Will a budget trough type pressure test pump do my hydrostatic pressure test job?

I need a pressure test pump. Will a budget pump do my hydrostatic pressure test job? How do I move on if it won’t do the job?

The answer is maybe one of the dozens of stock units online will do the job. We have got our budget MZ unit there as well. Let’s dig a little deeper into what you need. Let’s see whether a budget trough pump will do your job. And where to look if you need more.

Where do I buy a budget trough type pressure test pump?

Look at a mass market catalogue like Screwfix, big industrial factors like Zoro or even the mega suppliers like RS, low pressure pumps are there. You have basic water duty, low pressure and fitted with a pressure gauge. As professionals, we probably aren’t fans of scrolling through endless Far Eastern clones. Some are amazingly cheap. Time is money and professional tools have to work today and have a decent service life in the shop.

So, what are the basics on a pressure test pump and what sort of unit would you simply buy on line or over a trade counter? Would something like the Rothenberger RP30 do the job? At what point is a pressure tester a little more complicated?

What fluid am I pressure testing on?

Fluid is fundamental. That’s where we would start. The mass market is water pressure test pumps for testing pipework and systems. Plumbing and “test” pumps would invariably be water. That’s easy. But if on day one, you need mineral oil, then maybe the mass market trough units aren’t for you. We wouldn’t assume the pump is happy on oil and we aren’t sure the trough reservoir works nicely with oil if the fluid is slopping around. We offer a range of mineral oil pump units to meet a range of needs. We suggest a pump with integral reservoir like our MP-A series. Or pick an industry standard pump with a tubular reservoir for oil. In the wider market, 700 bar units like the little Enerpac P141 are neat and we use one in our shop, but be aware these pumps are invariably for connection to high pressure cylinders. Most of this type need an extra fitting to tee in a pressure gauge. That has always seemed messy especially as the outlet port is 3/8npt female, an NPT tee is easiest but mass market UK gauges are 1/4bsp. Fixable, but a chore. Our own PMP is tubular and has an in built 1/4BSP gauge port and gauge option.

Pick a more demanding fluid like brake fluid or a glycol and you need advice. You might run happily on anodised alloy or move to stainless steel.

What is the best reservoir for a pressure test pump?

A trough construction is most common and a starting point on entry level water test pumps. Again, easy to use and what the plumbing and test pumps work with. It is the cheapest option. You put your foot on the tank to stabilise it. That works at low pressures. Probably 5 to 10 litres capacity. Cheap units still use steel which will corrode but be mighty strong for shop or site use. A plastic moulded reservoir is very light, cheap and corrosion resistant but hopeless if it gets seriously squashed and cracked, subject to the plastic used. Our MZ trough pump uses a 9 litre lightweight corrosion resistant stainless steel reservoir for durability. That is quite bullet proof. Contractors have run them over with a fork lift and then made something serviceable again. Reservoirs are our speciality, from 1 litre to 100 litres. On reservoirs, you probably get what you pay for. Are the lovely moulded plastic reservoirs used by the automotive industry and on small power packs very helpful in providing a cheap reservoir? They look so good. These are available as catalogue items, but we have had limited success with them. You need connections in the right place and careful design is required if the structure around them is under load. Nevertheless, a product like our marine panel pump or sub miniature marine pump are based on a connection to a remote reservoir, invariably a moulded plastic unit. Motorsport use a wide range. So, a great product in the right application, but not your pressure test pump.

We offer a range of mineral oil units to meet a range of needs. We would go pump with integral reservoir like our MP carry-around with a base plate or our PMP tubular unit. Or pick an industry standard pump with a tubular reservoir for oil. 700 bar units like the little Enerpac P141 are neat and we use one in our shop but most of this type need an extra fitting to tee in a pressure gauge. That has always seemed messy. Our own PMP is tubular and has an in built gauge port and gauge option.

Pick a more tricky fluid like brake fluid or a glycol and you need advice. You might run happily on anodised alloy or move to stainless steel.

