Brodie helmets, Heat numbers/Batch numbers

[GRANVILLE]

The manufacturers marks stamped onto the underside of the rim of a Brodie helmet, has formerly been referred to as s heat number; something which I personally did not understand, having no experience of the steel industry and also never having come upon any contemporary reference to this before. Once you become aware that some helmets bear higher numbers than others e.g. HS 37 as opposed to HS 87, the door is open to ask why and what does it tell you. Using simplistic logic, I personally have tended to assume it must mean that HS 37 is 'batch 37' and HS 87 would naturally be 'batch 87', from which then follows the presumption that batch 37 must be earlier than 87? To me, there remains a certain amount of logic to this, as unless one batch can be identified from another, I could never understand how a helmet could be recalled if the steel it was made of proved to be defective in some way?

As I say, I have never come across a contemporary reference to this subject, however this is no longer the case because in this publication, written in 1920, certainly heat numbers are mentioned.

Helmets and Body Armor in Modern Warfare by Bashford Dean PH.D. Curator of Armour, Metropolitan Museum of Art U.S.A. and formerly Chairman of the Committee on Helmets and Armor, Engineering Division of the National Research Council U.S.A.

Clearly, this man will have know what he was writing about and on p130 of the book, he writes the following:

The manufacturer was required to demonstrate that his product was proof to shrapnel ball, forty-one to a pound with a striking velocity of 700 foot seconds. This test was given to ten helmets in the first thousand, three helmets in the second and third thousand, and two helmets in each succeeding thousand. No requirement was given as to the depth of indentation or the deformation allowed, the decision in this regard having apparently been left to the discretion of the inspecting officer. All helmets, however, were to bear the initial of the manufacturer and the heat number of the steel.........

You can read the full and very informative book here: https://archive.org/stream/helmetsbodyarmor00dean#page/n5/mode/2up

So, just what are these heat numbers and how do they work? Wikipedia has the following entry under Heat Numbers:

A heat number is an identification number that is stamped on a material plate after it is removed from the ladle and rolled at a steel mill.

Industry quality standards require materials to be tested at the manufacturer and the results of these tests be submitted through a report, also called a Mill Sheet, Mill Certificate or Mill Test Certificate (MTC). The only way to trace a steel plate back to its Mill Sheet is the Heat Number. A heat number is similar to a lot number, which is used to identify production runs of any other product for quality control purposes.

The same article also carries a photograph of a modern day heat number in situ on a steel plate - a long and fairly complex string of information which clearly means something to those inside the industry, but as far as I can tell, this number will be imprinted onto the initial rolling of the sheet of steel concerned. If that sheet of steel is then used to stamp out (in this particular case) thousands of helmet shells, I'm still intrigued as to how the heat mark would outwork itself onto each and every helmet coming out of that massive sheet of steel, and would appreciate anyone in the know offering a greater insight into this interesting topic, if they are able?

David

[Lancashire Fusilier]

David,

What a superb book, packed with great information and photographs, and a completely free download ! A must for everyone.

Thanks for sharing.

Regards,

LF

[GRANVILLE]

Actually, credit for highlighting this book goes to Terryb95 who on the 10th Dec mentioned it in his posting: http://1914-1918.invisionzone.com/forums/index.php?showtopic=203618 however, I have only just got round to raising this subject based on what I came across in the book. I'm keen to try and get to the bottom of whether or not a heat number can also be viewed as you might a batch number i.e. the lower the number, the earlier the event etc.

David

[MikB]

... I'm still intrigued as to how the heat mark would outwork itself onto each and every helmet coming out of that massive sheet of steel, and would appreciate anyone in the know offering a greater insight into this interesting topic, if they are able?

David

The helmet bowl and rim would be formed in a succession of press operations, probably with intermediate annealing stages to restore ductility to the steel between them, especially as the bowl was drawn deeper. It's logical to guess that a compartment was positioned in the die that final-formed the rim, where interchangeable letter and number punches were mounted to strike the characters. Part of the interaction between Inspection, Engineering and Production Control in the factory would be ensure that the punches were correctly changed when the plate from one heat number ran out before starting the next.

Regards,

MikB

[GRANVILLE]

MikB. Thanks for helping this simple soul try and get his head around the subject. Concerning the stamping process I think you will find each helmet was stamped in a single action out of a pre-cut flat of steel. Although this film is circa 1941, I feel sure the process was much the same during WW1: http://www.britishpathe.com/video/tin-hats-for-all/query/pressing+helmets

I'd still like to understand if, for example, 'heat number 32' telling us it was produced prior to 'heat number 38' and if so, could this be interpreted as one would a batch number in which the lower number was produced prior to the higher number. I think this an important subject to understand because there is a very real temptation to suggest that the lower numbered helmets must be the earlier one - and on the face of it, it makes sense, but on the other hand, if this a wrong principle to apply, it ought to be put to bed.

