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This ducument (M.Dv.147 No. 27) was provided to this Archive by Peter Lienau. It was translated from the original German by Ulrich H. Rudofsky and transcribed into the HTML format seen here by José M. Rico. Special assistance editing this document came from George H. Elder, Greg Locock, and Peter K. Notes by the editors are placed within the text in square brackets - [...] - followed by their initials.

Updated: 12 March 2002

Proof No. 24

State Secret!

Observe Secrecy Obligation.

General Construction Regulations 1 No. 27

Delivery Regulations for Armor Materials

Berlin 1938

New Edition [Printing] 1939

Naval Forces High Command

Naval Administrative Directive No. 147

Table of Contents.

1. Supply Objectives

    A. Homogenous material, non-tempered
    B. Material with tempered surface
2. Delivery documents
    a. submitted by the Naval High Command
    b. submitted by the shipyard
3. Delivery order and delivery deadlines

4. Bid classification

    a. homogeneous material
    b. single-sided tempered material
5. Supervision of Control

6. Technical requirements

    A. General data
    B. Technical testing
          a. raw materials
          b. measurement and weight tolerances
                1. armor plating material (non-tempered, homogeneous)
                Table for permitted thickness deviations
                2. armor plating material (single-sided tempered)
          c. quality control
          d. strength testing
          e. chemical testing
    C. Firing test
          1. non-tempered armor material
                a. selection of metal plates for firing test
                b. artillery testing procedures
          2. single-sided tempered armor material
                a. selection of plates for test production
                b. selection of plates for firing test
                c. artillery test procedures
    D. Acceptance
7. Replacement deliveries

8. Costs of firing tests

9. Utilization of scrap metals

1. Objectives of the delivery.

The following types of armor materials shall be considered for delivery:

A. Homogeneous material, non-tempered

1. Ww K, soft [ductile] quality of the Fried. Krupp, A.G., Essen
2. Wh K, a harder quality of the Fried. Krupp, A.G., Essen
3. Wh R, a harder quality of Ruhrstahl, A.G., Essen
4. Wh D, hard quality of Dortmund-Hoerder Ironworks Union, Dortmund
5. Wsh K, hard quality of the Fried. Krupp, A.G., Essen

B. Material with tempered surface.

1. KCn/A, “cemented” processed steel, single-side tempered, new type of the Fried. Krupp, A.G., Essen
2. KVC, “cemented” short process, single side tempered steel of the Fried. Krupp, A.G., Essen

These designations apply to rolled (sheet) material. Foundry pieces to be delivered that are of similar Wh composition.

These materials can only be requisitioned from mills that have been approved for this supplier’s list.

2. Supplier’s Documentation.

The following references for the production of armor steel materials have been published as follows:

a. from the Naval High Command:
the illustrations of:
{armoring procedure}
{armor splicing}
{list of plates}
for rolling mills, construction yards and convening boards of Navy Shipyards.

b. from the construction yard:
Requisitions (bid listings) to the rolling mill.

The measurements, shapes, and quality of the plates must be clearly evident in the requisitions.

If the documents [provided to manufacturers] are insufficient [in detail] for the production of armor, the rolling mill shall receive upon application to the shipbuilder’s yard [for more specifications] further [sets of] scaled drawings, templates, or models [mock-ups] which are to be clearly labeled and identified with the construction number of the ship.

In the case of non-tempered, simple, plain, and unformed plates, the requisitions shall be in the hands of the rolling mill 10 weeks before the required start [date] of delivery.

This interval is greater for requisitions of tempered plates that require additional mill work or that need to be formed (bent). This needs to be negotiated case-by-case; similarly, [this case-by-case procedure is required for] the time [needed] for anticipated requests for [mould loft] patterns and models.

The Naval High Command strongly obliges construction shipyards to send rolling mills further required documents for the production of armor plating at least 6 months before the start of the delivery of the applicable bid.

3. Requisition Placement and Delivery Deadline

During the signing of contract negotiations with the rolling mill, care must be taken to forcefully inform the rolling mill that in case of delivery of faulty materials, replacements must be provided free-of-charge.

The delivery deadlines for armor materiel will be negotiated before requisitioning, on a case-by-case basis between the rolling mill and the Naval High Command, i.e., the construction yard.

The rolling mill shall fully agree to accommodate the requisitioner’s wishes as to time and sequence of deliveries.

When negotiations are conducted by the yard, a copy of the delivery contract must be submitted to the Naval High Command.

4. Management of Bids

The distribution of requisitions to the rolling mill for plates, i.e., supply materiel, are based on a bidding contract system.

