated system designed to extend tI:ie application of coin operation beyond emergency service t<;:> a completely unmanned twenty-four hour service on cot~ laundry lines has attracted interest. This utilises a mult1-denomi.national central coin mechanism serving a bat.tery of dispensers. There are facilities for grade s

electi~n, t.he acceptance of any number of each of three deno~mattons of coins, and receipt issuing. This arrangement involves electrical and electro-mechanical memory and telemetering systems controlling the dispensers.

The principal modifications to a variable preset dispenser. are the preset selection by means of a rotary solenoid .and two signal lamps prominent on the top of the housing. One lamp flashes as credit is transferred from the ~entral control unit on acceptance of the coins and selectrnn of a grade and the other is illuminated when the transfe.r is complet~ and the pump ready for use. An att:act1on of the central coin control from a safety aspect _is .that it may be located in a non-hazardous area, thus ehmmating the necessity for providing expensive and bulky ~a. meproof housings. From coin operated equipment, tt ts a short step to bank note operation to further e~tend the whole idea and enable a motorist to fill his tank with ease, speed and facility.

From self service of the unattended variety, represented by c~sh or credit controlled system, of which I have only ment1~ : med the former, we pass to attended self-servi~e. By th~ s I .me~n the type of equipment where the motonst, f:o.n~

rn.clmat10~ or by incentive, takes over some respon?

1~1ltty tn the dispensing operation, but where an operator 1s in attendance. "Self-Fill Post Payment" is the term used to describe the m?st popular form of attended self-service, it having been in widespread use in Sweden for some time, and lat~er_Iy in the United Kingdom and other coun.tries too. This 1~ a central control system for a battery of d

.1 s pen~ers

, but with the essential difference that the control 1s entirely within the hands of a practised, though not necessarily skilled, operator housed in a conveniently situated ·kiosk. In addition to physical control over.every phase of pump operation, the controller may also be in voice communication with each dispenser, as required.

The essential control unit comprises as many identical individual modules as there are dispensers, each module consisting of a display of slave counters, repeating the quantity and cash values registered on its corresponding pump, start and stop buttons, and a manual control key at the rear. The addition of a master intercommunication unit does not affect the telemetering and control function. Installation wiring is more complex than conventional power supply and lighting networks, but not without the capacity of competent electricians. Each dispenser is individually wired to a control module in the remote console, except for the intercom system, which is simplified thereby and entirely adequate.

The only variations from conventional dispensers are the addition of transmitters for basic registration data and microphone when required. Fully automatic reset may also be provided. The dispenser intercom unit takes the form of a small combined microphone and loud speaker incorporating a call button. It may be installed within the dispenser housing, or attached externally.

A prominent instruction notice of approved form is displayed near the controls and invites the customer to press the intercom call button if in difficulty. This action alerts the controller by an audio and/or visual signal on the master intercom unit and also identifies the dispenser concerned; automatic nozzles are invariably supplied with this equipment as a safe guard.

Several types of transmitter have been used, one de~ign being a photo-electric device in which perforated discs, driven by the cash and quantity output sh~fts of the computer, interrupted light beams to photo diodes. The whole being contained in a ftameproof .e~clo

s

u~e. . An improved form of transmission uses alumm1um discs u:ito which are set a number of permanent magnets which actuate reed switches. Due to the nature of cash computation, it is necessary to drive the cash transmitter from the computer counter shaft. Ho.weve~ , more accurate quantity registration can be obtarned mdependently of the computer by driving direct. ~rom the I?-eter output shaft. Counting speed and defi111t1on are entirely dependent on the slave units at the present stage of development, being of the order of one hundredth of a.gallon increments of quantity and halfpenny monetary units.

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A recently opened station operating the post payment self-service system demonstrates some advanced features of design and operation, with a central glass sided building housing the control console, cash register and accessories and general goods shop. The control console in this case has space for an additional slave unit for the registration of sales from an oil dispenser. Dispensers are arranged on two sides of the central building consisting of three dual and one petrol-oil mixing dispenser. The petrol/oil dispenser is interesting as a development in its own right. Unfortunately, I have not covered this field in my text and there is not time to dwell on it now. Suffice to say th_at it is similar in principle to the petrol blending pump with one of the base products being two-stroke oil.

