DER X4 PC series

DER X4 PC series
  • About safety window
  • Introduction
  • Spec.
  • Insurance
  • Certification
  • Test video
  • The origin of the safety window for machine tools

     High speed machining with advanced technology causes an increasing risk of the ejection of the internal parts by accidents. Therefore, the German Machine Tool Builders' Association (VDW) began a series of researches regarding the design and dimensioning of guards in machine tools since 1997. The findings also lead to safety standards for machine tools defined by the European Union.

     According to the statistics of accident, chuck in the lathe caused the most much casualties since it is the heaviest part (over 2.5kg) in the list of components might ejected. For milling machine, milling cutter is the most often ejected components therefore it less than 0.1kg usually.

    However it could not take it lightly, the impact energy of components ejected would be much more than its actual weight. To prevent accident happen the safety window of machine tools has to be assessed by exactly and professionally.

  • Ageing of PC vision window 

    Ageing of PC window
    The polycarbonate had already been proved that it is the most suitable material for safety windows for machine tools due to the high impact resistance. But the researches also showed that single layer of PC used in the machine window will be ageing under the influence of the metalworking fluids, cooling lubricants and cleaning solvent etc. in the machining process. The situation might be a potential risk for machine tools operators, since the safety window used to be main protection for operators from ejected objects.

    Impact resistance of safety window made by polycarbonate would reduce to 60% after using 2 years and even has a significant reduction about 80% after using for approximately 7 years under working environment. Therefore the operators will be at high risk of injury caused by internals ejected with high impact energy from the working zone. The German Machine Tool Bullders’ Association (VDW) also takes the PC vision window as consumptive materials and should renew regularly to keep operators safe. 

  • Safety regulations defined by EU

    Evolution of safety window
     The machine tool is flourish nowaday to make the process quicker the operating speed had been elevate a lot. However when unexpected accidents happen either cutting debris, tool breakage, loose jaws or working pieces pop, higher speeds mean higher impact energy of the ejected parts will make and put the machine operator exposed to extremely dangerous working conditions even cause life-threatening.

    Therefore, the EU has already defined the relevant safety regulations in machine tools to make sure that machine operators were properly protected and declare that all the products in the EU market have to conform to the inspection standard of this safety regulation.

  • Upgrade your machine window now!  

    replace steel grill
    Derstrong can provide high quality safety window which comply with EN ISO 23125 and EN ISO 16090-1 (EN 12417) by integrating both advantages of glass and polycarbonate to achieve irreplaceable safety window for machine tools.

    We have confidence to create added value and enhance the visibility of your machine tools, and then become the noticeable spotlight in the industry. Derstrong Enterprise Co., Ltd. aim to provide the total solution rather than sell the safety window only. (the same as 1.about competitive advantage)

PC series is designed to increase scratch resistance for the panel of safety window 

  • Acquired high toughness and impact resistance property
  • Polycarbonate sheet could increase abrasion-resistance with additional coating and UV protection with additives or special surface treatment to strengthen the panel.
  • Polycarbonate can undergo large plastic deformations without cracking or breaking to absorb the impact energy to prevent operators form injury.

Key features 

  • Single or double layers of polycarbonate sheet.
  • Excellent impact resistance.
  • PC sheet with hard-coating could higher abrasive resistance and postpone material aging lower.
  • Shatterproof and anti-spalling design
  • Safety shield for the operator during processing
  • Controlling the risk form ejected parts


  • Prevent the electrostatic interference with an anti-static coating.
  • Clear vision without iron grid
  • Customization and curving type are both available
  • Complete traceability system each product has own ID number.
  • Durable, high quality and reliability.
safety window PC


  •  Small and large CNC lathe, milling machine
  •  Grinding machine and machining centers
  •  Other metalworking equipment

CE conformity 

  • Verified by TÜV Rheinland
  • EN ISO 23125 & EN ISO 16090-1(EN 12417 before)
  • Safenet EC Examination Certificate

DER X4 PC series Impact energy and EN ISO 23125 & EN 12415 Resistance classes table
(For turning machines and small lathe etc…)

Product Types Thickness (mm) Tolerance±5% Resistance Class EN ISO 23125
(EN 12415)
Work holding device diameter (mm) Peripheral speed (m/sec) Projectile dimensions (mm) Projectile mass (kg) Impact speed (m/sec) Impact Energy (joule)
DER PC 3.0 3.0 A1   130 25 30X19 0.625 34.25 366.6
DER PC 4.5 4.5 A2   130 40 30X19 0.625 52.08 847.6
DER PC 12.0 12.0 A3   130 63 30X19 0.625 83.33 2170
DER PC 6.0 6.0 B1 130 260 40 40x25 1.25 51.02 1628.2
DER PC 8.0 8.0 B2 130 260 50 40x25 1.25 64.1 2570.1
DER PC 12.0 12.0 B3 130 260 63 40X25 1.25 83.33 4343.6
DER PC 8.0 8.0 C1 260 500 40 50x30 2.5 51.02 3253.8
DER PC 9.5 9.5 C1 260 500 40 50x30 2.5 52.08 3390.4
DER PC 12.0 12.0 C2 260 500 50 50x30 2.5 64.1 5136
DER PC 15.0 15.0 C3 260 500 63 50x30 2.5 80.65 8130.5

DER X4 PC series Impact energy and EN ISO 16090-1 (EN 12417) Resistance classes table
(For turning machines and machining centers)

Product types Thickness (mm) Tolerance±5% Impact speed (m/sec) Impact Energy (Joule) Projectile dimension (mm) Projectile mass (kg)
DER PC 3.0 3.0 78.1 305    20x41                     0.1Kg                
DER PC 4.5 4.5 89.3 398.7
DER PC 6.0 6.0 102 520.2
DER PC 8.0 8.0 125 781.3
DER PC 9.5 9.5 128.2 821.8
DER PC 12.0 12.0 156.3 1221.5
DER PC 12.6 12.6 156.3 1221.5
DER PC 14.0 14.0 156.3 1221.5
DER PC 15.0 15.0 172.4 1486.1
DER PC 16.6 16.6 172.4 1486.1
DER PC 24.0 24.0 193 1862
DER PC 24.6 24.6 200 2000

DER X4 PC series Impact energy and EN ISO 23125 & EN 12478 Resistance classes table
(For turning machines and centers, such as large lathe)

Product types Thickness (mm) Tolerance ±5% Impact speed m/sec Impact energy (Joule) Projectile dimension ( mm ) Projectile mass(kg)
DER PC 8.0 8.0 50 3125 50x30          2.5     
DER PC 9.5 9.5 55.56 3858.6
DER PC 12.0 12.0 64.1 5136
DER PC 15.0 15.0 80.65 8130.5
DER PC 32.0 32.0 119 17701.3
DER PC 8.0 8.0 50 3125

All series products conformity with CE certification subject to Directive 2006/42/EC 

  •  EN ISO 23125 for CNC Lathe certificate
  •  EN ISO 16090-1 for machining center ( EN 12417 before)
  •  Verified by TÜV Rheinland


Impact resistance test video

  • All series of safety windows are CE certificated.
  • Customizable safety window for machine tool.
  • All series products passed impact test.