1. Bowers Metrology
Special ProductsSpecial Products

2. Application List
3 Point Groove
2 point Groove
3 point spherical
2 point spherical
Internal threads
External Threads
Internal Splines
External Splines
Large Internal
Diameters
Deep Hole systems
Gun Barrel Bore
gauge
Small Blind Bore
Depth stops
Brake caliper
Internal Ball race
Internal Ball-screw
Taper Gauges
OEM
Special Forms
2 point slot width
AOA

3. 3 Point Groove
• Available from 6-300mm diameter
• Interchangeable with standard heads
• XTA, XTD, XTH, Superbore.
• Special forms, Radius, Ball contacts.
• Depth stops available for quick location.
• Annular grooves possible.

4. 3 point head for Baker Hughes

5. Groove diameter and depth inspection again Baker Hughes,
Belfast.

6. Dimension from end of bore to front of groove. This head
measures a distance not a diameter. The anvils are used to set
the datum position. Hughes Tool, Texas.

7. 3 point groove + large range. Reed Tool,
Texas

8. Pins extended for Annular groove. Also useful if a boss
interrupts measurement of a blind bore

9. 3 point head to measure Brake caliper. Anvil
head for Delphi China.

10. Close-up showing measuring
position

11. Thread head
• Use with all Digital systems
• Metric, UN, Buttress, Acme, Trapezoidal, Ball screw and
non-standard forms available.
• LH and RH
• Effective (Functional), Pitch & Major measurement
• Calibrate from thread rings (Plain ring for Major
Diameter)
• Rings marked with actual PD
• Very fast measurement of threads

12. 2 point Thread head. Supplied
into Bowers France.

13. 3 point thread head for Pitch
diameter.
• Note single thread form!Note single
thread form
for pitch
diameter
Note single
thread form
for pitch
diameter

14. Small 2 point thread head below
M10 / 3/8” with slot width head.

15. Ballscrew thread heads. Originally for Thomson IBL but now
to TRW, ZF Steering

16. 3 point / 2 point spherical
• Use with any digital system
• 2 point available from 3mm, 3 point
available from 6mm
• Ease of use for operator
• 2 point supplied spherical as standard above
6mm
• Allows for misalignment in bore

17. • Tool steel anvils with XT / BS. Superbore
carbide above 50mm
• Very low wear
• Always use for deep hole measurement

18. 3 point spherical for Electro-
impact used on A380

19. http://www.electroimpact.com/
• All Electroimpact heads are used on the
large machines drilling the A380 wings.
The heads are used for automated
inspection of every hole machined. The
head shown is manufactured with a tapered
cover plate this allows for mis-alignment of
head when first entering the bore. Supplied
in the region of 100 off via Fowler in the
US.

20. Close-up spherical anvil on 35-
50mm head

21. Internal Splines
• Use with any digital system.
• 2 point between pin most popular. Can also
supply with carbide ball contact. 3 point
also available with irregular spacing if
necessary.
• Heads for Major and Minor dia. available.
• Calibrate from standard plain rings.
• NTN (Renault supplier) largest customer
with over £100K

22. Order for NTN 2 point between ball dimension

23. 2 point spline head with pins on
BS. This head was pre unit
construction of the anvils

24. Deep hole Pneumatic system
• Maximum depth we can measure 15metres above
50mm diameter (Pneumatic system)
• Accuracy +/-0.005mm at 15 metres depth.
• 6 Bar air pressure required either from compressor
or factory air supply.
• Usually 3 point but can supply 2 point, all with
spherical anvils
• Maximum diameter so far supplied 400mm.
• Simple operation.
• All heads should have guide sleeve
• Not effected by temperature fluctuations
• Calibrated prior to assembly

25. Deep hole XT
• Maximum depth 2 metres above 20mm diameter
• Can supply as 3 point or 2 point spherical
• Use 500mm long extensions 20mm+
• Use 1000mm extensions 35mm +
• Can be effected by temperature.
• Require same depth in front of the bore being
measured as is calibrated assembled.
• Not for use for high precision inspection
• Try to use in a temperature stabilised environment.

26. Deep Hole Pneumatic
• Photograph to follow

27. Deep hole XT with 1000mm
extension

28. Large Diameter. Two of 4 special large diameter heads produced for R.J
Tubular. Largest is 18.45” - 19.45” shown with 6-8mm head in
foreground

29. Rivet Height Gauge

30. 40mm Cannon Rifle groove.
The angle on the face is to allow the form to follow the groove around
the helix. The nose piece unscrews to allow a camera to interchange for
visual inspection

31. Universal Gauge. Most popular modification is longer arms. Have
produced up to 300mm. Special width depth stops , larger ball contacts
are also popular.

32. CBG. Most popular and Longer / shorter stems. Maximum depth we
recommend is 2 meters above 50mm. RA adapters can also be supplied
for CBG with photograph to follow.

33. Special head measure tin can
internal diameter with reduced
force

34. View looking down inside the
can showing the anvils

35. Product Breakdown
58%
18%
7%
17%
3-Point
Specials
Universal
Others

36. Special Products Summary
• Standard Thread, Spherical and Groove
prices shown in price list
• Recommend obtaining quotation if range of
threads is to be measured
• Drawing to be supplied if special features
are to be checked
• Please ask if unsure of application – good
chance that solution has been previously
provided