Preset Controls

One advantage of direct cash or credit control systems, which may easily pass unnoticed, is that the manual control function of the nozzle, by reference to the registration, is eliminated for the customer. bemg_ automatic and consequent on such equipment with preset devices of various degrees of soph1st1cat1on. The development of automatic control by this must surely be a future trend, and I shall now consider the past development and possibilities for the future.

The standard preset quantity selector, setting up a cam and pawl operated device in the computer in increments of half a gallon up to ten-and-a-half gallons, is well known. _n:10re well known is a simplified, fixed, form used as a device in areas where local regulations require the lui:iitmg of non-interrupted deliveries to some arbitrary quantity safety reasons. Not so well known is the fact that a similar device for presetting in monetary units presents no difficulty. Both rely on the computer to operate a valve in the flow line to terminate the delivery. it is not so simple to combine the two to offer the choice of presetting in cash or quantity on the same pump. Also, although easily carried out by an experienced operator, _the sequence of operations is rather more compl_ex than 1t would be wise to expect a customer to perform ,, practice. It therefore becomes necessary to simplify the preset function, by means of push buttons or telephone dial type controls, to enable variable presettmg to take its place in self-service and other develop-ments. d We have investigated many solutions and are currently relopmg '.'l push button unit permitting the presetting 0 one to nmet _y-nine units of quantity or m<;>ney the con!rol. fn addition a tank fill facility is available, t e cessation of delivery being controlled by an automatic nozzle. A cancel button to enable setting mistakes by the user to b b e · rectified ' completes the arrangement. All when depressed for clari_ty i.n poor light circu'l!stances. Preset shut-off of 11qrnd flow ispenser is achieved with the use of two solenoid valves, one of large bore for full flow, or primary ut-o ' and the other of small bore for fina! shut-.off. ?ntrol of these valves is by means of a steppmg switch pi eset m control unit by the action of the buttons. J he stepping switch is actuated by means of transmitters n.ve n_ by. the counter shafts for money and q Llctnti ty 1 espect1 vely. The transmitters are of the camoperated and micro-switch var.i ety and robust and reliable.

One application of this system is to speed up forecourt attendant service, particularly with the enlightened advent of automatic nozzles fitted with trigger latching devices, which as you know, are presently forbidden in this country. Another application is as an additional feature to the post-payment self-service system. Other ideas would include pre-payment self-service, which I have not previously discussed, primarily because this only becomes feasible with remote presetting.

All aspects of self-service so far discussed have involved the customer in handling the hose and nozzle and, in some cases, considerable ingenuity and no little trouble has ·been exercised in simplifying this operation. You will not be surprised, I am sure, if I introduce as a finale a system where the customer takes over the select and reset functions of dispenser control and leaves the nozzle handling business to a forecourt attendant.

Such a control unit would preferably be compact and enable the to stay in his, or her vehicle. Smee the telemetenng problem is the same in priqciple, whether it be blend selection or money presettmg, one solution solves both problems and the system has been designed to be used in conjunction with an increi:nent price blending pump. Accordingly, the control box mcludes facilities for blend selection and monev An positi?n on the money selecto.r provides for filling the tank with an automatic nozzle. The only other controls provided are start and emergency stop buttons. Slave counters indicating quantity and moJ!-ey the customer what he is getting without strammg his eyesight. The manual blend selector knob and interlock lever on the normal blending pump are replaced by a reversible motor, geneva movement and solenoid. Together with solenoid operated control valves, these are the only modifications to the standard dispenser.

In operation, the station attendant resets the computer, operates the starting lever and places the nozzle latched open, into the fill pipe of the car. He then the control box to the customer, pointing out the instructions printed on the box, and departs to attend to other matters. The customer then sets up the controls, depresses the start button, and watches the counters ticking round. On completion, the attendant returns, removes the nozzle from the car and replaces it on the pump and, presumably, the customer pays the attendant for the pleasure- or is it the other way round ?

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