Each bid is to be divided into two halves. Each bid shall obtain to sheet metal and plates of only a single quality, e.g., KC n/A or Ww, respectively, Wh. The butt plates [scraph or fish plates] for the metal sheets [what are Laschen in this context? UR] shall be part of the same lot, even if they are of a different quality [specification].

When possible, each bid shall include:

    a) for homogeneous non-hardened material (W-material) at least 20, but not more than 50 finished tempered, milled raw sheets with a maximum weight of 300 t. The latter weight can be exceeded, if the number of plates is met.
    b) for single-sided hardened materiel (K-materiel): up to approximately 25 tempered and milled raw sheets of metal with a maximum weight of 600 t. The prescribed maximum weight cannot be exceeded.
From the remainders of more than 25 metal sheets or more than 150 t of W material, i.e., 300 t of K material, a consolation bid is to be issued. The distribution of half bid vouchers in this case is suspended. A lesser remainder is to be distributed among the lots that are milled at that time.

The bids will be distributed by the construction yard with consideration [being made] regarding building requirements.

The construction yard shall submit each time to the Naval High Command two bidding lists. This bidding list shall contain the thickness, designation, type of material, and weight of each metal sheet. The designated use of the metal sheets must be clearly self-evident [by a notation of necessary].

The designated use of the sheet metal and the ship’s type [for which they are requested] shall not be divulged by the bidding and order lists or by correspondence with the rolling mill. Therefore, the individual groups of sheet metal are to be given innocuous designations as determined by the yard’s discretion [choice]. The ship’s name is to be replaced by the builder’s number.

5. Quality Control Supervision

The Naval High Command and its deputy, the Office of Naval Ship Yards, has the right, at any time, for [on-site] inspections by its officials of the production and thermal treatment of sheet metals during their individual processing.

6. Technical Requirements

A. General Considerations

The armor material shall possess the required quality that has been specified for the plates, respectively, in the order list.

Several types of material shall have additional quality designations [shown] on the armor plates which may not have been necessary in the past.

Non-tempered plates (homogeneous W material) are, in general, to be delivered rolled flat (+/- 15 mm deviation) or adjusted to +/- 5mm deviation according to the list, of plates that are milled edges. The yard may wish to have the plates delivered adjusted to +/- 3 mm deviation. These plates must be specially marked in the bid lists.

The tempered plates (K material) are to have finished edges and the designated places are to be milled according to drawings, patterns or models (see General Construction Orders II, No. 10 {Allgemeine Baubestimmungen A. B. B.}).

The butt plates [Laschen= butt or scarph plates or straps? UR] shall be made from Ww material , [while] the armor plating screws and bolts [shall be made] from steel according to Regulations of Materials for the German Navy, No. 15, Edition 1915.

Barbettes, command towers with roofs [ceilings? UR] and floors, and command tunnels are to be delivered finished, with attached butt plates and connector screws as well as the required threaded holes in the armor plates.

Every rolled plate from 60 mm thickness upward will be assigned a factory serial number by the rolling mill. All sheet metals of a lesser thickness will be stamped with the melting point?? number [smelter or foundry?] number UR

B. Technical Testing Procedure

Sheet metals and plates shall be subjected to a [battery of] technical tests according to the following regulations. [Some] precise measurements and tests are permitted to be conducted after the [ballistic] firing [proving ground] acceptance tests on a specific plate [have been completed] [Abnahmeprüfung = acceptance test? UR]. However, the [mechanical] tests must precede the artillery tests.

Test samples [from lots] can be removed only after the sheet metal selection process for the firing test is concluded (compare with C). After submission, further heat treatment of the sheet metal and plates is no longer allowed. The technical testing of the armor material shall be initiated by the stationed [resident] naval supervising official at the rolling mill and [he] will apply to the Naval High Command for the dispatch of a sampling official for testing according to 6. B. d). [Stationing government supervisors within production facilities is a far different process than was used in the US and Great Britain, GHE]

a. Raw Materials

                        Tensile strength test (rod diameter 12 mm x 60 mm length) notch-impact test

Raw material type Flow limit
Stress limit
Expansion [stretch] limit
L= ð d
Compression [coefficient]
Notching resistance (half value of the Charpy Test 160x30x15 mm round notch at 4 mm diameter)(see page 6)mkg/cm
K C n/A The testing of K Cn/A is not required at the time of testing
Ww Min. 48 65-75 Min. 22 Min. 65 Min. 28
Wh Min. 56 80-90*) Min. 18 Min. 60 Min. 22 [not legible]
Below 20 mm 65 90-100 Min. 14 52 Min. 18
20-30 mm 65 90-100 Min. 18 55 Min. 20

[footnote is only partially readable. It is covered by an overlay strip: something about achieving allowable values ………….(see page 6). UR]

b. Measurement and Weight Limits.