David

[bu6512]

I'd still like to understand if, for example, 'heat number 32' telling us it was produced prior to 'heat number 38' and if so, could this be interpreted as one would a batch number in which the lower number was produced prior to the higher number. I think this an important subject to understand because there is a very real temptation to suggest that the lower numbered helmets must be the earlier one - and on the face of it, it makes sense, but on the other hand, if this a wrong principle to apply, it ought to be put to bed.

David

I personally think the lower the number the earlier the helmet, however I have a Hadfields H/S 36 magnetic Brodie so did the numbering start again when Hadfields changed their stamp from H/S to HS? also the relationship between FS ans FKS? So I do believe the lower the number the earlier the helmet but I also think its not a definitive answer.

David, did you say in an earlier thread you have an HS 28? Just wondering if its a H/S or HS and if it's magnectic?

Mark

[markus]

David.

Thanks for the link to 'Helmets & Bodyarmour', much appreciated, superb stuff !

All the best.

Mark.

[scottmarchand]

Been well discussed previously - have look here: http://1914-1918.invisionzone.com/forums/index.php?showtopic=167328&hl=helmets

[GRANVILLE]

I agree, it has, in a thread largely driven by myself on account of a general interest in the development of the helmet in particular and the most authorative which came out of it was from Joe Sweeney who said:

The number on the helmet is a heat number and not a batch number.

The heat number denotes the furnace burning (that is the time the furnace was on to the time it was off in a single occurance--many batches could have come out of a single heat) that produced the metal for Quality control reasons.

Of course the smaller the number the earlier the heat, if the same furnace. However, since the metal manufacturer and helmet manufacturer were not necessarily the same--earlier heat numbers could have come out on later produced helmets.

Joe Sweeney

I asked where this information was coming from and don't recall ever getting an answer which was why my coming across the above mentioned publication of 1920 was fairly significant from my own point of view - the only contemporary source I've yet seen in which heat numbering is mentioned. Joe states the earlier the number, the earlier the heat, but with a caution. I'd just like to understand a little more about what a heat number is actually telling. Is HS 32 stating its made from steel of the 32nd furnace firing by HS (of presumably 1915) and if so, as has been touched on, this 32nd firing will have been earlier than the 37th. I think it's fine to refer to the numbers as heat numbers, but fully understanding what they mean still remains clouded to me personally and I imagine I'm not alone in this.

David

[GRANVILLE]

David, did you say in an earlier thread you have an HS 28? Just wondering if its a H/S or HS and if it's magnectic?

Mark

Mark mine is HS 28. Not at all sure what the difference to H/S 28 would be? It can be viewed here in post 158: http://1914-1918.invisionzone.com/forums/index.php?showtopic=171874&page=7 I don't know if its magnetic and can't try it as it in a museum with the rest of my kit.

David

[Joe Sweeney]

David,

Modern heat numbers tend to be much more understandable. Other than the initial denoting which concern manufactured the metal I'm not 100% sure what each number denotes? I think its just a sequential number denoting the furnace firing.

Joe Sweeney

[GRANVILLE]

David,

Modern heat numbers tend to be much more understandable. Other than the initial denoting which concern manufactured the metal I'm not 100% sure what each number denotes? I think its just a sequential number denoting the furnace firing.

Joe Sweeney

Joe. Appreciated. I rather think this sums the subject up pretty well. Now; with the benefit of a contemporary reference (Helmets and Body Armor in Modern Warfare) it is now quite apparent these rim stamps are, as you have previously said, heat numbers rather than batch numbers, which I admit I have tried to argue in the past, and that whilst not fully understood, they are in some way sequential, as you say, which will still mean that the earlier the number, the earlier the steel was produced from which the shell was ultimately made.

David

[aef1917]

From specifications dated 18/11/1915

From specifications dated 14/9/1916

[Joe Sweeney]

Aef1917,

Thanks-Interesting

Joe Sweeney

[Michael Haselgrove]

Granville,

Just when you get used to calling them heat numbers along comes aef1917 with a specification from 14/9/16 that refers to them as cast numbers. All very confusing. I am unsure that we will ever fully understand this subject. I am still not convinced that the numbers were used sequentially and we don't know how many helmets were produced from one heat/ batch/cast.

