Loctite info thread

Loctite 271 Stud lock High Strength Threadlocking Compound. Red version of Loctite 270(green)

source

 

Loctite 262

Recommended for a wheel stud conversion, here.



Loctite properties:

Loctite 262 Threadlocker is a permanent threadlocker for fasteners up to 3/4" (20 mm) in diameter. Excellent for preventing rust and corrosion in extreme chemical/environmental conditions.

Further digging through technical datasheet:

Strength listed as "Medium to High"

(243 = "Medium", 270 = "High", 271 = "High")

 

Speaking to our supplier at work recently I found out some interesting info as to why there are so many different products for what appear to be the same applications.

A lot of it depends on what material the fasteners are made of. Obviously some metals are porous, and so would `soak up` the Loctite. Others may also affect the cure rate. These would then of course reduce the effective strength of the locking compound.

There are therefore several different compounds depending on the material being used (mild steel, stainless steel, brass, zinc coated, etc). That`s why it can be such a mine-field trying to decide which product you need.

Then you have the envriomental conditions of operation to take into consideration too, which adds even more choice!

The longer the compound is exposed to certain oils/chemicals the less strength it has over time.

He also recommended using an activator before application (though we don`t bother with it). It is designated `7471`, and apparently speeds up cure time, and also helps the compound retain its strength over time.

Basically, for automative applications where everything is steel, 243 is fine for medium strength where there is no excessive heat (ie, just about everything bar internal engine/transmission fixings) with 270 being used for `permanent` or high stress applications (ie, flywheel bolts, main bearing caps, diff bolts, etc)

246 is what you need for high strength/high temp applications. (ie, brake components, clutch pressure plate, etc)

 

True. Like I say we don`t use it.

Mainly because the process of applying it and the cure times are so critical.

In manufacturing this is fine, when a component can more readily be left to cure fully, but for us in a maintenance enviroment simply don`t have the time, nor can we risk the compound not curing to full strength due to improper application.

 

Found an interesting Loctite summary in an old TRC magazine, written by Andy Dawson, who is ex-WRC / an engineer.

All versions already mentioned in this thread underlined in red. I think the first one is meant to read '242'? Edit: no, saw it somewhere else so ignore that: it's right.

 

Something I found the other day at work, might be of use- probably not though!

























Although 243 is listed as 'Medium' we use it for our dyno torque hubs at work- 1100Nm+ and alot of stresses when motoring etc - it does the job just fine, also operating at the higher limits of it's temperature range. I'll be using this for my wheel studs unless I can find some 270 knocking about.

 

Useful addition, defintely - broadens what we'd already got: 577 and 603 mentioned in the 'motorsport' TRC-originated table above, and 660 worthy of note + all the adhesives listed.

I'd not recommend 243 for studs, from experience. It might be ok for work, if it's dismantled often. 270 minimum.

 

Chris- did you find the 243 didn't hold the stud? We use 270 aswell, but find it very hard to remove anything once it's gone off... hence employing the 243.

It's a vaild point that studs don't need to come out (except possibly to change a wheel bearing) 270 deffinately seems more 'fit and forget' than 243.

 

I don't think I ever tried it - it's just 243 being labelled 'screwlock' and 270 'studlock' seems to give the reqd. indications.

270 IMO is marginal - ideally I want more strength. Wheel guns eventually break them loose.

My guess is if you're dismantling often at work, then that's why 270 isn't fancied.

 

Picked up some loctite today in 2 variety 243 and 271

Which one would be better suited for bolts on compressor side of the turbo?

in past couple bolts holding wastegate actuator worked them self loose

 

If any 271. A quick search and it appears to operates to 300 degrees C.

I thought it was 150 - Loctite 270 is 150 IIRC - so double check.

 

Use Loctite products a lot at work. Find these really handy.

http://www.loctitesolutions.com/files/AN09/Solution Guide issue 6 12.08.08.pdf
http://www.loctitesolutions.com/files/AN09/Solutions for Vehicle Repair and Maintenance 2009.pdf

As a cleaner Loctite 7063 is awesome stuff!

 

The basic Loctite grades are as below: (This information is from the Loctite Technical Departments in US and UK. Recieved yesterday)

RED was USA grade high strength thread locker which became 271 (the red version of 270) - STUDLOC

GREEN was UK high strength thread locker which became 270 - STUDLOC

BLUE was medium strength thread locker which became 241. 243 is the new improved version of 241 - NUTLOC

PURPLE was low strength thread locker which became 221. The new improved version is 222 - SCREWLOC

No matter the number, you can safely work from the colours alone:

RED/GREEN = HIGH STRENGTH
Loctite state that it is designed for the permanent locking and sealing of threaded fasteners.
They do say that disassembly is possible by heating up to 250C/300C. 2620 and other special high temperature products excepted.

BLUE = MEDIUM STRENGTH
Loctite state that it is designed for the locking and sealing of threaded fasteners which require normal disassembly with standard hand tools.

PURPLE = LOW STRENGTH
Loctite state that it is designed for the locking and sealing of threaded fasteners which require easy disassembly with standard hand tools.

The standard products: 270/271 - 243 - 222 all require 24 hours curing to reach full strength.
Actvators are available to speed up the curing process.
Work on the principle that all nuts and bolts should be clean before applying Loctite.

