Tool drawings were also required to perform critical functions related to tablet quality and tablet press operation, including
tool inspection procedures and setting limits and controls for punch and die maintenance. The tool drawings also enabled operators
to troubleshoot compression and machine problems, such as poor tablet friability, punch binding, and premature tool wear.
But most important, the long-term motive of the committee was to publish a tooling standard that governs and softly mandates
tablet press and tooling manufacturers to produce equipment in compliance with the American standard. Establishing tooling
standards helped to protect the millions of dollars invested in current tooling inventory while maintaining the integrity
of established processes and procedures for tool inspection and maintenance. The standards also provided the pharmaceutical
industry a uniform price structure useful for budgeting.
Unlike the American TSM standards, the "Euronorm" European standard tool configuration is not published or governed by an
organization or association. However, the European tool configuration has been refined and slightly modified from the original
Manesty design by European tablet press manufacturers to meet the demand of modern high speed and automated tablet presses.
So today we have two configurations of the world's most common B and D tooling designs; the TSM and the Euronorm. In the past
two decades, Europe has dominated the tablet press industry. Therefore, all tablet presses manufactured in Europe for use
in the United States must be modified from European design to meet the requirements of the TSM tool configuration. Unfortunately
for American tablet manufactures, the Euronorm tool configuration is superior in design and function over the American TSM
type. To obtain the peak performance of high-speed tablet presses, serious consideration should be given to modify the original
TSM tool configuration to better match that of the Euronorm configuration for which the modern presses have been engineered.
Where do we go from here?
Modifications to the TSM tool configuration are called tooling options and listed in the current TSM Manual. The US is the
only country in the world using the original Stokes design, so products being transferred to or from the US may react differently
to compression settings and may not be consistent with the original manufacturing site. The two tool configurations are so
close to each other that it may be time to consider a world tooling standard. Such a standard would allow consistent tooling
and press performance regardless of manufacturing location and interchangeability of tooling between countries. It also would
provide a benefit to the tablet press manufacturer who would then be able to produce presses using only one common tool configuration.
Here is a list of the differences between the TSM and Euronorm tool configurations:
- The TSM punch head configuration has an angled top profile compared with the Euronorm configuration, which uses a domed type
head profile. The domed head profile accepts the pressure of the compression roller for tablet compression and reduces the
shock and bounce that commonly occurs with the TSM angled profile. Tablet press cams designed for TSM tooling can use the
optional domed head design without further modifications to the tablet press or cams and should be considered a standard for
all high speed presses.
- The TSM punch inside head angle for B type punches is 37° compared with the Euronorm, which is 30°. The difference between
the head angles provides no benefit for either configuration. The inside head angle for the D type configuration however is
the same 30° angle for both the TSM and Euronorm type.
- The overall head thickness is greater in both the B and D configurations for the TSM than for the Euronorm type. Manesty's
original theory was that reducing the head thickness would reduce the weight. A lighter punch requires less energy to move
vertically through the various compression cycles.
- The overall punch length of the TSM tool is 0.010 inches shorter than the Euronorm and provides no benefit to either configuration.
The major difference between the two competing tool configurations is the angled head profile of TSM versus the domed head
profile of the Euronorm, with the domed head profile being the configuration of choice by the modern, high speed tablet press
manufacturers. I see no advantage in maintaining two tooling standards for reasons that cannot truly be justified. Establishing
a single punch configuration only makes good sense and will provide overall consistency and efficiency to the pharmaceutical
Dale Natoli is vice-president of Natoli Engineering, email@example.com