For instance, I have two raw edge helmets, both with the early liner and two piece chinstrap. I would say that they were manufactured at about the same time. However, one is marked FS 13 and the other FS 122.

Anyway, a very interesting subject and worthy of further research.

Regards,

Michael.

[GRANVILLE]

Granville,

Just when you get used to calling them heat numbers along comes aef1917 with a specification from 14/9/16 that refers to them as cast numbers. All very confusing. I am unsure that we will ever fully understand this subject. I am still not convinced that the numbers were used sequentially and we don't know how many helmets were produced from one heat/ batch/cast.

For instance, I have two raw edge helmets, both with the early liner and two piece chinstrap. I would say that they were manufactured at about the same time. However, one is marked FS 13 and the other FS 122.

Anyway, a very interesting subject and worthy of further research.

Regards,

Michael.

Hi Michael.

I've been holding off commenting on this revelation as I didn't want to come across as someone intent on stirring a pot again, but it has to be said, just when you think you've grasped a subject, something comes along and shakes it up a bit.

The quoted specifications by aef1917 are a great find and in fact it would be good to know more about the publication they appear in, - is there scope to get a copy of the work, I wonder? As you observe, you can now take your pick of descriptive between Heat/Batch and/or Cast Code, although I suspect there is a case to argue that Heat & Cast are effectively one and the same thing?

Personally, I do still subscribe to the numbers being sequential in that regardless of what the codes actually refer to, I just cannot see a reason why the same manufacturer would turn out one 'Batch' (for arguments sake) and then weeks later turn out another but with a lower sequential number than the former.

This would still be my view concerning your own FS 13 & FS 122. Both clearly from the same maker, but why would FS 122 be so numbered if it was made several weeks/months before FS 13? Please note I am only theorizing. I'm not sure the type of liner/chinstrap will have much bearing as the shell markings will relate to shell and the steel it is made of rather than the liner, so an early shell could easily have been refurbished several times during its time in active service and may well have been refitted with an earlier type of liner than the shells apparent date of manufacture, if an earlier pattern just happened to be the pattern that was readily available at the time of the refurbishment - needs must and all that.

Again; all just theory.

David

[Andrew Upton]

This would still be my view concerning your own FS 13 & FS 122. Both clearly from the same maker, but why would FS 122 be so numbered if it was made several weeks/months before FS 13?

I'm wondering if it's as simple as the fact that whilst the steel would be numbered sequentially as it was produced, it would not necessarily follow that it would be used up in the exact same order when it was being stamped into a helmet. For example, if the sheet steel was being stacked as it was produced the higher numbers might be on top, and then could be stamped in reverse order (later/larger numbers coming off first), thus a later production helmet could easily have a lower number than one made earlier.

[GRANVILLE]

Andrew,

I wish I could answer that one.

David

[Michael Haselgrove]

Hello David,

Thanks for your reply. As far as terminology is concerned, my own view is that heat/batch/cast are interchangeable as I think I mentioned in another thread.

Sorry if I gave the impression that my helmet FS 122 might have been made before the one marked FS 13. I am prepared to accept that FS 122 was made later, but not by many months.

I suppose the only way to make progress with this issue is to carry out a survey. I think that has already been attempted without conclusive results. A further attempt will probably only lead to "debate" as to whether a given helmet has a replaced liner/had lost the rim, etc. However, I am very happy to take part if you feel like another try?

Regards,

Michael.

[Andrew Upton]

I wish I could answer that one.

Similar manufacture behaviour has been noted with Vickers gun components that were serial numbered consecutively as made, but stored in bins until required, with newer components being added on top and usually being more readily to hand, thereby getting used first.

[aef1917]

Anyway, a very interesting subject and worthy of further research.

What's Marcus Cotton up to these days?

The quoted specifications by aef1917 are a great find and in fact it would be good to know more about the publication they appear in, - is there scope to get a copy of the work, I wonder?

They are not in a publication as such. When the US began looking into steel helmets in 1916, they acquired examples of the Adrian and Brodie. While the Ordnance Department had to rely on accounts in the popular press to glean the details of the Adrian's manufacture, the British were quite keen to help out, sending no fewer than four sets of specifications for the Brodie. There is at least one original blueprint of the Type D shell as well, but I was unable to get a copy of it on my last research trip.

Anyone interested in copies can PM me with their email address.

[Jerry B]

I have two rimless helmets, one H/S13 and the other HS 252.

 

I assume H/S is earlier than HS and 13 is earlier than 252 and that possibly the sequence of numbers restarted with the change from H/S to HS. Has anyone seen low numbers with the HS mark as possibly the number sequence did not change merely the naming.