Gents,
thank you for all the replies. I do agree that AC seems to make the most sense and the cheapest option here. With a DC servo the PSU needs to be rather huge, there's the driver and on top of it all the gearbox. Main issues with AC are size and noise. I might need to have a second look at...
Hi zekeman,
thanks for your input.
Your way of thinking is roughly the direction I was going in. Get a brushless DC motor / servo and couple that with a gearbox (was thinking planetary 10:1 or 15:1). The main problem was:
1. DC power supply - mostly due to the amount of current needed by the...
Hi Bill,
10-12Nm is what I managed to measure on one occasion with a torque wrench and this was with a jam-up, so effectively the maximum torque required.
The shaft is 25mm, body is 15mm ali, should take quite a lot of abuse before things start falling apart.
To be honest it's hard to get a...
Gents,
thank you for all the help so far. A bit more detailed info on the requirements, to answer zekeman's questions
1. how fast you need to perform the task
I thought 250RPM covers this, this will effectively limit the speed of operation
2. how often
This varies, I'd say every few...
Gents,
again, thanks for taking the time to reply.
I've looked at the robot stuff, actually I have a robot brushed DC geared motor, which can do 2.3Nm max at 480RPM and I can squeeze a 2.5:1 ratio done via HTD 5mm pitch 15mm wide. What this means is I get around 6Nm at around 200RPM, which is...
Hi KllrWolf,
thanks for taking the time to reply. Here's more info, which I should've included in the original post:
- AC or DC, doesn't matter, but I'd rather have a quieter motor, which I think steers this into DC direction.
- with DC it would be preferably 24VDC, although 12VDC and 48VDC...
Hi everyone,
can someone recommend a motor solution to achieve 250RPM at 12Nm ? I'm looking for an off-the-shelf solution and the least amount of parts / devices involved. Torque requirement is momentary, I don't need 12Nm constant running torque, more like peak torque for 1000ms or so...
Hi everyone,
I'm working on a machine which is mounted in an L shaped enclosure and I'm wondering which of the following configurations is more stiff:
The left one is a config with two up-side-down L parts being the sides and multiple rectangle shaped parts locked between it. The right one...
...supply line might not be so great though, but still stable throughout longer periods of time (cold tap water supply). I'd be aiming for around 0.5*C accuracy.
The thing I'm worried about when using the 'cool down' approach (adding cold water to the hot water) is that it won't mix properly...
...which is basically changing the output water temperature quickly by adding cold water to a normally hot water line. I'm looking at a range of 88-94*C, flow rate of around 180ml-300ml when the whole process takes roughly 30s. The hot water line is driven by a pump which has a variable speed...
...cut-out to further protect the boiler from explosion in case of a failure of any of the above. The boiler will be filled with water and set to 93-95*C and simply used to dispense water at a steady temperature (around 90-93*C).
Is there anything else that I need to add to make sure it fails...
...safe, right? Sure those protection devices can fail and it will blow anyway, but anything an fail really. In idle mode it will be sitting at 93-95*C, the 9bar pressure will be applied from time to time for around 30-40s not more, so it won't be at full 9bar pressure all the time.
Thanks for...
Hi guys,
the boiler is going to be fully filled with water as it's going to be sitting at around 93*C-95*C, so I can't really put a relief valve on it, other than an OPV. Water under 9bar of pressure will be moved through the boiler, so it's mostly going to act as a heating device (to disperse...
Hi guys,
thanks for the tips!
Ok so to sum up:
- the second switch will be a 16A sealed switch (just for additional protection as it might operate in a wet environment) and will be used to trigger the heater power supply loop.
- there is an over pressure valve and a check valve between the...
Hi guys,
I've got a 2kW heater which is controlled by a PID done using a suitably rated SSR (actually a bit over-the-top one as it's 50A, but I didn't want to buy another lower-rated one). This is inside a machine which has other PID controllers, two solenoid valves and some electronics, all...
Thanks Graham, I've actually decided to mount the boiler slightly suspended, so that the only point of contact are the M10 buts/bolts holding it. It's not heavy and this should work properly.
Regards,
Tom
...30cm wide) on a small frame made out of 1.5mm stainless steel flat and L shaped pieces. Because the boiler is going to be heated up to around 95*C for quite a while I’d like to put something between the boiler legs (two flat legs around 20cm long and 5cm wide, so contact surface is 100cm^2...
Hi guys,
yes there is a small kink/crank in the top part of the thread which is what causes the tape rip and leaks. I guess there's no other way than liquid sealant, although I will wait and see what the company technician says.
Regards,
Tom
Hi Latexman,
yup definitely NPT, it even says so in the manual. I'm still not sure why the manufacturer of this pump (Fluid-o-tech) doesn't recommend liquid sealants.
Regards,
Tom
Hi,
nope no way to correct that as I haven't got the tools. Plus it would probably be quite tricky without getting anything inside the pump.
Regards,
Tom