1. Armor plating (non-tempered homogeneous material Ww, Wh, and Wsh). As far as no special contracts are made:

Length for sheet metal under 20 mm thickness

for sheet metal above 20 mm thickness

-0 mm
+25 mm
+30 mm

Width for sheet metal under 20 mm thickness

for sheet metal above 20 mm thickness

-0 mm
+10 mm
+20 mm

Deviations from the calculated weight within a lot: none above, under 5%.

It is advised that the calculated weight standard be attained from [a volumetric function based on the dimensions and] the prescribed thickness [of the plates]. High or under weights are to be balanced within the lot.

Table for the admissible deviations of thickness:

Sheet metal width taken at right angle to the roller direction in mm

Allowable short measurement in mm at the requested thickness in mm

1001 to 1500
1501 to 2000
2001 to 2500
2501 to 3000
3001 to 3500
3501 to 4000
4001 and above

It is permissible to conduct the exact measurement and weighing after the firing test.

2. Armor plating (single-sided tempered material KC and KVC).

Length and width measurement are to be exactly adhered to when feasible.

For thickness, an overestimate of +2 to +3 mm is allowed.

A measurement [below the required thickness] shall be avoided; it shall maximally measure 5 (five) mm. In regard to deviations when the form [of the plate] requires it, the rolling mill ought to be given sufficient latitude. In case difficulties arise, the Naval High Command shall be included in the resolution of the problem.

The stacks of side armor plates are to be matched, so that the center portion of the plates can be laid flush and so that the apparent deviations can be balanced between one third below and two thirds above. The stacks shall not, if at all possible, have gaps. Toward the outside, a 1 mm [gap] is allowed, toward the inside, there can be a maximum airspace of 4 mm.

Deviations from the Calculated Weight.

Exceeding the weight limitations shall be avoided when possible. It is advised to stay within the weight calculated by the prescribed thickness. Excess and low weights are to be absorbed within a single bid. The low weight cannot amount to more than 5% of the [total] weight of the plates [within a lot].

c. Quality Control


The surfaces must be virtually smooth and flat, devoid of roller blemishes (bulges, fissures, scales). Pits are only permissible if the required minimal thickness is not exceeded [by their presence].

If the Naval High Command deems it necessary, it may obtain a Baumann imprint of 100 mm from a location at the head end of the upper back edge of every mechanically tested plate. Should this imprint show unusually strong segregation [delamination or sudden grain-structure shift], an additional imprint will be taken along the sides in 300 mm intervals.

A copy of the test proceedings and the Baumann imprints shall be presented to the Naval High Command.

d. Strength Test

1. The raw materials shall be tested at the rolling mill [on site, UR]. The samples must be in the same thermal environment as the sheets that are subjected to firing [ballistic trials].

The sheets and plates shall be cut according to the wishes of the mill; however, sufficient material must be available at the head and foot [top and bottom] for samples to be taken.

The testing rods [cores] will receive the same designation as the sheet from which the sample has been removed. They are to be removed from the material with splinter-cutting tools.

2. When accepting delivery of homogeneous material, a sample for tensile and notching tests will be taken [from both the] longitudinal and perpendicular [planes relative] to the fiber direction [orientation]. The values stated in the Table in a), are valid for samples taken in the rolling direction, namely, for a tensile-test rod of 12 mm diameter and 60 mm length. Exceeding the tensile strength is admissible for Wh, if the remaining prescribed quality control values are attained.

For the notch-resistance test, a 160 x 30 x 15 mm rod machined on all sides, is removed and notched at the middle with a 4 mm round notch (half of the Charpy Test). For sheet metal under 15 mm and down to 10 mm thickness the half Charpy Test is to be used [and modified], so that there is always a rectangular cross-section remaining for penetration. (For 10 mm sheet metal, e.g., the round notch is drilled into the 30 mm rod perpendicular to the surface of the 10 mm edge.)

No notching tests are performed at a thickness below 10 mm.

The test rods [core samples] are not to be removed until after the sheets selected for firing trials have met [all] proposed requirements (refer to 6. C. 1.) .

The acceptance official will prepare a standard Navy receipt transaction voucher listing the results of the tests, and submit it to the Naval High Command.

3. For KC- respectively, KVC-plates, a sample is to be obtained longitudinally and perpendicular to the fiber direction [orientation] for tensile and notching tests for a fifth of the plates from a lot (firing test plates inclusive), however, no more than each 100 t of plate material; [for this sample] is to be obtained from the non-tempered backside of the plate near the top edge [head. UR]. A similar test sample will be removed from the bottom edge [foot. UR] of the plate selected by the Naval High Command [official] in charge of firing tests.