Post or contact me if you want more information. I have downloaded all of the important data sheets from around the world, and the contacts at Loctite say they are willing to advise on specisl applications.

The other numbers are for special applications or for different countries.

Below are examples:

225 is BROWN and is graded as Low/Medium strength. It is in between SCREWLOC and NUTLOC.
248 is BLUE and is graded Medium strength. It is a wax stick that you can use overhead.
268 is RED and is graded High strength. It is a wax stick that you can use overhead.
290 is GREEN and is graded as Medium/High strength. It is low viscosity and will creep into already assemble fastenings. The product can also fill porosity in welds, castings and powdered metal parts.
2400 is BLUE and is graded Medium strength. It is designed for stainless steel and plated surfaces.
2432 is BLUE and is graded Medium strength. It is designed for titanium surfaces.
2620 is RED and is graded as Medium/High strength. It is a paste and designed for extreme high temperatures.
2701 is GREEN and is graded as High strength. It is designed for hot oil conditions.
2760 is RED and is graded as High strength. It is suited for heavy duty applications such as bolts used in transmissions assemblies where heavy shock and stress levels are encountered.

 

A very useful distillation of the complex Loctite product range and importantly the history. Thanks, appreciated.

Just to clarify these:

Is the 271 sold in the UK and is it green or red?

To my mind, UK 270 is green (and possibly UK 271 aswell if sold).

Are you saying the USA never got 270, so they had "Red" which then became "271" (red?), bypassing "270".



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2701 is sold in Halfords (you have Halfords, in Eire?). What exact comparison does this hold against UK 270/271?

Appreciate it - this is very useful.

 

This quote is cut straight from the Loctite UK missive.

As I read it RED and GREEN were virtually identical, one for US and one for UK. When they numbered them they put 271 on the RED and 270 on the GREEN. I only have GREEN 270 in my shed, and this is over 10 years old. From the above, the present 271 is improved on the previous 271s and 270(?). In what way it is improved I don't know. Both appear to be current, as there are up to date data sheets for 270 (Aug 2009) and 271 (Jan 2010)
It gets awfully complex Chris, as form the data sheets 270 seems to offer much more tolerance for use on stainless steel and oily threads, but it cures more slowly.

I am quite willing to get back to them to clarify.

The list below the first statements: RED/GREEN (HIGH) - BLUE (MEDIUM) - PURPLE (LOW)
Seems a good basic approach.


270 mentions its tolerance for use on stainless steel - breakloose torque = 46 NM
271 makes no particular reference to any areas of usage - breakloose torque = not quoted
2700 makes no particular reference to any areas of usage - breakloose torque = 34 NM
2701 mentions its capability in hot oil conditions - breakloose torque = 30 - 60 NM

As I mention to you before Chris, there is no consistancy in the way that Loctite present the data in the sheets. Their quote to me when, I raised this point was: "Differences in our data sheets arise for a number of reasons these include but no limited to has a product been developed for a specific market or market segment (in US they use imperial measurements in Europe metric), during development has a customer paid for specific data to be included & so on. Also new products are developed to address specific market needs such as loctite 2400 which is a medium strength threads locker with no health & safety labelling. In Europe we are in the process standardising our test data to give comparable results but this take time & money."
Grammer as recieved!

 

I think this is the one o/s question - if possible, can this question be channelled in?

 

I will get back to them on whether 271 is available in the UK. I don't see why not, grey imports happen all of the time. Officially perhaps not.

Thinking back to the 1960s, I only remember RED and BLUE. At Laycocks we used RED on the studs into the overdrive main housings and BLUE on the nuts fixing the tails onto the main housings. No numbers then! I also believe we used RED on the nuts of the thrust bearing yoke, as loose nuts would have destroyed the whole unit, and a new thrust bearing yoke was cheap enough to destroy on a re-build. We had big bottles over the assembly lines. I used to nick it in jam jars! The colour difference may well be due to national Health and Safety Regs. I will check this on Monday. I have not downloaded H&S regs. BORING!

As I read it now: 270 is always GREEN and 271 is always RED, and they are basically identical. Again I will check on Monday.

 

Thanks Dave. Tidied up and await that v. useful clarification.

 

Just to un-clarify a bit more. In the 1960s, all Loctite products possibly came from the USA. Only companies like Laycocks knew about them in the UK. I don't know when H&S regs came in, perhaps the different colour, GREEN, came in at the same time? I shall sort it!

 

Second thoughts, memory lapses!
The big bottles over the line may have been brown joint sealant, a bit like treacle, this we did purloin in jars. It did a similar job to 'Hylomar' (also available in blue and red - don't ask).
The Loctite was probably in smaller bottles, 8 or 10 fluid ounces, and only used in certain types of unit. Possibly to seal where a tapping broke through into the main housing, to stop oil leaks? I think it was quite expensive at the time and quite closely monitored. Some of the small set screws, holding cover plates on to the housing, were cross drilled with small holes and were locked in position with locking wire. This may have been replaced with Loctite? We also used various torque prevailing nuts, in various places, on different designs. I am trying to think if Nyloc nuts were available then. Anyway, some of the internal nuts were thin due, to space restrictions, and Loctite would be used there.
All assembly was performed with Desouter air tools, with fixed torque settings. Every setscrew and nut was torqued accurately and quickly with these. Unlike the ones used in tyre bays.