Would it be cheaper to buy a pump and sort out my own reservoir?

People used to buy pumps years ago and “knock up” a reservoir. It doesn’t seem to be done now. We think it is inevitably more costly. We would say buy an integral pump and reservoir, picking the reservoir to suit you. Unpack the unit, fill it with fluid and start testing. Reservoirs are 1 litre to 100 litres in our catalogue.

Why does test pressure determine the type of test pump?

Pressure is also a key figure. Mainstream units are low pressure, say working up to 50 bar. If you are testing a misting fog system to 15 bar, a mass market Rothenberger trough pump will be fine. They do higher pressure models as well. Take the pressure up to 110 bar or even 300 bar for higher pressure misting systems and you need something more specialist. Coupled with that is displacement. You will have a compromise on displacement, pressure and handle load. At 100 bar, it is probably worth giving this some thought. Your system volume is key, as you won’t want to be pumping massive numbers of strokes. Our own units run on up to 1000 bar with variations of type. The very simplest pumps are “single acting”, just pumping pressure on the down stroke. Cheap trough pumps don’t seem to be offered as ‘double acting” hand pumps that pump on the up and down stroke. That is inevitably more expensive but offers something for nothing in that you can shift twice the volume. That said, an upward handle effort only works for users if the reservoir has a decent foot plate. And it is possible that the job doesn’t justify more than a cheap single acting hand pump. Don’t confuse “double acting” with a sophisticated two speed hand pump with rapid large-volume refill and a smaller volume high pressure stage. Double acting can also refer to a pump fitted with a four way directional valve for double acting cylinders. If you need to navigate through single or double acting and pumps, two speed or pumps fitted with four way valves, we are the experts. We manufacture all permutations.

Our two speed test pump PSP offers rapid prefilling and 6 models up to 1000 bar.

Always keep in mind that you can prefill your test piece with mains water then just use the hand pump to bleed out the air at the highest point then carry out the test. Prefilling cuts out lots of pumping to fill.

What sort of pressure gauge is needed on a test pump?

Pressure gauge is fine until you are fussy and don’t want a cheap dry gauge or you need a calibration certificate. Or maybe the sheer hassle and cost of sorting out a cheap gauge that fails is intolerable in your shop. Quality people will invariably tell you that a gauge that isn’t calibrated is of little value. Otherwise, you are using an “indicator.” Removing a cheap gauge on a mass market unit might be an easy fix or not. We have standardised on G1/4 gauge stems and fittings. NPT also works for us, provided you are aware at the time of ordering. One extra adaptor is required.

Why can a cheap pressure test pump be troublesome?

Finally, does the unit work? We have tried cheap units where the pressure won’t shut off. We aren’t great fans of brass fittings, but those are widely used on cheap plumbing pressure test units. Our Micropac test units have always used a poppet pump check valve with an o ring in it. You need the pressure to stay pumped up once you are at test pressure so you can be sure that a leak is in your components, not the pump. Some test pumps do add in a second shut off valve, but this needs to be upstream of the pressure gauge or you can’t tell what the system is doing. If people need to “lock off” pressure into the stem to be 100% sure, we offer this as a separate little module to be added into a system.

Do you want to be able to buy cheap spares in the future?

You may need a throwaway pump for a job. The unit may be in use daily. Or you store it and want it to work in six months. We offer low cost spares and have always been keen on soft seat inlet check valves so the ball doesn’t stick after a few months on a metal on metal seat.

What can Sarum Hydraulics / PumpShop Pro offer me?

PumpShop Pro is the online distributor of Sarum Hydraulics equipment.

Pressure test pumps and hydrostatic testing are quite specialist. We are the experts. Look at our products and technical resource on our website. After over four decades of manufacturing our Micropac hydraulic hand pumps, we are always pleased to discuss applications for our pumps. Contact us.

For technical enquiries, contact us at Sarum Hydraulics.

For browsing and buying Sarum Hydraulics products online, use PumpShop Pro.