Regulations listed in d. 2. are applicable to the test measurements and during the receiving transactions.

Breaking Test:

In order to evaluate the depth of tempering [depth of hardness. UR] a breaking [fracturing, impact. UR] test is to be done on each test plate of a lot (preferable at the head, but at both ends for firing test plates) and a photograph submitted to the Naval High Command.

Hardness Test:

The Brinell hardness test is to be employed for the determination of the progression of the hardening process throughout the cross-section. This means that starting from the tempered edge over the entire cross-section, although to a maximum depth of 200 mm, one [hardness test] compression each shall be made [at the following intervals]; up to 40 mm, every 5 mm; up to 80 mm, every 10 mm; and then every 20 mm [up to 200 mm]. A photograph of the results of the head-and-foot end [test samples] with their recorded intervals and hardness (Brinell) numbers must be attached to the investigative results.

e. Chemical Tests

The Naval High Command may order a chemical analysis (external to the rolling mill [analyses]), but the acceptance of the material shall not depend on it.

C. Firing Test.

1. Non-tempered armor material.

a. selection of the sheets for firing.

A lot may only be submitted for the selection of sheets for firing when the metallurgical processing is concluded.

The resident naval supervisory official at the rolling mill will select test sheets from the half lots and from the leftover remainder lots, according to 6. B. d. 2., and list them in the acceptance transaction form. The requisition number as well as the designation of the sheets in their bidding distribution shall be entered and submitted to the Naval High Command with the corresponding bid list after completion of the technical evaluation. Since the plates selected for firing trials are submitted in a flat condition, and in order to prevent double tempering, an inquiry should be made for lots that contain plates of more than 300 mm thickness to ascertain if the plates are to be used for firing trials before [their] bending.

Based on the results of technical testing, the acceptance official of the Naval High Command will determine which sheet metal and reserve sheet metal [sample] is selected for firing tests and provide instructions concerning where the firing sheets are to be sent to. The naval supervisory official will inform the shipyard regarding the selection of the firing sheets. The reserve sheet will be utilized for firing only if the artillery test had been inconclusive.

The sheet metal for firing must be completely flat, unless special cases dictate otherwise. They shall not be covered with paint or oil. If a sheet has gone athwart [windschief = off to leeward. UR] due to cutting, it can only be straightened without applying heat. Stamped [selected and approved. UR] sheets may not be heat-treated again under any circumstance. In order to secure this, the stamp is to be embossed on the sheet metal with a lead seal [bung or seal. UR] (refer to: paragraph 19, section IV, pamphlet A 1 of the Regulations of Materiel for the German Naval Forces, Edition 1915).

Hand-written in blue ink in the margins with a line to “Bleipfropfen” (lead bung):

“Für die Dauer des Krieges dürfen keine Bleipfropfen verwendet werden. Der Stempel ist unter die von der Lieferfirma………[omething may be missing here. UR ]

gem. Para. 1 a Abs. 5 einzuschlagenden Chargen-und Bezeichnungsnummer der Platte mit einzuhauen. Berichtigt .. Werft Kiel
B. No. G 70692/42 B….Ober…….” [not legible.UR]

“No lead seals are allowed to be used for the duration of the war. The stamp is to be affixed below the supplier’s firm……[ something may be missing here. UR]

according to Para 1a, section 5 concerning embossing of grading [Chargen? UR]and designation numbers. Corrected .. Shipyard Kiel, B. No. G [or H? UR] 70692/42. [signature and title? UR].

Furthermore, the sheet shall be marked only with the number, bid number, and the designation on the top edge [head side. UR] by a painted K. Manufacturer’s [serial or melt] number and grade number are also to be embossed on the plate.

b. Artillery testing

The material shall be at least satisfactory in its quality and [ballistic] firing properties in accordance with the acceptance conditions for material Ww and Wh as denoted in M Wa I a 306 as of 17.1.36.

Armor plating material of less than 10 mm overall thickness shall be recorded only by its measurement and raw material tests. It will not be subjected to firing.

2. Single-sided hardened armor material.

a. Selection of plates for [high] quality finishing

As soon as all plates of a lottery are rolled, the supply firm shall submit a list of the lot to the Naval High Command. (This presentation can be done in person). The list must contain the placement of the order, the bid number, and the description of the plate list according to cipher 2a, as well as a heading of the material’s designation and builder’s number of the ship. Furthermore, each and every plate must be registered by the shipyards [for its] location on the ship, the part number, dimensions, the calculated raw weight and the batch and plate numbers. Plates already in the cementation process are to be marked.

b. Selection of plates for firing tests

The Naval High Command selects a plate as a firing plate from the bid list and informs the supply firm and the naval supervisory official for armor material at the plant in writing of the plate number without divulging the plate’s measurements.

