Hydraulic valve housing

Machining requirements

• Fluctuating cast allowance situation
• Heavily interrupted cuts
• Avoid ring formation during boring and ensure safe chip removal from the housing
• Avoid macroscopic flaws on the control edges in the boring process
• Very high demands on form and position tolerance
• Constant stock removal before honing
• Take part variance and limited tool storage places in the machining concept into account

Spool bore

Spool bore

The relative movement of the spool along the control edges controls the flow direction of the fluid.

Compensator bore

Compensator bore

Despite different loads on agricultural and construction machinery, the volume flow for the lifting and lowering speed on an excavator shovel, for example, must remain constant. If a low load is present, the spring-preloaded pressure compensator releases a smaller cross section, to keep the volume flow constant. With high loads, a larger cross-section is released. The working speed of the hydraulic cylinder connected to the excavator shovel thus always remains the same.

Additional bore machining

1__Tie rod hole 2__O-ring bore 3__Oil bore 4__Thread bore 5__Port hole 6__Check valve hole

• 
  1 / 6

  Tie rod hole

  Bore for tie rod, which keep the individual valve blocks together.
• 
  2 / 6

  O-ring bore

  Countersink for O-rings for sealing the plane surfaces between
  individual modules.
• 
  3 / 6

  Oil bore

  Oil channel for distributing the oil in the part.
• 
  4 / 6

  Thread bore

  Bores for fastening attachments.
• 
  5 / 6

  Port hole

  Bore for connecting the individual consumers to the valve block.
• 
  6 / 6

  Check valve hole

  Check valves for blocking a volume flow.

• 1__Tie rod hole 1__Tie rod hole
• 2__O-ring bore 2__O-ring bore
• 3__Oil bore 3__Oil bore
• 4__Thread bore 4__Thread bore
• 5__Port hole 5__Port hole
• 6__Check valve hole 6__Check valve hole

Application solutions

1 – Small and medium series with fixed tools

Initial situation at the customer

Valve housing EN-GJS-400-15 – spool bore

• Individual orders, smaller and medium quantities
• No option for tool setting
• Short cycle times required
• High machine hourly rates
• Stable oscillating honing available
• Tool concept adapted to several part versions

Details

2 – Large series with solid and adjustable tools

3 – Small lot sizes – Reduced tool changes due to combination tools

Initial situation at the customer

Valve housing EN-GJL-300 – spool bore

• Small lot sizes
• Option for tool setting available
• Too many/frequent tool changes
• High machine hourly rates
• High effort due to single pass honing process

Details

4 – Flexible honing on the machining centre

Initial situation at the customer

Valve housing EN-GJS-400-15 – Compensator bore / honing

• Request for reduction of ancillary costs
• Existing machining centre re-tooled to TOOLTRONIC
• Honing for prototype manufacture, as well as small and medium-scale production runs
• Requirement for saving the honing process on separate machine

Details

5 – Tool management

Details

Tool solutions