Vacuum Truck Supplies

Answers to FAQ, organised by topic:

General Information about VTS and Building Vacuum Tanks & Trucks

How long does it take to build a vacuum tanker?: It depends on the complexity of the project, it could take from 3 weeks to 20 weeks. VTS quite often have stock units or have access to customers who wish to sell second hand tankers.
How much does it cost?: Again it depends on the complexity. It could be as little as $15k up to as much as $300k or even more.
Can you build any size tank?: Sure can! We have a number of standard size diameters that we work to and fit all size tanks comfortably into them.
What qualifies VTS to build vacuum tanks?: VTS have been building vacuum tanks for over 20 years now. All VTS tanks are fully engineered to the relevant standards by a qualified Mechanical Engineer and they either meet or exceed the relevant Australian Standards. VTS also has its own internal drafting and design department which makes use of the latest computer 3D modelling tools.

Choosing the right machine

What size vacuum pump should I fit to my truck?: The easy answer is: the one that will do the job quickly and efficiently! Usually VTS will ‘over spec’ a pump/tank combination to allow for flexibility and growth into other areas – we call this future proofing.
What is the best truck to use for my next vacuum tanker?: That depends on a number of things – preferences, budget, existing fleet, and the nature of the job to be done. For example, a 7000 litre tank and allied equipment to do general liquid waste will require a 4×2 15/16 tonne GVM cab chassis. 10000/11500 litre tanks will require a 6×4 22.5 tonne GVM cab chassis. As for the budget – second hand trucks often cost more than buying a new truck when you consider the monthly payments.
Which is the best type of vacuum pump - liquid ring or rotary vane?: This depends on what is important to you. Vane type pumps are long established in the Australian liquid waste industry and are easy to maintain but can be can be smoky and noisy at times. Liquid ring pumps are gaining popularity because they are quiet, more efficient and don’t use oil, however they are more complex and require more space and water to function properly.
To line or not to line?: All linings, no matter how expensive or how well applied they are, will delaminate where product comes into contact with it. Velocity and the weight of product will eventually cause the lining to wear back to the substrate. Once this has occurred, the lining will delaminate around the penetration. This allows products to mix and a perfect corrosion environment becomes well established. This will enhance the delamination process and speed up development of a thin spot in the tank wall. I have seen relatively new tanks (which have been lined) as thin as 1.5mm where this has occurred. Essentially the tank could not be repaired and had to be decommissioned. In short, lining vacuum tanks is a false economy.

Normal Usage & Common Problems

How long should it take to build up vacuum?

That depends on how the pump and tank combination work together - the larger the pump, the quicker the operating vacuum levels will be reached. A 7000 litre tank with a 350 CFM pump will get to 50 Kpa in around one minute.

Why does my vacuum pump stall when I start pumping?

A stalling pump usually indicates a horsepower deficiency. Give it more HP and it will perform faultlessly. That doesn’t mean more RPM; the gearing may be incorrect.

Why is my vacuum pump noisy?

There could be a number of reasons, heat = swollen vanes, contamination = sticky vanes and internal damage to the housing, low or no oil, low or no water levels in the separator. If the noise level is not not what it is normally, STOP and check into it. This will stop you spending money on fixing a problem that may have been avoidable.

How can I stop froth from entering my vacuum pump?

Here are some suggestions to minimise the risk of froth intrusion into your Wallenstein (or any other pump for that matter):

Load through the dump port
Build vacuum in the tank, reduce pump rpm to just above an idle to maintain adequate loading vacuum
Fill tank with 100-200 litres of water and then load through the dump
Fit an additional secondary to allow the froth to liquefy
Fit a misting nozzle to the load port or on the suction hose to liquefy the froth before it gets to the tank
Treat the product/froth with an antifoaming agent
Minimise the amount of agitation to the product
Use an auxiliary pump to load the tanker, trash pump or the like
Use two trucks in series with one as the waste tank and the second as a secondary
If you have a tipping tank, tip it up to increase the vertical height the froth has to travel
Gravity feed into the tanker if levels allow
Fit a transit valve to the primary shut off, manual or air operated
If nothing changes ensure you are charging your customer enough to allow for frequent end plate disassembly and thorough cleaning

Dairy waste and abattoir/blood (and obviously food) wastes are notorious for frothing/foaming. Any or all of the above have been tried and some/most work in some way, shape or form.

Maintenance

How can I make my vacuum tank last longer?

The value of a vacuum tanker (apart from the truck) is in the tank so it makes sense to look after it with regular cleaning, inspection, testing and servicing. Generally speaking, the following should be observed:

Always make sure a tank is thoroughly cleansed when changing loads
Avoid mixing loads (cocktailing) this is dangerous and causes undue wear to the tank (this is especially true of acids)
Clean every nook and cranny, behind the baffle and around the manways
If a tank is to be taken out of service for a period of time longer than a couple of months, fill it with water to the absolute brim and then close it up. An air free environment will prevent corrosion.
Conduct the following regular inspections and tests:
- 3-month external visual inspection of all welded seams, hinges, manways, mountings etc. for all tankers carrying toxics and corrosives and hazardous goods
- 6-month external visual inspection of all welded seams, hinges, manways, mountings etc. for all other tankers
- 12-month internal inspection of baffles and any internal fittings for all tankers carrying toxics and corrosives and hazardous goods
- 24-month internal inspection of baffles and any internal fittings for all other tankers
- 24-month hydrostatic test for all tankers carrying toxics and corrosives and hazardous goods
- 24-month ultrasonic test for all tankers carrying toxics and corrosives and hazardous goods
- 48-month ultrasonic test for all other tankers
Note that:
- AS2809.1 2008 Section 3.1 calls for a 3 monthly inspection although it doesn’t call up an inspection standard, this standard is for any tanker constructed to comply with AS2809
- AS1210 doesn’t specifically refer at all to any ongoing inspection regime.

What is normal wear and tear?

A vacuum tank will wear around the bottom 1/3 of the barrel and also around the lower rear head. Load ports and dump ports will also wear. Any point where there is a bend in the loading path of the waste will wear due to velocity and abrasive nature of the waste being loaded. Lining vacuum tanks is a false economy.

Definitions

What is a vacuum?: According to Wikipedia – a vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure. The word comes from the Latin term for “empty,” but in reality, no volume of space can ever be perfectly empty. A perfect vacuum with a gaseous pressure of absolute zero is a philosophical concept that is never observed in practice. Physicists often discuss ideal test results that would occur in a perfect vacuum, which they simply call “vacuum” or “free space” in this context, and use the term partial vacuum to refer to real vacuum. The Latin term “in vacuo” is also used to describe an object as being in what would otherwise be a vacuum.
In our terms a vacuum is what happens when a pump sucks the air out of a tank.
What is air flow?: Air flow in relation to a vacuum truck is what happens when the vacuum pump generates a noticeable movement of air when a valve is open from start up. It is this movement of air that is capable of moving product. The more air, the greater the speed and weight of product shifted. Air flow is not vacuum and should never be confused as such. Even the smallest vacuum pump will be capable of pumping out a septic, it’s just the time taken will be longer…

Frequently Asked Questions