A reserve plate for firing shall be selected on an as-needed-basis from the remaining lot of plates only if needed.

The [selected] plate for fire testing shall be immediately prepared for firing and transported to the firing range in Meppe.

All plates for firing tests will be submitted with a flat surface. If a plate is fired at in a bent condition, this shall be brought to the immediate attention of the supplier.

The firing plates shall be stamped, inscribed, and handled similarly to the sheet metal plates made for homogeneous armor materials.

The Naval Supervisory Official for Armor Materials shall order the removal of test samples from the firing plate after the tempering, to conduct the prescribed strength tests, and to order the tensile and Brinell hardness tests. The results shall be immediately submitted to the Naval High Command (if possible, before the firing test), and the samples made available from the hardness test shall [also] be made available for further analysis.

The accepting official of the Naval High Command shall examine the [results of] tests done under 6. B. d. 3. after the completion of [each] plate.

c. Artillery Test

(this is the overlay on top of the original text, cover sheet 2)

The material shall attain the quality and firing characteristics of the average of the plates of equal thickness and similar material tested within that year. This requirement is met, if the ballistic velocity limit does not fall short of the average value of tested plates of equal thickness for that year by more than 5%.

Addendum to C.1.b and 2.c. The Naval High Command orders that the artillery tests for sheet metal [shall be performed] at the artillery range.

The requirements shall be announced to the suppliers of the sheet metal, [and] if it is necessary, before the completion of the supply contract [negotiation].

The firing results must be evaluated based on the actual thickness of the firing sheet metal. This shall be calculated from the weight and surface area of the firing sheet and the assumption of the specific gravity being 7.85, and this shall be transmitted to the Naval High Command at the time of artillery testing.

D. Acceptance

The results of the artillery testing states either “fit for acceptance” or “unfit for acceptance”, and this will be immediately transmitted to the shipyard and to the Naval High Command who shall determine the utilization of the remainder of the sheet metal [in that lot]. Firing sheet metal, i.e., plates, shall be assigned a test number.

In the event of an unfavorable outcome of the artillery test, a second sheet will be chosen for firing tests from another half of the bid list respectively, or from the consolation lot. If the rolling mill withdraws a lot based on the unsatisfactory shooting results of a sample plate, the mill has liberty to reprocess the plates of this bidding lot and present them for firing plate selection again.

The final disposal of a bid or half-bid whose firing sheets were inadequate, can be made contingent by the Naval High Command upon a further shooting on a replacement sheet of its own choosing; however, a satisfactory result of [firing on] a replacement sheet shall not be construed as a guaranty for acceptance.

The Yard Administration [branch] of the Navy, respective to the [concerned] shipyard, orders [the implementation] of the decision of continuing acceptance and transport of bid lots [deemed] fit for acceptance after the artillery test. Plates greater than 100 mm in thickness shall be transported while covered.

7. Replacement Deliveries

The Naval High Command shall approve without question the same procedure for the testing and subsequent delivery of replacement bid lots and half-lots.

8. Firing Expenses

a. Homogeneous material (Ww, Wh, and Wsh).

If the firing plate meets the shooting properties under requirements listed in 6.C.1., the shipyard will bear the costs of shipping to the shooting range, while the Navy will absorb the firing costs (costs for the use of the shooting range, the mounting of the sheet metals, and for the ammunition).

b. single-sided hardened material (KC and KVC)

If the firing plate meets the shooting properties under the requirements of 6.C.1., the Navy will bear the costs of the transport to the firing range and the firing costs (costs for use of the shooting range, the mounting of the plates and the ammunition). If the shooting test results on the first firing plate require the firing at a second plate, and if this firing leads to the acceptance of this bid lot, the Navy will absorb the shooting costs, the cost for the transport of the second plate to the shooting range, and the cost of the firing plate itself. The rolling mill shall bear the expenses of the firing, the transport, and cost of the failed firing plate. Should a third plate be taken under fire, there should be rational [considerable] discussion.

9. Scrap Metal Recovery Procedure

The armor material scrap metal in shipyards shall be stored separately and returned to the armor suppliers. Under no circumstances shall the armor scrap be passed on to a scrap dealer. The shipyard is required to secure by contract the return of the armor scrap to the source of production.


Berlin, 13 March 1935

Naval High Command

As ordered: Schulz

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